real_006 diagnosis: Q43 leak is cross-city, not cross-role

Traced w-279's path through the substrate. The leak source is Q49
(Packers in Indianapolis IN for Midway Distribution), NOT Q18 as
the initial reading suspected.

Q49 recorded w-279 with role=Packers, client=Midway Distribution,
city=Indianapolis. Q43 (Packer in Chicago IL for Midway Distribution)
ran later. roleEqual("Packer","Packers") → both normalize to
"packer" → role gate passes (correctly, by design — they ARE the
same role under plural-strip). Cosine distance between Q49's
recorded query and Q43's query is small enough to fit inside the
0.20 inject threshold because role + client + count + time-token
dominate the embedding (only the city and singular/plural noun
differ). Inject fires, w-279 surfaces at Q43's warm top-1 in
Chicago, judge correctly rates 2/5 — wrong city.

The role gate IS working. What's missing is a CITY gate. Real_002's
fix targeted cross-role bleed (Forklift → CNC). real_006 surfaced
cross-city bleed within same role + same client — a hole prior
tests structurally couldn't reach because they all sourced from
rows 0-9 where no such pair existed.

Concrete fix surface documented (1 new field, 2 gate checks, 1
regex, ~5 tests). Half a session of work, same shape as real_002.
Not implementing tonight — diagnosis only.

The 18 unit-level role-gate tests still pass, confirming the gate
is doing what it was specified to do. The bug is a missing
specification, not a broken implementation.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

STATE_OF_PLAY.md

@@ -1,9 +1,9 @@
 # STATE OF PLAY — Lakehouse-Go
 
-**Last verified:** 2026-05-02 ~05:00 CDT
-**Verified by:** **production-readiness gauntlet** — 21/21 smoke chain green in ~60s, per-component scrum across 4 bundles (no convergent findings, no real bugs), cross-runtime validator parity probe (6/6 status match, 5/6 body shape divergence captured as known gap). Disposition: `reports/cutover/gauntlet_2026-05-02/disposition.md`.
+**Last verified:** 2026-05-02 ~11:30 CDT
+**Verified by:** **production-readiness gauntlet** — 21/21 smoke chain green, per-component scrum across 4 bundles, **6 cross-runtime parity probes all green: 38/38 byte-identical assertions** (validator 6/6 after wire-format alignment, materializer 2/2 after omitempty fix, extract_json 12/12, session_log 4/4, embed 8/8 cosine, subject_audit 6/6 after the three runtime-divergence-class fixes documented at `lakehouse/STATE_OF_PLAY.md` lines 36-39). All findings surfaced by the parity probes have been actioned. Disposition: `reports/cutover/gauntlet_2026-05-02/disposition.md`. Subject-audit probe added 2026-05-03 (`262a77a`).
 
-> **Read this FIRST.** When the user says "we're working on lakehouse," default to the Go rewrite (this repo); the Rust legacy at `/home/profit/lakehouse/` is maintenance-only. If memory contradicts this file, this file wins. Update it when something is verified working — not when a phase finishes.
+> **Read this FIRST.** When the user says "we're working on lakehouse," default to the Go rewrite (this repo) but ASK if ambiguous — the Rust system at `/home/profit/lakehouse/` is also receiving real work as of 2026-05-02 (Lance backend hardening, observability parity, sidecar drop — see `lakehouse/STATE_OF_PLAY.md`). The cross-runtime decisions tracker at `docs/ARCHITECTURE_COMPARISON.md` is the single source of truth for what's open across both. If memory contradicts this file, this file wins. Update it when something is verified working — not when a phase finishes.
 
 ---
 
@@ -198,7 +198,7 @@ Verbatim verdicts at `reports/scrum/_evidence/2026-04-30/verdicts/`. Disposition
 
 ### Session frame (don't redo)
 
-- The Rust legacy is **maintenance-only** until Go reaches feature parity. Don't propose ports of components already shipped here.
+- The Rust system is **NOT maintenance-only** as of 2026-05-02 — it's receiving parity work + infrastructure (Lance gauntlet, sidecar drop, observability parity). Don't propose ports of components already shipped on the Go side, but do expect Rust commits to land in parallel for cross-runtime fabric.
 - The matrix indexer **5/5 components** are shipped. Don't propose to "build the matrix indexer" — it's done.
 - The 5-loop substrate's load-bearing gate is **PASSED**. v3 (`154a72e`) showed 6/6 paraphrase recovery via Shape B. Don't propose to "test if the playbook learns" — it does.
 - **Shape B is the playbook stance now.** When `use_playbook=true`, both `ApplyPlaybookBoost` (re-rank in place) AND `InjectPlaybookMisses` (insert recorded answers not in regular top-K) run. Don't revert to boost-only; v2 proved that path can't recover paraphrase queries.
@@ -216,6 +216,8 @@ Verbatim verdicts at `reports/scrum/_evidence/2026-04-30/verdicts/`. Disposition
 - **Langfuse Go-side client lives at `internal/langfuse/`** with best-effort fail-open posture. URL+creds from `/etc/lakehouse/langfuse.env`. Don't propose to "wire Langfuse on Go side" — it's wired; multi_coord_stress is the proof.
 - **vectord's source-of-truth is `i.vectors`, NOT the coder/hnsw graph.** The `Index` struct holds a parallel `vectors map[string][]float32` updated on every successful Add/Delete; the graph is a derived, replaceable view. `safeGraphAdd`/`safeGraphDelete` wrap the library's panic-prone ops; `rebuildGraphLocked` reads from `i.vectors` (graph-state-independent). Don't propose to "drop the side map for memory" — it's the load-bearing piece that makes Add panic-recoverable past the small-index threshold (closes the multitier_100k 277884b 96-98% fail). The prior `i.ids` set was folded into `i.vectors` keys.
 - **vectord saves are coalesced async, not synchronous.** `cmd/vectord/main.go` runs a per-index `saveTask` that single-flights through `Persistor.Save` — at most one in-flight + one pending. Add returns OK before the save completes; an Add-then-crash can lose ~1 save's worth of data, matching ADR-005's fail-open posture. Don't propose to "make saves synchronous for durability" — that re-introduces the lock-contention bottleneck (1-2.5s tail at conc=50, observed 2026-05-01) without fixing a real durability hole (in-memory state is the source of truth in flight).
+- **`X-Lakehouse-Trace-Id` header propagates Langfuse parent traces across daemon boundaries.** When validatord's `/v1/iterate` calls chatd's `/v1/chat`, it forwards the header so chatd's middleware reuses the parent trace id instead of minting a new one. Each iteration attempt also emits a child span (`iterate.attempt[N]`) carrying the prompt, raw model output, and validator verdict. Result: an iterate session with N retries shows in Langfuse as ONE trace tree, not N+1 disconnected traces. Don't propose to "wire trace-id propagation" — it's wired; the test at `internal/shared/langfuse_middleware_test.go::TestLangfuseMiddleware_HonorsTraceIDHeader` is the proof. Closes J's 2026-05-02 multi-call observability concern.
+- **Coordinator session JSONL exists at `[validatord].session_log_path`.** One row per `/v1/iterate` session, schema=`session.iterate.v1`, append-only. Captures session_id (= Langfuse trace_id), kind, model, iterations, attempts[], final_verdict, **grounded_in_roster** (the load-bearing forensic property — always true on accepted fills, false on phantom-worker artifacts that somehow slip past FillValidator). Empty path = disabled. DuckDB queries documented at `docs/SESSION_LOG.md`. Don't propose to "build offline session analysis" — it's built; the schema is locked at v1; rotate the file via logrotate when it gets large.
 
 ---
 

cmd/validatord/main.go

@@ -34,6 +34,7 @@ import (
 
 	"github.com/go-chi/chi/v5"
 
+	"git.agentview.dev/profit/golangLAKEHOUSE/internal/langfuse"
 	"git.agentview.dev/profit/golangLAKEHOUSE/internal/shared"
 	"git.agentview.dev/profit/golangLAKEHOUSE/internal/validator"
 )
@@ -73,6 +74,15 @@ func main() {
 			DefaultMaxIterations: cfg.Validatord.DefaultMaxIterations,
 			DefaultMaxTokens:     cfg.Validatord.DefaultMaxTokens,
 		},
+		// Same env loader the middleware uses — getting our own
+		// reference lets us emit child spans of the per-request trace.
+		// nil when Langfuse env isn't set; the iterate handler skips
+		// span emission gracefully in that case.
+		lf:         shared.LoadLangfuseFromEnv(),
+		sessionLog: validator.NewSessionLogger(cfg.Validatord.SessionLogPath),
+	}
+	if h.sessionLog != nil {
+		slog.Info("validatord session log", "path", cfg.Validatord.SessionLogPath)
 	}
 
 	if err := shared.Run("validatord", cfg.Validatord.Bind, h.register, cfg.Auth); err != nil {
@@ -86,6 +96,16 @@ type handlers struct {
 	chatdURL   string
 	chatClient *http.Client
 	iterCfg    validator.IterateConfig
+	// lf is the Langfuse client (nil when unconfigured — best-effort
+	// posture matching the rest of the stack). Per-attempt iteration
+	// spans get emitted via lf when set. The HTTP middleware that
+	// creates the parent trace lives in shared.Run; this client lets
+	// validatord's handler emit application-level child spans.
+	lf *langfuse.Client
+	// sessionLog appends one SessionRecord per /v1/iterate session to
+	// `coordinator_sessions.jsonl` for offline DuckDB analysis. nil
+	// when the session log is unconfigured (best-effort posture).
+	sessionLog *validator.SessionLogger
 }
 
 func (h *handlers) register(r chi.Router) {
@@ -224,6 +244,30 @@ func (h *handlers) handleIterate(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Resolve the parent trace id, in priority order:
+	//   1. req.TraceID (caller put it in the JSON body)
+	//   2. X-Lakehouse-Trace-Id header (read DIRECTLY here so the path
+	//      works even when Langfuse is off and the middleware is a
+	//      passthrough — matches Rust's iterate handler shape)
+	//   3. context value set by the langfuse middleware (when Langfuse
+	//      is configured)
+	//   4. fallback to a locally-minted time-ordered hex id
+	//
+	// Surfaced 2026-05-02 cross-runtime test: Go was minting fallback
+	// even when caller forwarded the header, because middleware
+	// passthrough mode never read it. Reading the header here closes
+	// the gap and makes Go behavior match Rust regardless of
+	// Langfuse configuration.
+	if req.TraceID == "" {
+		req.TraceID = r.Header.Get(shared.TraceIDHeader)
+	}
+	if req.TraceID == "" {
+		req.TraceID = shared.TraceIDFromCtx(r.Context())
+	}
+	if req.TraceID == "" {
+		req.TraceID = newFallbackTraceID()
+	}
+
 	chat := h.chatCaller()
 	validate := func(kind string, artifact map[string]any) (validator.Report, error) {
 		report, vErr, kindErr := h.runValidator(kind, artifact, req.Context)
@@ -239,7 +283,24 @@ func (h *handlers) handleIterate(w http.ResponseWriter, r *http.Request) {
 		return *report, nil
 	}
 
-	resp, fail, err := validator.Iterate(r.Context(), req, h.iterCfg, chat, validate)
+	// Wire per-attempt span emission when Langfuse is configured —
+	// each chat→validate cycle becomes a child span of the iterate
+	// trace, with prompt/raw/verdict captured for inspection.
+	cfg := h.iterCfg
+	if h.lf != nil {
+		cfg.Tracer = h.iterTracer(r.Context())
+	}
+
+	t0 := time.Now()
+	resp, fail, err := validator.Iterate(r.Context(), req, cfg, chat, validate)
+	durationMs := time.Since(t0).Milliseconds()
+
+	// Emit one session row regardless of success/failure/infra-error.
+	// Best-effort: a failing session log never blocks the response.
+	rosterCheck := h.rosterCheckFor(req.Kind)
+	rec := validator.BuildSessionRecord(req, resp, fail, err, rosterCheck, durationMs)
+	h.sessionLog.Append(rec)
+
 	if err != nil {
 		http.Error(w, err.Error(), http.StatusBadGateway)
 		return
@@ -251,11 +312,64 @@ func (h *handlers) handleIterate(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, resp)
 }
 
+// rosterCheckFor returns a closure that verifies an accepted artifact's
+// candidate IDs all exist in the roster. Used by BuildSessionRecord to
+// stamp `grounded_in_roster` on each session row — answers the "did
+// the model produce real workers, not phantoms?" question at offline-
+// query time.
+//
+// Only the `fill` kind has worker IDs to verify. Other kinds return
+// nil (omits the field from the session record).
+//
+// Note: FillValidator already enforces this constraint on every
+// successful iteration (phantom IDs raise ValidationError::Consistency).
+// Stamping the bool here surfaces the verified-grounded property as
+// queryable data, not relying on validator semantics being recalled
+// during analysis. A future scrum may want to query "show me sessions
+// where the model guessed real worker IDs without ever needing a
+// retry" — that's a `iterations=1 AND grounded_in_roster=true` query.
+func (h *handlers) rosterCheckFor(kind string) func(map[string]any) *bool {
+	if kind != "fill" {
+		return nil
+	}
+	return func(artifact map[string]any) *bool {
+		fills, ok := artifact["fills"].([]any)
+		if !ok {
+			f := false
+			return &f
+		}
+		for _, raw := range fills {
+			fill, ok := raw.(map[string]any)
+			if !ok {
+				f := false
+				return &f
+			}
+			id, _ := fill["candidate_id"].(string)
+			if id == "" {
+				f := false
+				return &f
+			}
+			if _, found := h.lookup.Find(id); !found {
+				f := false
+				return &f
+			}
+		}
+		t := true
+		return &t
+	}
+}
+
 // chatCaller wires the iteration loop to chatd via HTTP. Builds the
 // chat.Request shape, posts to ${chatdURL}/chat, returns the content
 // string (no choices wrapper — chatd's response is already flat).
+//
+// When traceID is non-empty, forwards it as the `X-Lakehouse-Trace-Id`
+// header so chatd's middleware attaches its trace to the same
+// Langfuse parent. Closes the multi-call observability gap: a
+// /v1/iterate session shows in Langfuse as one trace with N child
+// chat spans, instead of N+1 disconnected traces.
 func (h *handlers) chatCaller() validator.ChatCaller {
-	return func(ctx context.Context, system, user, _, model string, temp *float64, maxTokens int) (string, error) {
+	return func(ctx context.Context, system, user, _, model string, temp *float64, maxTokens int, traceID string) (string, error) {
 		messages := make([]map[string]string, 0, 2)
 		if system != "" {
 			messages = append(messages, map[string]string{"role": "system", "content": system})
@@ -278,6 +392,9 @@ func (h *handlers) chatCaller() validator.ChatCaller {
 			return "", fmt.Errorf("build chat req: %w", err)
 		}
 		req.Header.Set("Content-Type", "application/json")
+		if traceID != "" {
+			req.Header.Set(shared.TraceIDHeader, traceID)
+		}
 		resp, err := h.chatClient.Do(req)
 		if err != nil {
 			return "", fmt.Errorf("chat hop: %w", err)
@@ -297,6 +414,61 @@ func (h *handlers) chatCaller() validator.ChatCaller {
 	}
 }
 
+// iterTracer adapts validator.Tracer → langfuse.Client.Span. Each
+// iteration attempt becomes one Langfuse span on the parent trace
+// with input={prompt, model, provider}, output={raw, verdict}.
+// Operators reading Langfuse can scroll the iterate session and see
+// the full retry chain — which prompt produced which raw, which
+// validator verdict landed, which retry the model recovered on.
+//
+// Returns the span id so it lands in IterateAttempt.SpanID — the
+// /v1/iterate response carries that id back to the caller for log
+// correlation.
+//
+// Errors are silent (best-effort posture per package langfuse). A
+// dropped span never blocks the iterate loop.
+func (h *handlers) iterTracer(ctx context.Context) validator.Tracer {
+	return func(s validator.AttemptSpan) string {
+		level := "DEFAULT"
+		if s.Verdict.Kind != "accepted" {
+			level = "WARNING"
+		}
+		return h.lf.Span(ctx, langfuse.SpanInput{
+			TraceID: s.TraceID,
+			Name:    fmt.Sprintf("iterate.attempt[%d]", s.Iteration),
+			Input: map[string]any{
+				"iteration": s.Iteration,
+				"model":     s.Model,
+				"provider":  s.Provider,
+				"prompt":    trim(s.Prompt, 4000),
+			},
+			Output: map[string]any{
+				"verdict": s.Verdict.Kind,
+				"error":   s.Verdict.Error,
+				"raw":     trim(s.Raw, 4000),
+			},
+			Metadata: map[string]any{
+				"verdict_error": s.Verdict.Error,
+			},
+			StartTime: s.StartTime,
+			EndTime:   s.EndTime,
+			Level:     level,
+		})
+	}
+}
+
+// newFallbackTraceID generates a time-ordered hex id used when no
+// upstream trace id was forwarded AND the langfuse middleware didn't
+// mint one (Langfuse unconfigured). Same shape Langfuse accepts so
+// future Langfuse-enabled deployments don't break correlation. Avoids
+// pulling in a uuid crate dep; nanosecond precision + a randomness
+// suffix is unique enough at the rates iterate runs.
+func newFallbackTraceID() string {
+	ns := time.Now().UTC().UnixNano()
+	rand := uint32(time.Now().UnixNano() % (1 << 32))
+	return fmt.Sprintf("%016x-%08x", ns, rand)
+}
+
 func writeJSON(w http.ResponseWriter, status int, body any) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(status)

cmd/validatord/main_test.go

@@ -1,10 +1,13 @@
 package main
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"os"
+	"path/filepath"
 	"testing"
 	"time"
 
@@ -13,11 +16,47 @@ import (
 	"git.agentview.dev/profit/golangLAKEHOUSE/internal/validator"
 )
 
+// readSessionLog parses the JSONL session log into row maps. Used by
+// the iterate-handler tests to verify per-session entries.
+func readSessionLog(t *testing.T, path string) []map[string]any {
+	t.Helper()
+	f, err := os.Open(path)
+	if err != nil {
+		t.Fatalf("open session log: %v", err)
+	}
+	defer f.Close()
+	var out []map[string]any
+	sc := bufio.NewScanner(f)
+	sc.Buffer(make([]byte, 0, 1<<16), 1<<24)
+	for sc.Scan() {
+		line := sc.Bytes()
+		if len(line) == 0 {
+			continue
+		}
+		var row map[string]any
+		if err := json.Unmarshal(line, &row); err != nil {
+			t.Fatalf("parse session log line: %v", err)
+		}
+		out = append(out, row)
+	}
+	return out
+}
+
 // newTestRouter builds the validatord router with an explicit lookup
 // + a fake chatd URL. Tests that exercise /iterate need a live mock
 // chatd (constructed inline per-test).
 func newTestRouter(lookup validator.WorkerLookup, chatdURL string) http.Handler {
-	h := &handlers{
+	h := newTestHandlers(lookup, chatdURL, nil)
+	r := chi.NewRouter()
+	h.register(r)
+	return r
+}
+
+// newTestHandlers exposes the underlying handlers struct so tests can
+// inspect post-call state (e.g. session log contents). sessionLog is
+// optional — pass nil to disable the session log.
+func newTestHandlers(lookup validator.WorkerLookup, chatdURL string, sessionLog *validator.SessionLogger) *handlers {
+	return &handlers{
 		lookup:     lookup,
 		chatdURL:   chatdURL,
 		chatClient: &http.Client{Timeout: 5 * time.Second},
@@ -25,10 +64,8 @@ func newTestRouter(lookup validator.WorkerLookup, chatdURL string) http.Handler
 			DefaultMaxIterations: 3,
 			DefaultMaxTokens:     4096,
 		},
+		sessionLog: sessionLog,
 	}
-	r := chi.NewRouter()
-	h.register(r)
-	return r
 }
 
 // ─── /validate ─────────────────────────────────────────────────
@@ -244,6 +281,135 @@ func TestIterate_MaxIterReturns422WithHistory(t *testing.T) {
 	}
 }
 
+// TestIterate_WritesSessionRowOnSuccess locks the offline-analysis
+// contract: every successful /iterate call appends one SessionRecord
+// to the configured JSONL with grounded_in_roster=true (because the
+// model emitted real candidate IDs that exist in the roster).
+func TestIterate_WritesSessionRowOnSuccess(t *testing.T) {
+	city, role := "Toledo", "Welder"
+	lookup := validator.NewInMemoryWorkerLookup([]validator.WorkerRecord{
+		{CandidateID: "W-1", Name: "Ada", Status: "active", City: &city, Role: &role},
+	})
+	server := fakeChatd(t, `{"fills":[{"candidate_id":"W-1","name":"Ada"}]}`)
+	defer server.Close()
+
+	dir := t.TempDir()
+	logPath := filepath.Join(dir, "sessions.jsonl")
+	h := newTestHandlers(lookup, server.URL, validator.NewSessionLogger(logPath))
+	r := chi.NewRouter()
+	h.register(r)
+
+	body, _ := json.Marshal(map[string]any{
+		"kind":     "fill",
+		"prompt":   "produce fill",
+		"provider": "ollama",
+		"model":    "qwen3.5:latest",
+		"context":  map[string]any{"target_count": 1, "city": "Toledo", "role": "Welder", "client_id": "C-1"},
+	})
+	req := httptest.NewRequest("POST", "/iterate", bytes.NewReader(body))
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d (body=%s)", w.Code, w.Body.String())
+	}
+
+	rows := readSessionLog(t, logPath)
+	if len(rows) != 1 {
+		t.Fatalf("expected 1 session row, got %d", len(rows))
+	}
+	row := rows[0]
+	if row["schema"] != validator.SessionRecordSchema {
+		t.Errorf("schema: %v", row["schema"])
+	}
+	if row["final_verdict"] != "accepted" {
+		t.Errorf("final_verdict: %v", row["final_verdict"])
+	}
+	if row["grounded_in_roster"] != true {
+		t.Errorf("grounded_in_roster: expected true (W-1 is in roster), got %v", row["grounded_in_roster"])
+	}
+	if row["kind"] != "fill" {
+		t.Errorf("kind: %v", row["kind"])
+	}
+}
+
+// TestIterate_GroundedFalseWhenArtifactReferencesPhantom is the
+// load-bearing forensic property J flagged 2026-05-02: phantom
+// worker IDs in the final accepted artifact must surface as
+// grounded_in_roster=false in the session log. This shouldn't happen
+// in practice (FillValidator catches phantoms before they reach this
+// row), but the explicit check guards against a future bug where the
+// validator weakens or a different validator path skips the roster
+// check. Defense-in-depth at the observability layer.
+func TestIterate_GroundedFalseWhenArtifactReferencesPhantom(t *testing.T) {
+	// Empty roster — every candidate ID is "phantom". Plus we use
+	// the playbook kind so the validator doesn't reject the artifact
+	// upfront (PlaybookValidator doesn't consult the roster), letting
+	// the artifact reach the session log. We then build a custom
+	// rosterCheckFor "fill" closure and exercise it directly.
+	lookup := validator.NewInMemoryWorkerLookup(nil)
+	h := newTestHandlers(lookup, "", nil)
+	check := h.rosterCheckFor("fill")
+	if check == nil {
+		t.Fatal("expected non-nil checker for fill kind")
+	}
+	got := check(map[string]any{
+		"fills": []any{
+			map[string]any{"candidate_id": "W-PHANTOM-NEVER-EXISTS"},
+		},
+	})
+	if got == nil || *got {
+		t.Errorf("expected grounded=false for phantom candidate, got %v", got)
+	}
+	// Other kinds: no roster concept → checker returns nil.
+	if h.rosterCheckFor("email") != nil {
+		t.Error("email kind should not have a roster checker")
+	}
+	if h.rosterCheckFor("playbook") != nil {
+		t.Error("playbook kind should not have a roster checker")
+	}
+}
+
+// TestIterate_WritesSessionRowOnFailure: max-iter exhaustion still
+// produces a row (omits artifact, captures the retry chain).
+func TestIterate_WritesSessionRowOnFailure(t *testing.T) {
+	server := fakeChatd(t, "no json here, just prose")
+	defer server.Close()
+
+	dir := t.TempDir()
+	logPath := filepath.Join(dir, "sessions.jsonl")
+	h := newTestHandlers(validator.NewInMemoryWorkerLookup(nil), server.URL,
+		validator.NewSessionLogger(logPath))
+	r := chi.NewRouter()
+	h.register(r)
+
+	body, _ := json.Marshal(map[string]any{
+		"kind":           "playbook",
+		"prompt":         "produce X",
+		"provider":       "ollama",
+		"model":          "x",
+		"max_iterations": 2,
+	})
+	req := httptest.NewRequest("POST", "/iterate", bytes.NewReader(body))
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusUnprocessableEntity {
+		t.Fatalf("expected 422, got %d", w.Code)
+	}
+
+	rows := readSessionLog(t, logPath)
+	if len(rows) != 1 {
+		t.Fatalf("expected 1 session row, got %d", len(rows))
+	}
+	if rows[0]["final_verdict"] != "max_iter_exhausted" {
+		t.Errorf("final_verdict: %v", rows[0]["final_verdict"])
+	}
+	if _, hasArtifact := rows[0]["artifact"]; hasArtifact {
+		t.Errorf("artifact should be omitted on failure: %v", rows[0]["artifact"])
+	}
+}
+
 func TestIterate_ChatdDownReturns502(t *testing.T) {
 	r := newTestRouter(validator.NewInMemoryWorkerLookup(nil), "http://127.0.0.1:1") // unroutable
 	body, _ := json.Marshal(map[string]any{

docs/ARCHITECTURE_COMPARISON.md

@@ -4,7 +4,7 @@
 > comparison.
 > **Owner**: J. Update this when either side ships a fix that changes
 > the table values, or when a new architectural axis surfaces.
-> **Last meaningful refresh**: 2026-05-01 (post-Rust-cache + Go-validator-port)
+> **Last meaningful refresh**: 2026-05-02 (post-Lance-gauntlet + observability parity)
 
 This document compares the two parallel implementations of the lakehouse
 substrate — Rust at `/home/profit/lakehouse/` (production today), Go at
@@ -48,13 +48,19 @@ Don't:
 | 2026-05-01 | Multi-tier load test against 100k corpus | 335k scenarios in 5min, 4/6 at 0% fail. Surfaced coder/hnsw v0.6.1 bug. Recover guard added. **DONE** (multitier_100k.md). |
 | 2026-05-01 | **coder/hnsw v0.6.1 panic — REAL FIX landed** | Lifted source-of-truth out of coder/hnsw via `i.vectors map[string][]float32` side store + `safeGraphAdd`/`safeGraphDelete` recover wrappers + warm-path rebuild fallback. Re-run: 0 failures across 19,622 scenarios (was 96-98% on 2/6). **DONE.** Architecture invariant in STATE_OF_PLAY "DO NOT RELITIGATE". |
 | 2026-05-02 | **Substrate fix verified at original failure scale** | Re-ran multitier 5min @ conc=50 (the footprint that originally surfaced the bug at 96-98% fail). Result: 132,211 scenarios at 438/sec, **6/6 classes at 0% failure**. Throughput dropped 1,115/sec → 438/sec because broken scenarios now do real HNSW Add work. Tails healthy: surge_fill_validate p99=1.53s, playbook_record_replay p99=2.32s. **Fix scales — closing the open thread.** |
-| _open_ | Drop Python sidecar from Rust aibridge | Universal-win architectural cleanup. ~200 LOC, removes 1 runtime + 1 process. |
+| 2026-05-02 | **Drop Python sidecar from Rust aibridge — DONE** | `crates/aibridge/src/client.rs` rewrite (commit `ba928b1` in lakehouse). AiClient now talks Ollama directly: per-text `/api/embed` loop, `/api/generate` for chat + rerank-loop + admin (unload/preload), `/api/ps` + `std::process::Command nvidia-smi` for vram_snapshot. Public API unchanged — 0 callers updated. Verification: cargo test -p aibridge 32/32 PASS, live smoke `/ai/embed` returns 768-dim vector + `/v1/chat` returns "OK". Sidecar's `lab_ui.py` + `pipeline_lab.py` (~888 LOC dev-only UIs) keep running; only the hot-path embed/generate/rerank/admin routes are retired. Process count drops from "mega-binary + sidecar" to "mega-binary alone". |
+| 2026-05-02 | **Rust observability parity (trace-id + session JSONL) — DONE** | Mirrors the Go-side wave (commits `d6d2fdf` + `1a3a82a` in golangLAKEHOUSE). `crates/gateway/src/v1/iterate.rs` now reads `X-Lakehouse-Trace-Id` header, forwards to `/v1/chat` + `/v1/validate` hops, emits per-attempt Langfuse spans (`iterate.attempt[N]`), and writes one `SessionRecord` JSONL row per session via the new `crates/gateway/src/v1/session_log.rs` writer. New `crates/gateway/src/bin/parity_session_log` helper enables the cross-runtime parity probe at `scripts/cutover/parity/session_log_parity.sh` — **4/4 fixtures byte-equal** (including unicode prompts) after normalizing the 2 fields that legitimately differ (timestamp, daemon name). Both runtimes can write to the same path and DuckDB queries see them as one stream. 90/90 Rust unit tests PASS, 33 Go packages PASS. |
+| 2026-05-02 | **Cross-runtime parity gap closure — DONE** | Two follow-ups from the deploy + reality wave: (1) Go validatord didn't honor `X-Lakehouse-Trace-Id` when Langfuse middleware was a passthrough (no env config) — fixed by reading the header DIRECTLY in the iterate handler before the ctx fallback (Go commit `6847bbc`). (2) Rust `IterateResponse`/`IterateFailure` didn't echo `trace_id` back to callers — added the field with skip-serializing-if-none for backward compat (Rust commit `98b6647`). Plus enabled `[gateway].session_log_path` on live Rust pointing at the SAME path Go writes to, so DuckDB queries see one unified longitudinal log. **Verified end-to-end**: identical /v1/iterate to both runtimes lands in one sessions.jsonl tagged `daemon=gateway` (Rust) vs `daemon=validatord` (Go); response bodies both echo the forwarded trace_id. 24/24 parity assertions (validator+extract_json+session_log+materializer) hold post-restart. |
 | 2026-05-02 | **Port Rust materializer to Go (transforms.ts) — DONE** | `internal/materializer` + `cmd/materializer` + `materializer_smoke.sh`. Ports `transforms.ts` (12 transforms) + `build_evidence_index.ts`. Idempotency, day-partition, receipt. 14 tests green; on-wire JSON matches TS so both runtimes interoperate. |
 | 2026-05-02 | **Port Rust replay tool to Go — DONE** | `internal/replay` + `cmd/replay` + `replay_smoke.sh`. Ports `replay.ts` retrieve → bundle → /v1/chat → validate → log. Closes audit-FULL phase 7 live invocation on Go side. 14 tests green; same `data/_kb/replay_runs.jsonl` shape (schema=replay_run.v1) as TS. |
 | 2026-05-02 | **`/v1/validate` + `/v1/iterate` HTTP surface — DONE** | `cmd/validatord` (port 3221) hosts both endpoints. `internal/validator` gains `PlaybookValidator` (3rd kind), JSONL roster loader, and the `Iterate` orchestrator + `ExtractJSON` helper. Gateway proxies `/v1/validate` + `/v1/iterate` to validatord. Closes the last "Go-primary" backlog item (architecture_comparison.md item #7). 30+ tests + `validatord_smoke.sh` 5/5 PASS. |
 | 2026-05-02 | **Cross-runtime validator parity probe — surfaced wire-format gap** | New `scripts/cutover/parity/validator_parity.sh` runs 6 identical /v1/validate cases against Rust :3100 AND Go :4110, compares status + body. Result: **6/6 status codes match (logic-level equivalence holds), 5/6 body shapes diverge.** Rust returns serde-tagged enum `{"Schema":{"field":"x","reason":"y"}}`; Go returns flat struct `{"Kind":"schema","Field":"x","Reason":"y"}`. Any caller parsing the error envelope would break in cutover. **Open**: pick a target shape (Go matching Rust is the cutover-friendly direction) and align via custom `MarshalJSON` on `ValidationError`. |
-| _open_ | **Validator wire-format alignment** | Surfaced by 2026-05-02 parity probe. Choose canonical error JSON shape, align both runtimes. ~50 LOC custom `MarshalJSON` either side. |
-| _open_ | Decide on Lance vector backend | Defer until corpus exceeds ~5M rows. |
+| 2026-05-02 | **Materializer parity probe — caught + fixed real bug** | New `scripts/cutover/parity/materializer_parity.sh` runs Bun + Go materializer on identical synthetic root, diffs output JSONL. Result on first run: **0/2 match** — Go's `Provenance.LineOffset` had `json:",omitempty"` and stripped the field on first-row records (line_offset=0 is semantically meaningful, not absent). 1-line fix (drop `omitempty` + comment explaining why). Re-run: **2/2 match**. Real cross-runtime gap surfaced + closed in same wave. |
+| 2026-05-02 | **extract_json parity probe — 12/12 match across edge cases** | New `scripts/cutover/parity/extract_json_parity.sh` runs identical model-output strings through Rust `gateway::v1::iterate::extract_json` AND Go `validator.ExtractJSON`. 12 fixtures: fenced/unfenced blocks, nested objects, unicode, escaped quotes, top-level array, malformed JSON. Substrate gate: `cargo test -p gateway extract_json` PASS before probe. Result: **12/12 match.** Algorithms genuinely equivalent. Rust side gained `pub` on `extract_json` + new `bin/parity_extract_json` (~30 LOC). |
+| 2026-05-02 | **Validator wire-format alignment — DONE** | Custom `MarshalJSON`/`UnmarshalJSON` on Go's `validator.ValidationError` emits the Rust serde-tagged-enum shape `{"Schema":{"field":"x","reason":"y"}}`. UnmarshalJSON also accepts the legacy flat shape (migration safety) and rejects unknown variants (drift guard for future Rust enum additions). 4 new pinning tests in `types_test.go`. Re-run validator parity probe: **6/6 match** (was 1/6). |
+| 2026-05-02 | **Lance backend gauntlet (4-pack + root-cause fix) — DONE** | Lance crate had zero tests + no smoke when audited this morning. Shipped: (a) `sanitize_lance_err` over all 5 routes (search/doc/index/append/migrate) — missing-index now 404 not 500, no `/home/` or `/root/.cargo/` paths leaked; (b) 7 unit tests in `crates/vectord-lance` with synth Parquet helper; (c) 9-probe `scripts/lance_smoke.sh` against live `:3100`; (d) 10M re-bench (`reports/lance_10m_rebench_2026-05-02.md`) — search warm ~20ms, search cold ~46ms median. Bench surfaced doc-fetch p50 ~100ms (300x slower than ADR-019 100K projection); root-caused to lance-bench bypassing IndexMeta → warming auto-build never fired → no `doc_id` btree. **Fix shipped (commit `5d30b3d`)**: `lance_migrate` HTTP handler now auto-builds the btree inline (1.2s on 10M, +269MB), drops doc-fetch to ~5ms (20x). Live verified 9/9 smoke + post-restart doc-fetch 4-15ms. |
+| 2026-05-03 | **Subject manifests + per-subject HMAC audit log — DONE on Rust + Go** | Local-first compliance substrate per `lakehouse/docs/specs/SUBJECT_MANIFESTS_ON_CATALOGD.md` Steps 1-8. Rust shipped: `SubjectManifest` type + Registry CRUD (`crates/catalogd/src/registry.rs`), `SubjectAuditWriter` with HMAC-SHA256 chain + per-subject Mutex serialization + canonical-JSON via BTreeMap (`subject_audit.rs`), backfill ETL (`bin/backfill_subjects`), gateway tool dispatch + validator decorator wiring, legal-tier `/audit/subject/{id}` endpoint with constant-time-eq token + tampering detection, daily `bin/retention_sweep` (BIPA-aware, idempotent, no auto-mutation). Go shipped: identical `internal/catalogd/subject.go` reader + `VerifyChain` over RAW LINE BYTES (avoids time-precision drift), 11 unit tests. **6th cross-runtime parity probe**: `scripts/cutover/parity/subject_audit_parity.sh` — 6/6 byte-identical assertions across known-answer fixture + 5 real production audit logs. Surfaced + closed three drift classes in authoring loop: (1) Go `omitempty` stripping `trace_id:""`; (2) `time.RFC3339Nano` truncating trailing-zero nanoseconds where chrono AutoSi keeps 9 digits; (3) Go `json.Marshal` HTML-escaping `<>&` where serde keeps literal — fixed via `marshalNoEscapeHTML` + raw-bytes canonicalization. Two cross-lineage scrums caught real bugs each round (chain corruption race, schema-evolution HMAC drift, hardcoded "success" classifier, token min length, chain_root from windowed slice, tampering detection, HTML escape divergence). |
+| _open_ | Decide Lance vs Parquet+HNSW for primary | Lance verified production-ready at 10M (this morning's gauntlet). HNSW at 10M doesn't fit RAM (~60GB for vectors+graph), so the comparison is between Lance and Parquet+HNSW-with-spilling. Decide once we have a 10M ingest scenario where the Parquet path is bottlenecked. |
 | _open_ | Pick Go primary vs Rust primary | Both viable. Go has perf edge after today; Rust has production deploy + producer-side completeness. |
 
 ---
@@ -95,17 +101,24 @@ up). Go also lets you tune per-daemon resource limits via systemd.
 
 ## Python dependency (the load-bearing axis)
 
-This is the architectural difference that drove the original perf gap.
-Both call Ollama at `:11434`, but the path differs:
+This was the architectural difference that drove the original perf gap.
 
 ```
+Pre-2026-05-02:
   Rust embed:  gateway → HTTP → Python sidecar :3200 → HTTP → Ollama :11434
   Go embed:    gateway → HTTP → Go embedd      :4216 → HTTP → Ollama :11434
+
+Post-2026-05-02 (commit ba928b1):
+  Rust embed:  gateway → HTTP → Ollama :11434                (sidecar dropped)
+  Go embed:    gateway → HTTP → Go embedd :4216 → HTTP → Ollama :11434
 ```
 
-The Python sidecar (`sidecar/sidecar/main.py`, 1,237 lines) is a
-FastAPI wrapper around Ollama. It does pydantic validation + request
-shaping; **no fundamental compute** that Ollama can't do directly.
+The hot-path Python sidecar (~120 LOC across embed.py / generate.py
+/ rerank.py / admin.py) was pure pass-through to Ollama and added no
+logic — just translation. AiClient was rewritten 2026-05-02 to call
+Ollama directly. `lab_ui.py` + `pipeline_lab.py` (~888 LOC of
+Streamlit-shape dev UIs) remain as ad-hoc tooling, not on the
+runtime hot path.
 
 ### Performance impact (load-tested 2026-05-01, 6 rotating bodies, 10 concurrency, 30s)
 
@@ -268,7 +281,7 @@ The list below is a working backlog. Move items to "Decisions tracker"
 
 1. ✅ **Embed cache in Rust aibridge** — DONE 2026-05-01 (`150cc3b`).
 2. ✅ **FillValidator + EmailValidator in Go** — DONE 2026-05-01 (`b03521a`).
-3. **Drop Python sidecar from Rust** — Rewrite aibridge to call Ollama at `:11434/api/embed` and `/api/generate` directly. Removes 1 runtime + 1 process from ops. ~200 LOC.
+3. ✅ **Drop Python sidecar from Rust** — DONE 2026-05-02 (`ba928b1`).
 4. **Cross-runtime contract tests** — Pin shared JSONL schemas (audit_baselines, scored_run, sft_sample) as canonical specs in `auditor/schemas/` with Go-side validators consuming the same definitions.
 
 ### If keeping Go primary
@@ -318,6 +331,7 @@ Append entries here when this doc gets updated. One-line entries; link to commit
 - 2026-05-02 — Substrate fix verified at original failure-surfacing scale. Multitier 5min @ conc=50: 132,211 scenarios at 438/sec, 6/6 classes at 0% failure (was 4/6 pre-fix). Throughput drop (1,115 → 438/sec) is the honest cost of the formerly-broken scenarios doing real HNSW Add work. STATE_OF_PLAY refreshed to 2026-05-02.
 - 2026-05-02 — Materializer + replay tool ported from Rust legacy to Go (`internal/materializer` + `internal/replay`, both with CLI + smoke + tests). Both runtimes now produce the same `data/evidence/YYYY/MM/DD/*.jsonl` and `data/_kb/replay_runs.jsonl` shapes; Go side no longer needs Bun for these phases.
 - 2026-05-02 — `/v1/validate` + `/v1/iterate` HTTP surface ported as `cmd/validatord` on `:3221`. Closes the last "If keeping Go primary" backlog item — Go now owns the entire validator path end-to-end (no Rust dep for staffing safety net). 5/5 smoke probes via gateway :3110.
+- 2026-05-02 — Python sidecar dropped from Rust hot path (`ba928b1`). AiClient now talks Ollama directly. Process count: mega-binary + sidecar → mega-binary alone. Public API unchanged, 0 callers updated. Cargo tests 32/32 PASS, live `/ai/embed` + `/v1/chat` smokes green on test gateway. Lab UI Python remains as ad-hoc dev tooling.
 
 ---
 

docs/SESSION_LOG.md

@@ -0,0 +1,158 @@
+# Coordinator session log — `coordinator_sessions.jsonl`
+
+**Last updated:** 2026-05-02 · **Schema:** `session.iterate.v1` · **Writer:** `internal/validator.SessionLogger` · **Producer:** validatord `/v1/iterate`
+
+## Why
+
+The Langfuse trace tree is the live view: per-session, you can scroll
+the retry chain and inspect every sub-call. But for **longitudinal
+forensics** ("show me every session in the last week where the model
+guessed a real worker without a retry," or "find sessions where
+validation rejected three times in a row"), Langfuse's UI doesn't
+scale — you need a queryable data plane.
+
+This JSONL is that plane. One row per `/v1/iterate` session, append-
+only, DuckDB-friendly.
+
+## Where
+
+Configurable via `[validatord].session_log_path` in `lakehouse.toml`.
+Empty = disabled (best-effort posture; a missing log never blocks an
+iterate request). Production:
+
+```toml
+[validatord]
+session_log_path = "/var/lib/lakehouse/validator/sessions.jsonl"
+```
+
+## Schema (v1)
+
+```jsonc
+{
+  "schema":          "session.iterate.v1",
+  "session_id":      "<Langfuse trace_id>",      // join key to Langfuse
+  "timestamp":       "2026-05-02T07:30:00.123456Z",
+  "daemon":          "validatord",
+  "kind":            "fill | email | playbook",
+  "model":           "qwen3.5:latest",
+  "provider":        "ollama",
+  "prompt":          "produce a fill artifact ...",  // truncated to 4000 chars
+  "iterations":      3,                              // attempts spent
+  "max_iterations":  3,                              // cap per request
+  "final_verdict":   "accepted | max_iter_exhausted | infra_error",
+  "attempts": [
+    { "iteration": 0, "verdict_kind": "validation_failed",
+      "error": "consistency: candidate_id W-X not in roster",
+      "span_id": "abc..." },
+    { "iteration": 1, "verdict_kind": "validation_failed",
+      "error": "consistency: city mismatch", "span_id": "def..." },
+    { "iteration": 2, "verdict_kind": "accepted", "span_id": "ghi..." }
+  ],
+  "artifact":        { /* final accepted artifact, omitted on failure */ },
+  "grounded_in_roster": true,                       // null when N/A (email/playbook)
+  "duration_ms":     2840
+}
+```
+
+### Field semantics
+
+| Field | When set | What it means |
+|---|---|---|
+| `session_id` | always | Langfuse trace id. Pivot to live trace tree by URL: `${LANGFUSE_URL}/trace/<session_id>`. |
+| `final_verdict=accepted` | success | Loop converged within `max_iterations`. `artifact` is non-null. |
+| `final_verdict=max_iter_exhausted` | failure | Loop hit the cap without passing validation. `artifact` is omitted. |
+| `final_verdict=infra_error` | failure | Chat hop or other infra crashed. Single attempt with `verdict_kind=infra_error`. |
+| `grounded_in_roster=true` | fill kind, success | Every `candidate_id` in the artifact exists in `WorkerLookup`. |
+| `grounded_in_roster=false` | fill kind, anomaly | Phantom or otherwise-invalid candidate IDs (shouldn't happen — FillValidator catches these — but the explicit check defends against future validator weakening). |
+| `grounded_in_roster=null` (omitted) | non-fill kinds, or failure | The roster check doesn't apply or wasn't run. |
+
+## DuckDB queries
+
+```sql
+-- Read the log directly via DuckDB's read_json_auto.
+ATTACH ':memory:' AS sessions;
+SELECT * FROM read_json_auto(
+  '/var/lib/lakehouse/validator/sessions.jsonl', format='newline_delimited'
+) LIMIT 10;
+```
+
+### "Did the validator catch every phantom worker?"
+```sql
+-- Sessions where iteration 0's verdict was validation_failed AND
+-- the error mentions 'phantom' or 'consistency'. If grounded=true on
+-- the same session's final state, the model recovered.
+SELECT session_id, model, iterations, grounded_in_roster, final_verdict
+FROM read_json_auto('sessions.jsonl', format='newline_delimited')
+WHERE final_verdict = 'accepted'
+  AND iterations > 1
+  AND list_contains(
+        list_transform(attempts,
+          x -> x.error LIKE '%consistency%' OR x.error LIKE '%phantom%'),
+        true
+      );
+```
+
+### "First-shot success rate per model" (the "did the corpus give it enough" gate)
+```sql
+SELECT model,
+       COUNT(*) AS sessions,
+       SUM(CASE WHEN iterations = 1 AND final_verdict = 'accepted' THEN 1 ELSE 0 END) AS first_shot,
+       ROUND(100.0 * SUM(CASE WHEN iterations = 1 AND final_verdict = 'accepted' THEN 1 ELSE 0 END) / COUNT(*), 1) AS pct
+FROM read_json_auto('sessions.jsonl', format='newline_delimited')
+WHERE kind = 'fill'
+GROUP BY model
+ORDER BY pct DESC;
+```
+
+### "Sessions that were never grounded" (the alarm query)
+```sql
+-- Should always be empty. If it isn't, FillValidator has a hole or
+-- a different code path is bypassing the roster check.
+SELECT session_id, model, iterations, attempts
+FROM read_json_auto('sessions.jsonl', format='newline_delimited')
+WHERE kind = 'fill'
+  AND final_verdict = 'accepted'
+  AND grounded_in_roster = false;
+```
+
+### "Average retry depth per model"
+```sql
+SELECT model, AVG(iterations) AS avg_iter, COUNT(*) AS n
+FROM read_json_auto('sessions.jsonl', format='newline_delimited')
+WHERE kind = 'fill' AND final_verdict = 'accepted'
+GROUP BY model
+ORDER BY avg_iter ASC;
+```
+
+### "What did validation reject?" (failure mode breakdown)
+```sql
+-- Pull each rejected attempt's error string, classify by prefix.
+WITH errors AS (
+  SELECT session_id,
+         model,
+         unnest(attempts) AS att
+  FROM read_json_auto('sessions.jsonl', format='newline_delimited')
+)
+SELECT model,
+       split_part(att.error, ':', 1) AS kind,
+       COUNT(*) AS n
+FROM errors
+WHERE att.verdict_kind = 'validation_failed'
+GROUP BY model, kind
+ORDER BY n DESC;
+```
+
+## Operational notes
+
+- **Append-only.** No row is ever updated; storage grows linearly with iterate calls. Operators rotate via cron when the file gets unwieldy (logrotate-style).
+- **Best-effort posture.** Every write goes through `slog.Warn` on failure but never blocks the iterate handler. A full disk silently drops session rows; the iterate response still ships.
+- **Schema versioning.** `schema=session.iterate.v1` is the contract. Future incompatible changes bump the version; consumers should branch on the field.
+- **PII consideration.** `prompt` is captured truncated to 4000 chars and the final `artifact` (when present) is captured verbatim. Operators handling PII-bearing prompts should set the path under a restricted-access volume or filter before retention.
+- **Cross-runtime parity.** The Rust gateway's `/v1/iterate` does NOT yet write this file. If you want a unified longitudinal log across runtimes, port the writer to Rust (`crates/gateway/src/v1/iterate.rs`) and target the same JSONL path. ~50 LOC.
+
+## See also
+
+- `internal/validator/session_log.go` — writer + record types
+- `internal/validator/iterate.go` — `Tracer` callback + Langfuse span emission
+- `internal/shared/langfuse_middleware.go` — `X-Lakehouse-Trace-Id` header propagation (the `session_id` join key)
+- `data/_kb/replay_runs.jsonl` — the *replay* tool's own JSONL (different shape, different producer); these two streams are siblings, not duplicates

internal/catalogd/subject.go

@@ -0,0 +1,371 @@
+// Subject manifests + per-subject audit-log chain verification.
+//
+// Specification: /home/profit/lakehouse/docs/specs/SUBJECT_MANIFESTS_ON_CATALOGD.md.
+//
+// This file is the Go side of Step 8 (cross-runtime parity). The Rust
+// side is the writer (crates/catalogd/src/subject_audit.rs); Go is a
+// READER + VERIFIER only — both sides serialize / hash with identical
+// algorithms so a chain written by Rust verifies under Go.
+//
+// Algorithm (must match Rust crates/catalogd/src/subject_audit.rs exactly):
+//   row_hmac = HMAC-SHA256(key, prev_chain_hash_bytes || canonical_row_bytes)
+//
+// where:
+//   - prev_chain_hash_bytes is the ASCII bytes of the previous row's
+//     row_hmac field, OR the literal ASCII string "GENESIS" for the
+//     first row (no hex decode!)
+//   - canonical_row_bytes is the row JSON with the row_hmac field
+//     dropped, with all object keys sorted alphabetically at every
+//     nesting depth, with no insignificant whitespace
+//   - the final hash is rendered as 64 lowercase hex characters
+package catalogd
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"os"
+	"sort"
+	"strings"
+	"time"
+)
+
+const GenesisHash = "GENESIS"
+
+// SubjectManifest mirrors crates/shared/src/types.rs::SubjectManifest.
+// Keep field tags byte-identical so manifest JSON written by Rust round-trips.
+//
+// Vertical: omitempty matches Rust's serde-default deserializer accepting
+// missing field (default Unknown). For the OTHER fields we deliberately
+// avoid omitempty since Rust always emits them.
+type SubjectManifest struct {
+	Schema              string                `json:"schema"`
+	CandidateID         string                `json:"candidate_id"`
+	CreatedAt           time.Time             `json:"created_at"`
+	UpdatedAt           time.Time             `json:"updated_at"`
+	Status              string                `json:"status"`
+	Vertical            string                `json:"vertical,omitempty"`
+	Consent             SubjectConsent        `json:"consent"`
+	Retention           SubjectRetention      `json:"retention"`
+	Datasets            []SubjectDatasetRef   `json:"datasets"`
+	SafeViews           []string              `json:"safe_views"`
+	AuditLogPath        string                `json:"audit_log_path"`
+	AuditLogChainRoot   string                `json:"audit_log_chain_root"`
+	BiometricCollection *BiometricCollection  `json:"biometric_collection,omitempty"`
+}
+
+// BiometricCollection mirrors crates/shared/src/types.rs::BiometricCollection.
+// Written by the Phase 1.6 Gate 3 photo-upload endpoint. None until the
+// first biometric upload; cleared on BIPA erasure.
+type BiometricCollection struct {
+	DataPath            string          `json:"data_path"`
+	TemplateHash        string          `json:"template_hash"`
+	CollectedAt         time.Time       `json:"collected_at"`
+	ConsentVersionHash  string          `json:"consent_version_hash,omitempty"`
+	Classifications     json.RawMessage `json:"classifications,omitempty"`
+}
+
+type SubjectConsent struct {
+	GeneralPii GeneralPiiConsent `json:"general_pii"`
+	Biometric  BiometricConsent  `json:"biometric"`
+}
+
+type GeneralPiiConsent struct {
+	Status       string     `json:"status"`
+	Version      string     `json:"version,omitempty"`
+	GivenAt      *time.Time `json:"given_at,omitempty"`
+	WithdrawnAt  *time.Time `json:"withdrawn_at,omitempty"`
+}
+
+type BiometricConsent struct {
+	Status         string     `json:"status"`
+	RetentionUntil *time.Time `json:"retention_until,omitempty"`
+}
+
+type SubjectRetention struct {
+	GeneralPiiUntil time.Time `json:"general_pii_until"`
+	Policy          string    `json:"policy,omitempty"`
+}
+
+type SubjectDatasetRef struct {
+	Name      string `json:"name"`
+	KeyColumn string `json:"key_column"`
+	KeyValue  string `json:"key_value"`
+}
+
+// SubjectAuditRow mirrors crates/shared/src/types.rs::SubjectAuditRow.
+// JSON field order does NOT matter (canonicalizer sorts at hash time)
+// but field names + types MUST match for round-trip.
+type SubjectAuditRow struct {
+	Schema         string         `json:"schema"`
+	Ts             time.Time      `json:"ts"`
+	CandidateID    string         `json:"candidate_id"`
+	Accessor       AuditAccessor  `json:"accessor"`
+	FieldsAccessed []string       `json:"fields_accessed"`
+	Result         string         `json:"result"`
+	PrevChainHash  string         `json:"prev_chain_hash"`
+	RowHmac        string         `json:"row_hmac"`
+}
+
+// AuditAccessor mirrors crates/shared/src/types.rs::AuditAccessor.
+//
+// IMPORTANT: trace_id has NO omitempty — Rust's serde always writes
+// the field (even empty) because `#[serde(default)]` only affects
+// READS. Stripping it here produces different canonical bytes than
+// the writer used → HMAC mismatch on real production rows. (Caught
+// 2026-05-03 by subject_audit_parity.sh on a live WORKER-1 row with
+// trace_id="".)
+type AuditAccessor struct {
+	Kind    string `json:"kind"`
+	Daemon  string `json:"daemon"`
+	Purpose string `json:"purpose"`
+	TraceID string `json:"trace_id"`
+}
+
+// LoadSubjectManifest reads + parses a subject manifest JSON file.
+func LoadSubjectManifest(path string) (*SubjectManifest, error) {
+	bytes, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("read manifest %s: %w", path, err)
+	}
+	var m SubjectManifest
+	if err := json.Unmarshal(bytes, &m); err != nil {
+		return nil, fmt.Errorf("parse manifest %s: %w", path, err)
+	}
+	return &m, nil
+}
+
+// AuditLogEntry is one parsed audit row PLUS the raw line bytes from
+// the file. The raw bytes are load-bearing: we MUST canonicalize from
+// them (not from the re-marshaled struct) to avoid time-precision drift.
+//
+// Why: Rust's chrono RFC3339-AutoSi serializes nanoseconds with 9 digits
+// (e.g. "461439210"). Go's time.RFC3339Nano strips trailing zeros (e.g.
+// "46143921"). Round-tripping through time.Time changes the byte sequence
+// and breaks the HMAC. Read once, hash from the original bytes.
+// (Caught 2026-05-03 by subject_audit_parity.sh on a real WORKER-5 row
+// whose nanoseconds happened to end in 0.)
+type AuditLogEntry struct {
+	Row SubjectAuditRow
+	Raw []byte
+}
+
+// ReadAuditLog parses an audit JSONL file. Returns one AuditLogEntry
+// per non-empty line. Defensive: blank lines are skipped, unparseable
+// lines are skipped (matches Rust read_rows_in_range).
+func ReadAuditLog(path string) ([]AuditLogEntry, error) {
+	bytes, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, fmt.Errorf("read audit log %s: %w", path, err)
+	}
+	var entries []AuditLogEntry
+	for _, line := range strings.Split(string(bytes), "\n") {
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" {
+			continue
+		}
+		var row SubjectAuditRow
+		if err := json.Unmarshal([]byte(trimmed), &row); err != nil {
+			continue
+		}
+		entries = append(entries, AuditLogEntry{Row: row, Raw: []byte(trimmed)})
+	}
+	return entries, nil
+}
+
+// canonicalRowBytesFromRaw is the production canonicalizer used by
+// VerifyChain. It accepts the raw line bytes from the audit JSONL,
+// drops the row_hmac key, sorts all keys alphabetically at every
+// nesting depth, and re-emits compact JSON. Numbers + strings pass
+// through verbatim (json.Number preserves number text, strings are
+// re-JSON-escaped identically to Rust's serde_json).
+//
+// CRITICAL: hashing must always go through this function. NEVER hash
+// the bytes produced by canonicalRowBytesFromStruct against a real
+// production chain — the time-precision drift will give wrong HMACs
+// for any row whose nanoseconds end in 0.
+func canonicalRowBytesFromRaw(rawLine []byte) ([]byte, error) {
+	dec := json.NewDecoder(strings.NewReader(string(rawLine)))
+	dec.UseNumber()
+	var v any
+	if err := dec.Decode(&v); err != nil {
+		return nil, fmt.Errorf("decode raw line: %w", err)
+	}
+	if obj, ok := v.(map[string]any); ok {
+		delete(obj, "row_hmac")
+	}
+	var buf strings.Builder
+	if err := writeCanonical(&buf, v); err != nil {
+		return nil, err
+	}
+	return []byte(buf.String()), nil
+}
+
+// canonicalRowBytesFromStruct is for the parity probe's known-answer
+// vector + tests where we WANT to canonicalize a Go-built row from
+// scratch (no original bytes exist yet). Production verification uses
+// canonicalRowBytesFromRaw against the file bytes; this function is
+// only safe for synthetic inputs whose ts has no trailing-zero nanos.
+func canonicalRowBytesFromStruct(row *SubjectAuditRow) ([]byte, error) {
+	raw, err := json.Marshal(row)
+	if err != nil {
+		return nil, fmt.Errorf("marshal row: %w", err)
+	}
+	return canonicalRowBytesFromRaw(raw)
+}
+
+// marshalNoEscapeHTML wraps json.Encoder with HTML escaping disabled.
+//
+// Why: Go's json.Marshal escapes `<`, `>`, `&` to `<`, `>`,
+// `&` by default. Rust's serde_json::to_vec keeps them literal.
+// Any string field containing one of those characters would produce
+// different canonical bytes across runtimes → broken HMAC chain.
+// (Caught 2026-05-03 by opus scrum WARN on parity_subject_audit.rs:
+//  canonical_json — initially undetected because no production audit
+//  field contained `<>&`, but realistic for purpose strings like
+//  "error & retry" or trace_id "<HTTP-Request-Id>".)
+//
+// Also strips the trailing newline json.Encoder appends — that newline
+// is meaningful to JSONL consumers but is junk for hash input.
+func marshalNoEscapeHTML(v any) ([]byte, error) {
+	var buf bytes.Buffer
+	enc := json.NewEncoder(&buf)
+	enc.SetEscapeHTML(false)
+	if err := enc.Encode(v); err != nil {
+		return nil, err
+	}
+	out := buf.Bytes()
+	return bytes.TrimRight(out, "\n"), nil
+}
+
+// writeCanonical recursively writes v as canonical JSON: object keys
+// sorted alphabetically, no insignificant whitespace. Arrays preserve
+// element order (semantically significant per spec §3).
+//
+// All scalar emission goes through marshalNoEscapeHTML so the byte
+// sequence matches Rust's serde_json output character-for-character.
+func writeCanonical(buf *strings.Builder, v any) error {
+	switch t := v.(type) {
+	case map[string]any:
+		keys := make([]string, 0, len(t))
+		for k := range t {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+		buf.WriteByte('{')
+		for i, k := range keys {
+			if i > 0 {
+				buf.WriteByte(',')
+			}
+			ks, err := marshalNoEscapeHTML(k)
+			if err != nil {
+				return fmt.Errorf("marshal key: %w", err)
+			}
+			buf.Write(ks)
+			buf.WriteByte(':')
+			if err := writeCanonical(buf, t[k]); err != nil {
+				return err
+			}
+		}
+		buf.WriteByte('}')
+	case []any:
+		buf.WriteByte('[')
+		for i, elem := range t {
+			if i > 0 {
+				buf.WriteByte(',')
+			}
+			if err := writeCanonical(buf, elem); err != nil {
+				return err
+			}
+		}
+		buf.WriteByte(']')
+	default:
+		bs, err := marshalNoEscapeHTML(v)
+		if err != nil {
+			return fmt.Errorf("marshal scalar: %w", err)
+		}
+		buf.Write(bs)
+	}
+	return nil
+}
+
+// CanonicalAndHmac is a helper for the parity probe: canonicalizes the
+// row from scratch (struct → JSON → canonical), computes the HMAC
+// against the given prev_hash, returns both. Used only for the
+// known-answer fixture; production verification uses VerifyChain
+// (which canonicalizes from the original file bytes to dodge time
+// precision drift).
+func CanonicalAndHmac(row *SubjectAuditRow, key []byte, prevHash string) (canonical []byte, hmacHex string, err error) {
+	canonical, err = canonicalRowBytesFromStruct(row)
+	if err != nil {
+		return nil, "", err
+	}
+	hmacHex = computeRowHMAC(key, prevHash, canonical)
+	return canonical, hmacHex, nil
+}
+
+// computeRowHMAC = HMAC-SHA256(key, prev_hash_ascii_bytes || canonical_row_bytes)
+// rendered as 64-char lowercase hex.
+func computeRowHMAC(key []byte, prevHash string, canonical []byte) string {
+	mac := hmac.New(sha256.New, key)
+	mac.Write([]byte(prevHash))
+	mac.Write(canonical)
+	return hex.EncodeToString(mac.Sum(nil))
+}
+
+// VerifyChain replays the chain for a subject's audit log. Returns the
+// number of rows verified, the chain tip (last row's row_hmac, or
+// GENESIS when log is empty), and an error describing the first chain
+// break found.
+//
+// CRITICAL: canonicalizes from each entry's RAW LINE BYTES, not from
+// the parsed struct. Round-tripping through encoding/json + time.Time
+// strips trailing zeros from RFC3339 nanos and produces different
+// canonical bytes than the Rust writer used (which used chrono's
+// AutoSi 9-digit format). Catches: 2026-05-03 WORKER-5 nanos
+// 461439210 → Rust emits 9 digits, Go's time.RFC3339Nano emits 8.
+//
+// Special case: empty/missing log returns (0, GENESIS, nil).
+func VerifyChain(entries []AuditLogEntry, key []byte) (count int, chainTip string, err error) {
+	prev := GenesisHash
+	for i, entry := range entries {
+		if entry.Row.PrevChainHash != prev {
+			return i, prev, fmt.Errorf("chain break at row %d: prev_chain_hash=%q expected=%q",
+				i+1, entry.Row.PrevChainHash, prev)
+		}
+		claimed := entry.Row.RowHmac
+		canonical, cerr := canonicalRowBytesFromRaw(entry.Raw)
+		if cerr != nil {
+			return i, prev, fmt.Errorf("canonicalize row %d: %w", i+1, cerr)
+		}
+		recomputed := computeRowHMAC(key, prev, canonical)
+		if recomputed != claimed {
+			return i, prev, fmt.Errorf("hmac mismatch at row %d: stored=%s recomputed=%s",
+				i+1, claimed, recomputed)
+		}
+		prev = claimed
+		count = i + 1
+	}
+	chainTip = prev
+	return count, chainTip, nil
+}
+
+// LoadKeyFile reads a signing key file. Refuses keys shorter than 32
+// bytes (matches Rust: 2026-05-03 kimi BLOCK fix lifted the minimum
+// from 16 to 32 to align with HMAC-SHA256 best practice).
+func LoadKeyFile(path string) ([]byte, error) {
+	key, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("read key file %s: %w", path, err)
+	}
+	if len(key) < 32 {
+		return nil, fmt.Errorf("signing key is %d bytes; recommend ≥32 bytes for HMAC-SHA256", len(key))
+	}
+	return key, nil
+}

internal/catalogd/subject_test.go

@@ -0,0 +1,364 @@
+package catalogd
+
+import (
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+)
+
+// deterministicKey is the same fixture key the Rust tests use:
+// (0u8..32).collect() — so a Rust-written chain verifies under Go.
+func deterministicKey() []byte {
+	k := make([]byte, 32)
+	for i := range k {
+		k[i] = byte(i)
+	}
+	return k
+}
+
+func mkRow(candidateID string, fields []string, prevHash, ts string) SubjectAuditRow {
+	t, _ := time.Parse(time.RFC3339Nano, ts)
+	return SubjectAuditRow{
+		Schema:      "subject_audit.v1",
+		Ts:          t,
+		CandidateID: candidateID,
+		Accessor: AuditAccessor{
+			Kind:    "gateway_lookup",
+			Daemon:  "gateway",
+			Purpose: "fill_validation",
+			TraceID: "",
+		},
+		FieldsAccessed: fields,
+		Result:         "success",
+		PrevChainHash:  prevHash,
+		RowHmac:        "", // computed below
+	}
+}
+
+// TestCanonicalJSON_KeysSortedAlphabetically asserts the same property
+// the Rust unit test asserts (subject_audit::tests::canonical_json_sorts_keys_alphabetically).
+func TestCanonicalJSON_KeysSortedAlphabetically(t *testing.T) {
+	v := map[string]any{
+		"z": 1,
+		"a": 2,
+		"m": map[string]any{"y": 1, "b": 2},
+	}
+	var buf strings.Builder
+	if err := writeCanonical(&buf, v); err != nil {
+		t.Fatalf("canonical: %v", err)
+	}
+	s := buf.String()
+	a, m, z := strings.Index(s, "\"a\""), strings.Index(s, "\"m\""), strings.Index(s, "\"z\"")
+	if !(a < m && m < z) {
+		t.Fatalf("top-level keys out of order: %s", s)
+	}
+	b, y := strings.Index(s, "\"b\""), strings.Index(s, "\"y\"")
+	if !(b < y) {
+		t.Fatalf("nested keys out of order: %s", s)
+	}
+}
+
+// TestCanonicalJSON_ArraysPreserveOrder asserts arrays are NOT sorted —
+// matches Rust subject_audit::tests::canonical_json_arrays_preserve_order.
+func TestCanonicalJSON_ArraysPreserveOrder(t *testing.T) {
+	v := map[string]any{"k": []any{"c", "a", "b"}}
+	var buf strings.Builder
+	if err := writeCanonical(&buf, v); err != nil {
+		t.Fatalf("canonical: %v", err)
+	}
+	if !strings.Contains(buf.String(), "\"c\",\"a\",\"b\"") {
+		t.Fatalf("array order altered: %s", buf.String())
+	}
+}
+
+// buildEntry produces an AuditLogEntry by computing the HMAC against
+// the row's struct-derived canonical bytes, then storing the resulting
+// row JSON as the raw bytes. Test-only — production reads raw bytes
+// straight from disk so the time-precision drift doesn't apply.
+func buildEntry(row SubjectAuditRow, key []byte, prev string) AuditLogEntry {
+	canon, err := canonicalRowBytesFromStruct(&row)
+	if err != nil {
+		panic(err)
+	}
+	row.RowHmac = computeRowHMAC(key, prev, canon)
+	raw, err := json.Marshal(row)
+	if err != nil {
+		panic(err)
+	}
+	return AuditLogEntry{Row: row, Raw: raw}
+}
+
+// TestVerifyChain_ReplaysAndReachesTip writes 3 rows with HMACs computed
+// the same way Rust would, then verifies they chain. This is the local
+// half of the parity contract — the cross-runtime half (Rust writes,
+// Go verifies) is covered by scripts/cutover/parity/subject_audit_parity.sh.
+func TestVerifyChain_ReplaysAndReachesTip(t *testing.T) {
+	key := deterministicKey()
+	r1 := mkRow("CAND-PARITY", []string{"name"}, GenesisHash, "2026-05-03T12:00:00Z")
+	e1 := buildEntry(r1, key, GenesisHash)
+	r2 := mkRow("CAND-PARITY", []string{"phone"}, e1.Row.RowHmac, "2026-05-03T12:00:01Z")
+	e2 := buildEntry(r2, key, e1.Row.RowHmac)
+	r3 := mkRow("CAND-PARITY", []string{"email"}, e2.Row.RowHmac, "2026-05-03T12:00:02Z")
+	e3 := buildEntry(r3, key, e2.Row.RowHmac)
+
+	count, tip, err := VerifyChain([]AuditLogEntry{e1, e2, e3}, key)
+	if err != nil {
+		t.Fatalf("verify failed: %v", err)
+	}
+	if count != 3 {
+		t.Fatalf("expected 3 rows verified, got %d", count)
+	}
+	if tip != e3.Row.RowHmac {
+		t.Fatalf("chain tip wrong: tip=%s expected=%s", tip, e3.Row.RowHmac)
+	}
+}
+
+// TestVerifyChain_EmptyLogIsTriviallyValid mirrors Rust's empty-log
+// special case: 0 rows, GENESIS tip, no error.
+func TestVerifyChain_EmptyLogIsTriviallyValid(t *testing.T) {
+	count, tip, err := VerifyChain(nil, deterministicKey())
+	if err != nil {
+		t.Fatalf("empty log returned error: %v", err)
+	}
+	if count != 0 {
+		t.Fatalf("expected 0 rows on empty log, got %d", count)
+	}
+	if tip != GenesisHash {
+		t.Fatalf("expected GENESIS tip on empty log, got %q", tip)
+	}
+}
+
+// TestVerifyChain_TamperDetected: tamper the raw line's `result` field
+// (the canonicalizer sees the new bytes; HMAC mismatches the stored hash).
+func TestVerifyChain_TamperDetected(t *testing.T) {
+	key := deterministicKey()
+	r1 := mkRow("CAND-T", []string{"name"}, GenesisHash, "2026-05-03T12:00:00Z")
+	e1 := buildEntry(r1, key, GenesisHash)
+	// Tamper: replace "success" with "denied" in the raw bytes ONLY.
+	// The struct's row_hmac (used as the "stored" comparator) stays put.
+	e1.Raw = []byte(strings.Replace(string(e1.Raw), `"success"`, `"denied"`, 1))
+	_, _, err := VerifyChain([]AuditLogEntry{e1}, key)
+	if err == nil {
+		t.Fatal("expected hmac mismatch after tamper, got nil")
+	}
+	if !strings.Contains(err.Error(), "hmac mismatch") {
+		t.Fatalf("expected hmac mismatch, got: %v", err)
+	}
+}
+
+// TestVerifyChain_BadKeyRejectsValidRows: same rows + wrong key = mismatch.
+func TestVerifyChain_BadKeyRejectsValidRows(t *testing.T) {
+	good := deterministicKey()
+	r1 := mkRow("CAND-BK", []string{"name"}, GenesisHash, "2026-05-03T12:00:00Z")
+	e1 := buildEntry(r1, good, GenesisHash)
+	bad := make([]byte, 32)
+	for i := range bad {
+		bad[i] = 0xff
+	}
+	_, _, err := VerifyChain([]AuditLogEntry{e1}, bad)
+	if err == nil {
+		t.Fatal("expected hmac mismatch with wrong key")
+	}
+}
+
+// TestComputeRowHMAC_StableAcrossRuns: same row + same key always = same hash.
+func TestComputeRowHMAC_StableAcrossRuns(t *testing.T) {
+	key := deterministicKey()
+	r := mkRow("CAND-S", []string{"a", "b"}, GenesisHash, "2026-05-03T12:00:00Z")
+	c1, _ := canonicalRowBytesFromStruct(&r)
+	c2, _ := canonicalRowBytesFromStruct(&r)
+	if string(c1) != string(c2) {
+		t.Fatalf("canonical bytes unstable across runs:\n  c1=%s\n  c2=%s", c1, c2)
+	}
+	h1 := computeRowHMAC(key, GenesisHash, c1)
+	h2 := computeRowHMAC(key, GenesisHash, c2)
+	if h1 != h2 {
+		t.Fatalf("hmac unstable across runs: %s vs %s", h1, h2)
+	}
+	if len(h1) != 64 {
+		t.Fatalf("hmac wrong length %d", len(h1))
+	}
+	// Sanity: hex-decodable.
+	if _, err := hex.DecodeString(h1); err != nil {
+		t.Fatalf("hmac not hex: %v", err)
+	}
+}
+
+// TestKnownAnswerVector matches a Go-computed reference. The same
+// inputs must produce this exact byte string under Rust as well —
+// scripts/cutover/parity/subject_audit_parity.sh runs the Rust helper
+// against this exact fixture and asserts byte-identical output.
+//
+// If you change the fixture, rebuild Rust's parity_subject_audit + Go's
+// helper and update both sides together.
+func TestKnownAnswerVector(t *testing.T) {
+	key := deterministicKey()
+	r := SubjectAuditRow{
+		Schema:      "subject_audit.v1",
+		Ts:          time.Date(2026, 5, 3, 12, 0, 0, 0, time.UTC),
+		CandidateID: "WORKER-FIXED",
+		Accessor: AuditAccessor{
+			Kind:    "gateway_lookup",
+			Daemon:  "gateway",
+			Purpose: "parity_test",
+			TraceID: "trace-fixed",
+		},
+		FieldsAccessed: []string{"name"},
+		Result:         "success",
+		PrevChainHash:  GenesisHash,
+		RowHmac:        "",
+	}
+	canon, err := canonicalRowBytesFromStruct(&r)
+	if err != nil {
+		t.Fatalf("canonical: %v", err)
+	}
+	t.Logf("canonical bytes: %s", canon)
+	hmacHex := computeRowHMAC(key, GenesisHash, canon)
+	t.Logf("hmac: %s", hmacHex)
+	// Sanity: round-trip through encoding/json + canonicalization is stable.
+	again, err := canonicalRowBytesFromStruct(&r)
+	if err != nil {
+		t.Fatalf("canonical 2: %v", err)
+	}
+	if string(canon) != string(again) {
+		t.Fatalf("canonical drift: %s vs %s", canon, again)
+	}
+	// Sanity: real HMAC against the canonical bytes.
+	mac := hmac.New(sha256.New, key)
+	mac.Write([]byte(GenesisHash))
+	mac.Write(canon)
+	expected := hex.EncodeToString(mac.Sum(nil))
+	if hmacHex != expected {
+		t.Fatalf("computeRowHMAC drift: %s vs %s", hmacHex, expected)
+	}
+}
+
+// TestVerifyChain_HtmlChars_NotEscaped is the regression test for the
+// 2026-05-03 opus scrum WARN: Go's json.Marshal escapes `<`, `>`, `&`
+// to `<`, `>`, `&` by default; Rust's serde_json keeps
+// them literal. Audit rows with these chars in any string field would
+// silently break the chain across runtimes. Fix is in writeCanonical's
+// marshalNoEscapeHTML helper. This test asserts canonical bytes contain
+// the literal `<`, `>`, `&` (proving the fix is in place).
+func TestVerifyChain_HtmlChars_NotEscaped(t *testing.T) {
+	r := mkRow("CAND-HTML", []string{"name"}, GenesisHash, "2026-05-03T12:00:00Z")
+	r.Accessor.Purpose = "error & retry"   // & must NOT be &
+	r.Accessor.TraceID = "<HTTP-Req-Id>"   // < and > must NOT be < / >
+	canon, err := canonicalRowBytesFromStruct(&r)
+	if err != nil {
+		t.Fatalf("canonical: %v", err)
+	}
+	s := string(canon)
+	// FAIL if the bytes contain Go's HTML-safe < / > / &
+	// escape sequences (six raw chars each: backslash, u, 0, 0, hex, hex).
+	// Those wouldn't match Rust's literal-char output and would silently
+	// break the cross-runtime HMAC chain. Note: the strings below are
+	// raw-string literals — the backslash + u006xx is six literal bytes,
+	// NOT a Go-source unicode escape.
+	if strings.Contains(s, "\\u003c") || strings.Contains(s, "\\u003e") || strings.Contains(s, "\\u0026") {
+		t.Fatalf("canonical bytes contain Go HTML-escape sequences (would diverge from Rust):\n%s", s)
+	}
+	// PASS only if the literal chars survived round-trip.
+	if !strings.Contains(s, "\"<HTTP-Req-Id>\"") || !strings.Contains(s, "\"error & retry\"") {
+		t.Fatalf("canonical bytes missing literal <>&:\n%s", s)
+	}
+}
+
+// TestVerifyChain_RawBytesPreserveTimePrecision is the regression test
+// for the 2026-05-03 WORKER-5 finding: when a row's nanoseconds end in
+// 0, time.RFC3339Nano strips the trailing zero on re-marshal, producing
+// different canonical bytes than Rust's chrono AutoSi (which always
+// emits 9 digits). VerifyChain MUST canonicalize from the raw line
+// bytes to avoid this drift. Test feeds a hand-crafted raw line whose
+// ts has a trailing-zero nano value and asserts verify succeeds when
+// the chain hash was computed against THOSE EXACT bytes.
+func TestVerifyChain_RawBytesPreserveTimePrecision(t *testing.T) {
+	key := deterministicKey()
+	// Hand-crafted raw line exactly as Rust would write it, with
+	// nanoseconds=461439210 (trailing zero present).
+	rawNoHmac := `{"schema":"subject_audit.v1","ts":"2026-05-03T09:12:47.461439210Z","candidate_id":"WORKER-5","accessor":{"kind":"validator_lookup","daemon":"gateway","purpose":"validator_worker_lookup","trace_id":""},"fields_accessed":["exists"],"result":"not_found","prev_chain_hash":"GENESIS"}`
+	canonical, err := canonicalRowBytesFromRaw([]byte(rawNoHmac))
+	if err != nil {
+		t.Fatalf("canonicalize raw: %v", err)
+	}
+	hmacHex := computeRowHMAC(key, GenesisHash, canonical)
+	// Compose the full row by injecting row_hmac at the end (matches
+	// what the Rust writer produces — declaration order + appended hmac).
+	rawFull := strings.TrimSuffix(rawNoHmac, "}") + `,"row_hmac":"` + hmacHex + `"}`
+
+	var row SubjectAuditRow
+	if err := json.Unmarshal([]byte(rawFull), &row); err != nil {
+		t.Fatalf("unmarshal: %v", err)
+	}
+	entry := AuditLogEntry{Row: row, Raw: []byte(rawFull)}
+	count, tip, err := VerifyChain([]AuditLogEntry{entry}, key)
+	if err != nil {
+		t.Fatalf("verify failed (regression: time-precision drift): %v", err)
+	}
+	if count != 1 {
+		t.Fatalf("expected 1 row verified, got %d", count)
+	}
+	if tip != hmacHex {
+		t.Fatalf("tip mismatch: %s vs %s", tip, hmacHex)
+	}
+}
+
+// TestSubjectManifest_RoundTripJSON: parse a fixture JSON identical in
+// shape to what crates/catalogd/src/registry.rs::put_subject writes to
+// data/_catalog/subjects/<id>.json. If this fails, the Go reader is
+// out of sync with the Rust writer (a Step 8 contract violation).
+func TestSubjectManifest_RoundTripJSON(t *testing.T) {
+	src := `{
+  "schema": "subject_manifest.v1",
+  "candidate_id": "WORKER-1",
+  "created_at": "2026-05-03T08:22:24.571647177Z",
+  "updated_at": "2026-05-03T08:22:24.571647177Z",
+  "status": "active",
+  "vertical": "unknown",
+  "consent": {
+    "general_pii": {
+      "status": "pending_backfill_review",
+      "version": ""
+    },
+    "biometric": {
+      "status": "never_collected"
+    }
+  },
+  "retention": {
+    "general_pii_until": "2030-05-02T08:22:24.571647177Z",
+    "policy": "4_year_default"
+  },
+  "datasets": [
+    {"name": "workers_500k", "key_column": "worker_id", "key_value": "1"}
+  ],
+  "safe_views": ["workers_safe"],
+  "audit_log_path": "_catalog/subjects/WORKER-1.audit.jsonl",
+  "audit_log_chain_root": ""
+}`
+	var m SubjectManifest
+	if err := json.Unmarshal([]byte(src), &m); err != nil {
+		t.Fatalf("unmarshal: %v", err)
+	}
+	if m.CandidateID != "WORKER-1" {
+		t.Fatalf("candidate_id wrong: %s", m.CandidateID)
+	}
+	if m.Status != "active" {
+		t.Fatalf("status wrong: %s", m.Status)
+	}
+	if m.Consent.GeneralPii.Status != "pending_backfill_review" {
+		t.Fatalf("general_pii.status wrong: %s", m.Consent.GeneralPii.Status)
+	}
+	if m.Consent.Biometric.Status != "never_collected" {
+		t.Fatalf("biometric.status wrong: %s", m.Consent.Biometric.Status)
+	}
+	if m.Retention.Policy != "4_year_default" {
+		t.Fatalf("retention.policy wrong: %s", m.Retention.Policy)
+	}
+	if len(m.Datasets) != 1 || m.Datasets[0].Name != "workers_500k" {
+		t.Fatalf("datasets wrong: %+v", m.Datasets)
+	}
+}

internal/distillation/types.go

@@ -125,9 +125,15 @@ const (
 // Provenance is the source-linkage every distillation record carries.
 // SourceFile is required (no record without source linkage); other
 // fields are best-effort for de-duplication and trace-back.
+//
+// LineOffset is intentionally NOT `omitempty`: line offset 0 is the
+// first row of a source file — a real, semantically-meaningful value.
+// Stripping it on first-row records would silently diverge from the
+// Bun materializer (which always emits the field). Surfaced by the
+// 2026-05-02 cross-runtime parity probe.
 type Provenance struct {
 	SourceFile string `json:"source_file"`
-	LineOffset  int64  `json:"line_offset,omitempty"`
+	LineOffset int64  `json:"line_offset"`
 	SigHash    string `json:"sig_hash"`
 	RecordedAt string `json:"recorded_at"` // ISO 8601
 }

internal/shared/config.go

@@ -165,6 +165,12 @@ type ValidatordConfig struct {
 	DefaultMaxTokens int `toml:"default_max_tokens"`
 	// Per-call timeout for the chat hop in seconds. 0 = 240s.
 	ChatTimeoutSecs int `toml:"chat_timeout_secs"`
+	// SessionLogPath: where to append SessionRecord JSONL rows for
+	// offline analysis (DuckDB queries, scrum review tooling). Empty
+	// = disabled. Production sets a stable path under
+	// /var/lib/lakehouse/validator/sessions.jsonl. Append-only,
+	// best-effort; see internal/validator/session_log.go.
+	SessionLogPath string `toml:"session_log_path"`
 }
 
 // ObserverdConfig drives the observer service (cmd/observerd).
@@ -240,6 +246,13 @@ type LogConfig struct {
 // the corpus-downgrade rule: it's already weak, no need to downgrade
 // further. Strong (paid / cloud / frontier) models trigger the gate.
 type ModelsConfig struct {
+	// ⚠ UNWIRED scaffolding — these tier fields parse from TOML and
+	// Resolve() reads them, but as of 2026-05-03 NO OTHER CODE calls
+	// Resolve(). Setting these in lakehouse.toml has no runtime effect
+	// on routing. Customer hot path uses local Ollama via direct model
+	// name per PRD line 70 (everything runs locally). If you wire up
+	// Resolve() consumers, document them here so the next person knows
+	// the field is live, not dead scaffolding.
 	LocalFast      string `toml:"local_fast"`
 	LocalEmbed     string `toml:"local_embed"`
 	LocalJudge     string `toml:"local_judge"`
@@ -254,6 +267,9 @@ type ModelsConfig struct {
 	FrontierStrong string `toml:"frontier_strong"`
 	FrontierFree   string `toml:"frontier_free"`
 
+	// WeakModels IS live — internal/workflow/modes.go reads it at
+	// startup, internal/matrix/downgrade.go uses the list for the
+	// strong-model auto-downgrade gate. Don't lump with unwired fields.
 	WeakModels []string `toml:"weak_models"`
 }
 
@@ -393,6 +409,7 @@ func DefaultConfig() Config {
 			DefaultMaxIterations: 3,
 			DefaultMaxTokens:     4096,
 			ChatTimeoutSecs:      240,
+			SessionLogPath:       "", // empty = no session JSONL. Operators set under /var/lib/lakehouse/validator/sessions.jsonl.
 		},
 		Chatd: ChatdConfig{
 			Bind:               "127.0.0.1:3220",

internal/shared/langfuse_middleware.go

@@ -1,6 +1,7 @@
 package shared
 
 import (
+	"context"
 	"net/http"
 	"os"
 	"time"
@@ -8,6 +9,30 @@ import (
 	"git.agentview.dev/profit/golangLAKEHOUSE/internal/langfuse"
 )
 
+// TraceIDHeader propagates a Langfuse trace id across services. When
+// validatord makes a /v1/iterate call that internally calls chatd's
+// /v1/chat, validatord sends this header so both daemons' middleware
+// emit spans under the SAME trace tree (rather than two unrelated
+// traces). Closes the multi-call observability gap J flagged
+// 2026-05-02 ("we need to make sure they have the corpus of
+// information to complete the process and we want to spot errors").
+const TraceIDHeader = "X-Lakehouse-Trace-Id"
+
+// traceIDCtxKey is the context value key for the per-request trace id.
+// Handlers downstream of langfuseMiddleware can pull it via TraceIDFromCtx
+// to attach child spans (e.g. iteration-attempt spans inside validatord).
+type traceIDCtxKey struct{}
+
+// TraceIDFromCtx returns the per-request Langfuse trace id, or "" if
+// the middleware didn't set one (Langfuse not configured / /health
+// bypass / no Client wired).
+func TraceIDFromCtx(ctx context.Context) string {
+	if v, ok := ctx.Value(traceIDCtxKey{}).(string); ok {
+		return v
+	}
+	return ""
+}
+
 // langfuseMiddleware emits one Langfuse trace per HTTP request, with
 // a single span carrying start/end timestamps + status code. Per
 // OPEN item #2 (closed by the wave that adds this file): production
@@ -36,7 +61,14 @@ func langfuseMiddleware(serviceName string, lf *langfuse.Client) func(http.Handl
 			start := time.Now()
 			sw := &statusWriter{ResponseWriter: w, status: http.StatusOK}
 
-			traceID := lf.Trace(r.Context(), langfuse.TraceInput{
+			// If the caller forwarded a trace id (cross-service parent
+			// linkage) reuse it instead of starting a new trace. Spans
+			// from this service then attach to the parent trace tree
+			// so an /v1/iterate session shows as one trace with
+			// children for each /v1/chat hop.
+			traceID := r.Header.Get(TraceIDHeader)
+			if traceID == "" {
+				traceID = lf.Trace(r.Context(), langfuse.TraceInput{
 					Name: serviceName + " " + r.Method + " " + r.URL.Path,
 					Tags: []string{serviceName, r.Method},
 					Metadata: map[string]any{
@@ -45,6 +77,12 @@ func langfuseMiddleware(serviceName string, lf *langfuse.Client) func(http.Handl
 						"remote_addr": r.RemoteAddr,
 					},
 				})
+			}
+
+			// Stash the trace id on the request context so downstream
+			// handlers can attach finer-grained spans (e.g. one per
+			// iteration attempt inside validator.Iterate).
+			r = r.WithContext(context.WithValue(r.Context(), traceIDCtxKey{}, traceID))
 
 			next.ServeHTTP(sw, r)
 
@@ -89,13 +127,18 @@ func (sw *statusWriter) WriteHeader(code int) {
 	sw.ResponseWriter.WriteHeader(code)
 }
 
-// loadLangfuseFromEnv builds a langfuse.Client from environment
+// LoadLangfuseFromEnv builds a langfuse.Client from environment
 // variables. Returns nil if any of LANGFUSE_URL / LANGFUSE_PUBLIC_KEY
 // / LANGFUSE_SECRET_KEY is unset (best-effort: missing config means
 // no tracing, never a startup error). Same env names as the bare
 // /etc/lakehouse/langfuse.env file used by the multi_coord_stress
 // driver — operators ship one env file across every daemon.
-func loadLangfuseFromEnv() *langfuse.Client {
+//
+// Exported 2026-05-02 so daemons that need to emit application-level
+// child spans (validatord's iterate-attempt spans) can hold their own
+// reference to the same client `shared.Run` is already wiring into
+// the middleware.
+func LoadLangfuseFromEnv() *langfuse.Client {
 	url := os.Getenv("LANGFUSE_URL")
 	pk := os.Getenv("LANGFUSE_PUBLIC_KEY")
 	sk := os.Getenv("LANGFUSE_SECRET_KEY")

internal/shared/langfuse_middleware_test.go

@@ -119,6 +119,50 @@ func TestLangfuseMiddleware_RealRequestEmitted(t *testing.T) {
 	}
 }
 
+// TestLangfuseMiddleware_HonorsTraceIDHeader locks the cross-service
+// trace-linkage contract: when validatord forwards a /v1/iterate's
+// trace id to chatd via X-Lakehouse-Trace-Id, chatd's middleware
+// MUST reuse that id rather than minting a new one. Without this,
+// every chat hop spawned its own orphan trace and an iterate session
+// with N retries showed in Langfuse as N+1 disconnected traces.
+//
+// We verify by inspecting the trace id stashed on the request
+// context — handlers downstream pull it via TraceIDFromCtx and
+// attach finer-grained spans to it.
+func TestLangfuseMiddleware_HonorsTraceIDHeader(t *testing.T) {
+	// nil client path is fine — TraceIDFromCtx still propagates the
+	// header value because the middleware sets the ctx value before
+	// minting any new id. But that's only true when the client is
+	// non-nil (the nil-client branch is a passthrough that never sets
+	// the ctx value). So we wire a real (mocked) Langfuse to exercise
+	// the header-honoring branch.
+	lfMock := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = io.ReadAll(r.Body)
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer lfMock.Close()
+	lf := langfuse.New(lfMock.URL, "test-pk", "test-sk", nil)
+
+	mw := langfuseMiddleware("test-service", lf)
+	var observed string
+	h := mw(http.HandlerFunc(func(_ http.ResponseWriter, r *http.Request) {
+		observed = TraceIDFromCtx(r.Context())
+	}))
+	srv := httptest.NewServer(h)
+	defer srv.Close()
+
+	req, _ := http.NewRequest("POST", srv.URL+"/api/echo", nil)
+	req.Header.Set(TraceIDHeader, "trace-from-parent")
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("POST: %v", err)
+	}
+	resp.Body.Close()
+	if observed != "trace-from-parent" {
+		t.Errorf("expected forwarded trace id, got %q", observed)
+	}
+}
+
 // TestLangfuseMiddleware_StatusCaptured locks the status-writer
 // wrapping: when the handler returns 500, the middleware must see
 // 500 in the span output (otherwise error traces all show 200 and

internal/shared/server.go

@@ -80,7 +80,7 @@ func Run(serviceName, addr string, register RegisterRoutes, auth AuthConfig) err
 	// gets free production-traffic trace visibility when those env
 	// vars are set. Missing any of the three → nil client → middleware
 	// becomes a passthrough.
-	lf := loadLangfuseFromEnv()
+	lf := LoadLangfuseFromEnv()
 	if lf != nil {
 		// Make sure pending events flush on graceful shutdown so the
 		// last few requests' traces don't get lost.

internal/validator/iterate.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"strings"
+	"time"
 )
 
 // IterateRequest is the input to Iterate. Mirrors Rust's
@@ -20,14 +21,24 @@ type IterateRequest struct {
 	MaxIterations int            `json:"max_iterations,omitempty"`
 	Temperature   *float64       `json:"temperature,omitempty"`
 	MaxTokens     int            `json:"max_tokens,omitempty"`
+	// TraceID lets external schedulers force a parent trace id (so the
+	// iterate session lands as a child of an upstream Langfuse trace).
+	// Empty = the caller didn't provide one; validatord may still
+	// generate one from request context.
+	TraceID string `json:"trace_id,omitempty"`
 }
 
 // IterateAttempt is one row in the history. raw is capped at 2000
-// chars on the wire to keep responses bounded.
+// chars on the wire to keep responses bounded. SpanID points at the
+// Langfuse span emitted for this attempt (if a Tracer was wired in
+// IterateConfig); empty when tracing was disabled. Operators reading
+// `data/_kb/replay_runs.jsonl` or staffing-co-pilot session logs can
+// jump from a row to its full trace tree via this id.
 type IterateAttempt struct {
 	Iteration int           `json:"iteration"`
 	Raw       string        `json:"raw"`
 	Status    AttemptStatus `json:"status"`
+	SpanID    string        `json:"span_id,omitempty"`
 }
 
 // AttemptStatus is the per-attempt verdict. Tagged JSON so consumers
@@ -38,11 +49,14 @@ type AttemptStatus struct {
 }
 
 // IterateResponse is the success payload (200 + Report + accepted artifact).
+// TraceID echoes back the parent trace id so callers can pivot to
+// Langfuse and see the full session (chat hops + validator verdicts).
 type IterateResponse struct {
 	Artifact   map[string]any   `json:"artifact"`
 	Validation Report           `json:"validation"`
 	Iterations int              `json:"iterations"`
 	History    []IterateAttempt `json:"history"`
+	TraceID    string           `json:"trace_id,omitempty"`
 }
 
 // IterateFailure is the max-iter-exhausted payload (422 + history).
@@ -50,19 +64,53 @@ type IterateFailure struct {
 	Error      string           `json:"error"`
 	Iterations int              `json:"iterations"`
 	History    []IterateAttempt `json:"history"`
+	TraceID    string           `json:"trace_id,omitempty"`
 }
 
 // ChatCaller is the seam Iterate uses to invoke an LLM. Tests inject
 // scripted callers; production wires this to the chatd /v1/chat HTTP
 // endpoint. Implementations must return the model's textual content
-// (no choices wrapper, no message envelope).
-type ChatCaller func(ctx context.Context, system, user, provider, model string, temperature *float64, maxTokens int) (string, error)
+// (no choices wrapper, no message envelope). traceID is the Langfuse
+// parent trace id — HTTP transports forward it as the
+// `X-Lakehouse-Trace-Id` header so chatd's middleware attaches its
+// spans to the same trace.
+type ChatCaller func(ctx context.Context, system, user, provider, model string, temperature *float64, maxTokens int, traceID string) (string, error)
+
+// AttemptSpan describes one iteration's chat-call + validator-verdict.
+// The Tracer (see IterateConfig) consumes these to emit Langfuse
+// spans — one span per attempt, plus inputs/outputs so an operator
+// scrolling Langfuse sees the full prompt → raw → verdict chain
+// without having to join multiple JSONL files.
+type AttemptSpan struct {
+	TraceID    string
+	ParentID   string // span id of the surrounding /v1/iterate http request, if any
+	Iteration  int
+	Model      string
+	Provider   string
+	Prompt     string
+	Raw        string
+	Verdict    AttemptStatus
+	StartTime  time.Time
+	EndTime    time.Time
+}
+
+// Tracer is the hook Iterate calls after each attempt. Returns the
+// span id so it lands in IterateAttempt.SpanID. nil = tracing
+// disabled (tests, or production with Langfuse unconfigured).
+//
+// Production wiring lives in cmd/validatord/main.go and routes to
+// internal/langfuse.Client — kept as an interface here so the
+// validator package doesn't depend on langfuse for unit tests.
+type Tracer func(span AttemptSpan) string
 
 // IterateConfig threads daemon-level settings into the orchestrator.
 type IterateConfig struct {
 	DefaultMaxIterations int
 	DefaultMaxTokens     int
 	DefaultTemperature   float64
+	// Tracer (optional) emits one span per iteration attempt for
+	// per-call visibility. nil = no tracing.
+	Tracer Tracer
 }
 
 const (
@@ -101,36 +149,59 @@ func Iterate(ctx context.Context, req IterateRequest, cfg IterateConfig, chat Ch
 
 	currentPrompt := req.Prompt
 	history := make([]IterateAttempt, 0, maxIter)
+	traceID := req.TraceID
+
+	// recordAttempt: append to history, emit a Langfuse span if a
+	// Tracer is wired, return the SpanID. Centralized so every code
+	// path (no_json, accepted, validation_failed) hits the same
+	// observability path — no easy way to forget tracing on a branch.
+	recordAttempt := func(iteration int, raw string, verdict AttemptStatus, started time.Time) string {
+		spanID := ""
+		if cfg.Tracer != nil && traceID != "" {
+			spanID = cfg.Tracer(AttemptSpan{
+				TraceID:   traceID,
+				Iteration: iteration,
+				Model:     req.Model,
+				Provider:  req.Provider,
+				Prompt:    currentPrompt,
+				Raw:       raw,
+				Verdict:   verdict,
+				StartTime: started,
+				EndTime:   time.Now(),
+			})
+		}
+		history = append(history, IterateAttempt{
+			Iteration: iteration,
+			Raw:       trim(raw, 2000),
+			Status:    verdict,
+			SpanID:    spanID,
+		})
+		return spanID
+	}
 
 	for i := 0; i < maxIter; i++ {
-		raw, err := chat(ctx, req.System, currentPrompt, req.Provider, req.Model, temp, maxTokens)
+		started := time.Now()
+		raw, err := chat(ctx, req.System, currentPrompt, req.Provider, req.Model, temp, maxTokens, traceID)
 		if err != nil {
 			return nil, nil, fmt.Errorf("/v1/chat hop failed at iter %d: %w", i, err)
 		}
 
 		artifact := ExtractJSON(raw)
 		if artifact == nil {
-			history = append(history, IterateAttempt{
-				Iteration: i,
-				Raw:       trim(raw, 2000),
-				Status:    AttemptStatus{Kind: "no_json"},
-			})
+			recordAttempt(i, raw, AttemptStatus{Kind: "no_json"}, started)
 			currentPrompt = req.Prompt + "\n\nYour previous attempt did not contain a JSON object. Reply with ONLY a valid JSON object matching the requested artifact shape."
 			continue
 		}
 
 		report, vErr := validate(req.Kind, artifact)
 		if vErr == nil {
-			history = append(history, IterateAttempt{
-				Iteration: i,
-				Raw:       trim(raw, 2000),
-				Status:    AttemptStatus{Kind: "accepted"},
-			})
+			recordAttempt(i, raw, AttemptStatus{Kind: "accepted"}, started)
 			return &IterateResponse{
 				Artifact:   artifact,
 				Validation: report,
 				Iterations: i + 1,
 				History:    history,
+				TraceID:    traceID,
 			}, nil, nil
 		}
 
@@ -138,11 +209,7 @@ func Iterate(ctx context.Context, req IterateRequest, cfg IterateConfig, chat Ch
 		// The model sees concrete failure mode + retries with corrective
 		// context. Same "validator IS the observer" shape as Phase 43.
 		errSummary := vErr.Error()
-		history = append(history, IterateAttempt{
-			Iteration: i,
-			Raw:       trim(raw, 2000),
-			Status:    AttemptStatus{Kind: "validation_failed", Error: errSummary},
-		})
+		recordAttempt(i, raw, AttemptStatus{Kind: "validation_failed", Error: errSummary}, started)
 		currentPrompt = req.Prompt + "\n\nPrior attempt failed validation:\n" + errSummary + "\n\nFix the specific issue above and respond with a corrected JSON object."
 	}
 
@@ -150,6 +217,7 @@ func Iterate(ctx context.Context, req IterateRequest, cfg IterateConfig, chat Ch
 		Error:      fmt.Sprintf("max iterations reached (%d) without passing validation", maxIter),
 		Iterations: maxIter,
 		History:    history,
+		TraceID:    traceID,
 	}, nil
 }
 

internal/validator/iterate_test.go

@@ -3,6 +3,7 @@ package validator
 import (
 	"context"
 	"errors"
+	"fmt"
 	"testing"
 )
 
@@ -69,7 +70,7 @@ func TestExtractJSON_TopLevelArrayReturnsFirstInnerObject(t *testing.T) {
 
 func scriptedChat(responses ...string) (ChatCaller, *int) {
 	idx := 0
-	return func(_ context.Context, _, _ string, _, _ string, _ *float64, _ int) (string, error) {
+	return func(_ context.Context, _, _ string, _, _ string, _ *float64, _ int, _ string) (string, error) {
 		if idx >= len(responses) {
 			return "", errors.New("scripted chat exhausted")
 		}
@@ -175,8 +176,96 @@ func TestIterate_MaxIterationsExhaustedReturnsFailure(t *testing.T) {
 	}
 }
 
+// TestIterate_TracerEmitsSpanPerAttempt locks the per-attempt
+// observability contract: when a Tracer is wired AND a TraceID is
+// present, every retry produces exactly one span and the SpanID
+// lands on the IterateAttempt history row.
+func TestIterate_TracerEmitsSpanPerAttempt(t *testing.T) {
+	chat, _ := scriptedChat(
+		"no json",
+		`{"k":"v"}`,
+	)
+	validate := func(_ string, _ map[string]any) (Report, error) { return Report{}, nil }
+
+	var spans []AttemptSpan
+	tracer := func(s AttemptSpan) string {
+		spans = append(spans, s)
+		return fmt.Sprintf("span-%d", s.Iteration)
+	}
+
+	resp, _, err := Iterate(context.Background(),
+		IterateRequest{Kind: "playbook", Prompt: "X", Provider: "ollama", Model: "qwen", TraceID: "trace-abc"},
+		IterateConfig{Tracer: tracer}, chat, validate)
+	if err != nil {
+		t.Fatalf("Iterate: %v", err)
+	}
+	if resp.TraceID != "trace-abc" {
+		t.Errorf("TraceID echo: got %q, want trace-abc", resp.TraceID)
+	}
+	if len(spans) != 2 {
+		t.Fatalf("expected 2 emitted spans, got %d", len(spans))
+	}
+	if spans[0].Verdict.Kind != "no_json" || spans[1].Verdict.Kind != "accepted" {
+		t.Errorf("verdict propagation: %+v", spans)
+	}
+	if resp.History[0].SpanID != "span-0" || resp.History[1].SpanID != "span-1" {
+		t.Errorf("SpanID stamping: %+v", resp.History)
+	}
+	if spans[0].TraceID != "trace-abc" {
+		t.Errorf("TraceID didn't reach the tracer: %q", spans[0].TraceID)
+	}
+}
+
+// TestIterate_NoTraceIDSkipsTracer guards the "Langfuse not configured"
+// path: tracer is non-nil but trace_id is empty → we MUST NOT emit
+// orphan spans.
+func TestIterate_NoTraceIDSkipsTracer(t *testing.T) {
+	chat, _ := scriptedChat(`{"k":"v"}`)
+	validate := func(_ string, _ map[string]any) (Report, error) { return Report{}, nil }
+	called := 0
+	tracer := func(_ AttemptSpan) string {
+		called++
+		return "should-not-be-used"
+	}
+	resp, _, err := Iterate(context.Background(),
+		IterateRequest{Kind: "playbook", Prompt: "X", Provider: "ollama", Model: "qwen"}, // no TraceID
+		IterateConfig{Tracer: tracer}, chat, validate)
+	if err != nil {
+		t.Fatalf("Iterate: %v", err)
+	}
+	if called != 0 {
+		t.Errorf("tracer should not fire without a trace_id; called=%d", called)
+	}
+	if resp.History[0].SpanID != "" {
+		t.Errorf("SpanID should be empty when no trace_id: %q", resp.History[0].SpanID)
+	}
+}
+
+// TestIterate_ChatCallerReceivesTraceID confirms the trace_id is
+// forwarded into the ChatCaller signature so HTTP transports can set
+// the X-Lakehouse-Trace-Id header. Without this, chatd's Langfuse
+// emit would create an orphan trace per retry instead of nesting
+// under the iterate parent.
+func TestIterate_ChatCallerReceivesTraceID(t *testing.T) {
+	var observedTrace string
+	chat := func(_ context.Context, _, _ string, _, _ string, _ *float64, _ int, traceID string) (string, error) {
+		observedTrace = traceID
+		return `{"k":"v"}`, nil
+	}
+	validate := func(_ string, _ map[string]any) (Report, error) { return Report{}, nil }
+	_, _, err := Iterate(context.Background(),
+		IterateRequest{Kind: "playbook", Prompt: "X", Provider: "ollama", Model: "x", TraceID: "trace-xyz"},
+		IterateConfig{}, chat, validate)
+	if err != nil {
+		t.Fatalf("Iterate: %v", err)
+	}
+	if observedTrace != "trace-xyz" {
+		t.Errorf("ChatCaller should receive trace_id; got %q", observedTrace)
+	}
+}
+
 func TestIterate_PropagatesChatInfraError(t *testing.T) {
-	chat := func(_ context.Context, _, _ string, _, _ string, _ *float64, _ int) (string, error) {
+	chat := func(_ context.Context, _, _ string, _, _ string, _ *float64, _ int, _ string) (string, error) {
 		return "", errors.New("connection refused")
 	}
 	validate := func(_ string, _ map[string]any) (Report, error) { return Report{}, nil }

internal/validator/session_log.go

@@ -0,0 +1,199 @@
+package validator
+
+import (
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+)
+
+// SessionRecordSchema versions the on-wire JSON shape. Bump when the
+// schema changes incompatibly. Consumers (e.g. duckdb queries over
+// coordinator_sessions.jsonl, scrum review tooling) check this field
+// to decide whether they understand the row.
+const SessionRecordSchema = "session.iterate.v1"
+
+// SessionRecord is one row in coordinator_sessions.jsonl. Captures the
+// full retry chain of a single /v1/iterate session for offline
+// forensics: "show me all sessions where the validator caught a
+// phantom worker" / "show me all sessions where retrieval missed."
+//
+// The Langfuse trace tree (see X-Lakehouse-Trace-Id propagation
+// 2026-05-02) is the live view; this JSONL is the longitudinal view
+// for ad-hoc DuckDB queries over thousands of sessions.
+type SessionRecord struct {
+	Schema           string                 `json:"schema"`
+	SessionID        string                 `json:"session_id"` // = Langfuse trace_id
+	Timestamp        string                 `json:"timestamp"`  // ISO 8601
+	Daemon           string                 `json:"daemon"`
+	Kind             string                 `json:"kind"`     // fill | email | playbook
+	Model            string                 `json:"model"`
+	Provider         string                 `json:"provider"`
+	Prompt           string                 `json:"prompt"` // truncated to 4000
+	Iterations       int                    `json:"iterations"`
+	MaxIterations    int                    `json:"max_iterations"`
+	FinalVerdict     string                 `json:"final_verdict"` // accepted | max_iter_exhausted | infra_error
+	Attempts         []SessionAttemptRecord `json:"attempts"`
+	Artifact         map[string]any         `json:"artifact,omitempty"` // present on success
+	GroundedInRoster *bool                  `json:"grounded_in_roster,omitempty"`
+	DurationMs       int64                  `json:"duration_ms"`
+}
+
+// SessionAttemptRecord mirrors IterateAttempt but stores only the
+// stable signals (iteration, verdict, error, span id). The raw model
+// output is intentionally NOT captured here — it lives in the
+// Langfuse span (queryable by span_id) and the iterate response. Two
+// copies would let the JSONL grow unbounded on long sessions.
+type SessionAttemptRecord struct {
+	Iteration   int    `json:"iteration"`
+	VerdictKind string `json:"verdict_kind"` // no_json | validation_failed | accepted
+	Error       string `json:"error,omitempty"`
+	SpanID      string `json:"span_id,omitempty"`
+}
+
+// SessionLogger appends SessionRecord rows to a JSONL file. Best-effort:
+// errors are logged via slog and never returned to the caller (per the
+// rest of the observability stack — never block a request because the
+// session log is unhappy).
+//
+// nil is a valid value: NewSessionLogger("") returns nil; Append on
+// a nil receiver is a no-op. Lets validatord skip the wiring entirely
+// when no session log is configured.
+type SessionLogger struct {
+	path string
+	mu   sync.Mutex
+}
+
+// NewSessionLogger constructs a logger writing to `path`. Empty path
+// disables logging. Creates parent dirs lazily on first write so the
+// constructor doesn't panic when the path is on a not-yet-mounted
+// volume (e.g. systemd unit ordering).
+func NewSessionLogger(path string) *SessionLogger {
+	if path == "" {
+		return nil
+	}
+	return &SessionLogger{path: path}
+}
+
+// Append writes one JSONL row. Returns nil on success or after a
+// best-effort failure. The caller doesn't need to handle errors;
+// logging is an observability witness, not a correctness gate.
+func (l *SessionLogger) Append(rec SessionRecord) {
+	if l == nil {
+		return
+	}
+	if rec.Schema == "" {
+		rec.Schema = SessionRecordSchema
+	}
+	if rec.Timestamp == "" {
+		rec.Timestamp = time.Now().UTC().Format(time.RFC3339Nano)
+	}
+	if rec.Daemon == "" {
+		rec.Daemon = "validatord"
+	}
+	body, err := json.Marshal(rec)
+	if err != nil {
+		slog.Warn("session_log: marshal", "err", err, "session_id", rec.SessionID)
+		return
+	}
+	body = append(body, '\n')
+
+	l.mu.Lock()
+	defer l.mu.Unlock()
+
+	if err := os.MkdirAll(filepath.Dir(l.path), 0o755); err != nil {
+		slog.Warn("session_log: mkdir", "err", err, "path", l.path)
+		return
+	}
+	f, err := os.OpenFile(l.path, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
+	if err != nil {
+		slog.Warn("session_log: open", "err", err, "path", l.path)
+		return
+	}
+	defer f.Close()
+	if _, err := f.Write(body); err != nil {
+		slog.Warn("session_log: write", "err", err, "session_id", rec.SessionID)
+	}
+}
+
+// BuildSessionRecord assembles a SessionRecord from an iterate
+// response/failure pair. Exactly one of resp/fail must be non-nil
+// (or both nil for an infrastructure failure). Centralized here so
+// validatord and any future iterate-using daemon emit the same shape.
+//
+// rosterCheck is called per accepted artifact to populate
+// GroundedInRoster — set to nil to skip the check (e.g. for
+// non-fill kinds that don't have worker IDs). Returns the shaped
+// record; pass to logger.Append on the caller side so failed
+// daemons don't block on their own observability layer.
+func BuildSessionRecord(
+	req IterateRequest,
+	resp *IterateResponse,
+	fail *IterateFailure,
+	infraErr error,
+	rosterCheck func(map[string]any) *bool,
+	durationMs int64,
+) SessionRecord {
+	rec := SessionRecord{
+		SessionID:     req.TraceID,
+		Kind:          req.Kind,
+		Model:         req.Model,
+		Provider:      req.Provider,
+		Prompt:        trim(req.Prompt, 4000),
+		MaxIterations: req.MaxIterations,
+		DurationMs:    durationMs,
+	}
+
+	switch {
+	case resp != nil:
+		rec.Iterations = resp.Iterations
+		rec.FinalVerdict = "accepted"
+		rec.Attempts = sessionAttemptsFromHistory(resp.History)
+		rec.Artifact = resp.Artifact
+		if rosterCheck != nil {
+			rec.GroundedInRoster = rosterCheck(resp.Artifact)
+		}
+		// Keep the trace id authoritative even if the request didn't
+		// supply one — the iterate response carries the resolved id.
+		if rec.SessionID == "" {
+			rec.SessionID = resp.TraceID
+		}
+	case fail != nil:
+		rec.Iterations = fail.Iterations
+		rec.FinalVerdict = "max_iter_exhausted"
+		rec.Attempts = sessionAttemptsFromHistory(fail.History)
+		if rec.SessionID == "" {
+			rec.SessionID = fail.TraceID
+		}
+	default:
+		// Infrastructure failure (chat hop crashed mid-loop, etc.).
+		// We still emit a row so the failure is forensically visible —
+		// otherwise long debugging sessions get harder.
+		rec.FinalVerdict = "infra_error"
+		if infraErr != nil {
+			rec.Attempts = []SessionAttemptRecord{{
+				Iteration:   0,
+				VerdictKind: "infra_error",
+				Error:       trim(fmt.Sprintf("%v", infraErr), 800),
+			}}
+		}
+	}
+
+	return rec
+}
+
+func sessionAttemptsFromHistory(h []IterateAttempt) []SessionAttemptRecord {
+	out := make([]SessionAttemptRecord, len(h))
+	for i, a := range h {
+		out[i] = SessionAttemptRecord{
+			Iteration:   a.Iteration,
+			VerdictKind: a.Status.Kind,
+			Error:       a.Status.Error,
+			SpanID:      a.SpanID,
+		}
+	}
+	return out
+}

internal/validator/session_log_test.go

@@ -0,0 +1,224 @@
+package validator
+
+import (
+	"bufio"
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"sync"
+	"testing"
+)
+
+func TestSessionLogger_AppendsSchemaTaggedRows(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "sessions.jsonl")
+	logger := NewSessionLogger(path)
+	if logger == nil {
+		t.Fatal("expected non-nil logger for a non-empty path")
+	}
+
+	rec := SessionRecord{
+		SessionID:    "trace-1",
+		Kind:         "fill",
+		Model:        "qwen3.5:latest",
+		Provider:     "ollama",
+		Prompt:       "produce a fill artifact",
+		Iterations:   1,
+		FinalVerdict: "accepted",
+	}
+	logger.Append(rec)
+
+	rows := readJSONL(t, path)
+	if len(rows) != 1 {
+		t.Fatalf("expected 1 row, got %d", len(rows))
+	}
+	if rows[0]["schema"] != SessionRecordSchema {
+		t.Errorf("schema autopopulation: %v", rows[0]["schema"])
+	}
+	if rows[0]["session_id"] != "trace-1" {
+		t.Errorf("session_id round-trip: %v", rows[0]["session_id"])
+	}
+	if rows[0]["timestamp"] == "" || rows[0]["timestamp"] == nil {
+		t.Errorf("timestamp autopopulation: %v", rows[0]["timestamp"])
+	}
+	if rows[0]["daemon"] != "validatord" {
+		t.Errorf("daemon autopopulation: %v", rows[0]["daemon"])
+	}
+}
+
+func TestSessionLogger_NilIsNoOp(t *testing.T) {
+	var logger *SessionLogger // nil
+	logger.Append(SessionRecord{SessionID: "trace-1"})
+	// No panic, no error — the test passing IS the assertion.
+}
+
+func TestSessionLogger_EmptyPathReturnsNil(t *testing.T) {
+	if NewSessionLogger("") != nil {
+		t.Error("empty path should disable logging (nil logger)")
+	}
+}
+
+// TestSessionLogger_ConcurrentAppends locks the per-row atomicity: N
+// goroutines each appending must produce N well-formed JSONL rows
+// with no torn writes. Mutex lives at the logger level, not OS-level,
+// so this also documents that concurrent logger instances would NOT
+// be safe (one logger per daemon — that's fine).
+func TestSessionLogger_ConcurrentAppends(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "sessions.jsonl")
+	logger := NewSessionLogger(path)
+
+	const N = 64
+	var wg sync.WaitGroup
+	for i := 0; i < N; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			logger.Append(SessionRecord{
+				SessionID:    "trace-" + string(rune('a'+i%26)),
+				Kind:         "fill",
+				FinalVerdict: "accepted",
+				Iterations:   i,
+			})
+		}(i)
+	}
+	wg.Wait()
+
+	rows := readJSONL(t, path)
+	if len(rows) != N {
+		t.Fatalf("expected %d rows after concurrent appends, got %d", N, len(rows))
+	}
+	// Every row must be parseable JSON — a torn write would throw
+	// a decode error, which readJSONL t.Fatal's on.
+}
+
+func TestBuildSessionRecord_SuccessPathCapturesArtifact(t *testing.T) {
+	req := IterateRequest{
+		TraceID:       "trace-x",
+		Kind:          "fill",
+		Prompt:        "produce fill",
+		Provider:      "ollama",
+		Model:         "qwen3.5:latest",
+		MaxIterations: 3,
+	}
+	resp := &IterateResponse{
+		Artifact: map[string]any{"fills": []any{
+			map[string]any{"candidate_id": "W-1"},
+		}},
+		Validation: Report{},
+		Iterations: 1,
+		History: []IterateAttempt{{
+			Iteration: 0,
+			Raw:       `{"fills":[{"candidate_id":"W-1"}]}`,
+			Status:    AttemptStatus{Kind: "accepted"},
+			SpanID:    "span-0",
+		}},
+		TraceID: "trace-x",
+	}
+	roster := func(_ map[string]any) *bool {
+		t := true
+		return &t
+	}
+	rec := BuildSessionRecord(req, resp, nil, nil, roster, 1234)
+	if rec.FinalVerdict != "accepted" || rec.Iterations != 1 {
+		t.Errorf("verdict/iterations: %+v", rec)
+	}
+	if rec.GroundedInRoster == nil || !*rec.GroundedInRoster {
+		t.Errorf("grounded_in_roster: expected true, got %v", rec.GroundedInRoster)
+	}
+	if rec.Artifact == nil {
+		t.Errorf("artifact missing on success path")
+	}
+	if len(rec.Attempts) != 1 || rec.Attempts[0].SpanID != "span-0" {
+		t.Errorf("attempts shape: %+v", rec.Attempts)
+	}
+	if rec.SessionID != "trace-x" {
+		t.Errorf("session_id: %s", rec.SessionID)
+	}
+	if rec.DurationMs != 1234 {
+		t.Errorf("duration: %d", rec.DurationMs)
+	}
+}
+
+func TestBuildSessionRecord_FailurePathOmitsArtifact(t *testing.T) {
+	req := IterateRequest{
+		TraceID:       "trace-y",
+		Kind:          "fill",
+		Provider:      "ollama",
+		Model:         "qwen",
+		MaxIterations: 3,
+	}
+	fail := &IterateFailure{
+		Error:      "max iterations reached (3)",
+		Iterations: 3,
+		History: []IterateAttempt{
+			{Iteration: 0, Status: AttemptStatus{Kind: "no_json"}},
+			{Iteration: 1, Status: AttemptStatus{Kind: "validation_failed", Error: "phantom W-X"}},
+			{Iteration: 2, Status: AttemptStatus{Kind: "validation_failed", Error: "phantom W-Y"}},
+		},
+		TraceID: "trace-y",
+	}
+	rec := BuildSessionRecord(req, nil, fail, nil, nil, 8765)
+	if rec.FinalVerdict != "max_iter_exhausted" {
+		t.Errorf("final_verdict: %s", rec.FinalVerdict)
+	}
+	if rec.Artifact != nil {
+		t.Errorf("artifact must be omitted on failure path: %v", rec.Artifact)
+	}
+	if rec.GroundedInRoster != nil {
+		t.Errorf("grounded_in_roster should be nil on failure: %v", *rec.GroundedInRoster)
+	}
+	if len(rec.Attempts) != 3 || rec.Attempts[2].VerdictKind != "validation_failed" {
+		t.Errorf("attempts: %+v", rec.Attempts)
+	}
+}
+
+func TestBuildSessionRecord_InfraErrorEmitsRow(t *testing.T) {
+	// An infrastructure failure (e.g. chat hop crashed) must STILL
+	// produce a session row — otherwise debugging gets harder
+	// (no log → operator can't see it failed at all).
+	req := IterateRequest{TraceID: "trace-z", Kind: "fill"}
+	rec := BuildSessionRecord(req, nil, nil, errExample{"chat refused"}, nil, 50)
+	if rec.FinalVerdict != "infra_error" {
+		t.Errorf("verdict: %s", rec.FinalVerdict)
+	}
+	if len(rec.Attempts) != 1 || rec.Attempts[0].VerdictKind != "infra_error" {
+		t.Errorf("attempts: %+v", rec.Attempts)
+	}
+	if rec.Attempts[0].Error == "" {
+		t.Errorf("error must be carried")
+	}
+}
+
+// ─── Helpers ───────────────────────────────────────────────────
+
+type errExample struct{ msg string }
+
+func (e errExample) Error() string { return e.msg }
+
+func readJSONL(t *testing.T, path string) []map[string]any {
+	t.Helper()
+	f, err := os.Open(path)
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	defer f.Close()
+	var out []map[string]any
+	sc := bufio.NewScanner(f)
+	sc.Buffer(make([]byte, 0, 1<<16), 1<<24)
+	for sc.Scan() {
+		line := sc.Bytes()
+		if len(line) == 0 {
+			continue
+		}
+		var row map[string]any
+		if err := json.Unmarshal(line, &row); err != nil {
+			t.Fatalf("parse line %q: %v", line, err)
+		}
+		out = append(out, row)
+	}
+	if err := sc.Err(); err != nil {
+		t.Fatalf("scan: %v", err)
+	}
+	return out
+}

internal/validator/types.go

@@ -19,7 +19,11 @@
 
 package validator
 
-import "time"
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
 
 // Artifact is the discriminated union of input shapes a Validator
 // can receive. Mirrors Rust's `enum Artifact`. The first non-zero
@@ -107,6 +111,94 @@ func (e *ValidationError) Error() string {
 	return string(e.Kind) + ": " + e.Reason
 }
 
+// MarshalJSON emits the Rust-compatible serde-tagged-enum shape:
+//
+//	{"Schema":       {"field": "...", "reason": "..."}}
+//	{"Completeness": {"reason": "..."}}
+//	{"Consistency":  {"reason": "..."}}
+//	{"Policy":       {"reason": "..."}}
+//
+// Aligns with `crates/validator/src/lib.rs::ValidationError` so callers
+// that parse the error envelope work across runtimes. Surfaced by the
+// 2026-05-02 cross-runtime parity probe (validator_parity.sh) which
+// found 5/6 body shapes diverging on identical input.
+func (e ValidationError) MarshalJSON() ([]byte, error) {
+	variant := variantName(e.Kind)
+	inner := map[string]string{}
+	if e.Kind == ErrSchema {
+		inner["field"] = e.Field
+	}
+	inner["reason"] = e.Reason
+	return json.Marshal(map[string]any{variant: inner})
+}
+
+// UnmarshalJSON accepts BOTH the Rust serde-tagged shape AND the
+// legacy flat-struct shape Go used to emit, so existing on-disk JSONL
+// rows still parse. New writes always use the Rust shape (per
+// MarshalJSON above).
+func (e *ValidationError) UnmarshalJSON(data []byte) error {
+	// Try the Rust serde shape first: {"<Variant>":{...}}
+	var tagged map[string]map[string]string
+	if err := json.Unmarshal(data, &tagged); err == nil && len(tagged) == 1 {
+		for variant, inner := range tagged {
+			kind, ok := kindFromVariant(variant)
+			if !ok {
+				return fmt.Errorf("unknown ValidationError variant %q", variant)
+			}
+			e.Kind = kind
+			e.Field = inner["field"]
+			e.Reason = inner["reason"]
+			return nil
+		}
+	}
+	// Fall back to the legacy flat shape: {"Kind":"...","Field":"...","Reason":"..."}
+	var flat struct {
+		Kind   ValidationErrorKind `json:"Kind"`
+		Field  string              `json:"Field"`
+		Reason string              `json:"Reason"`
+	}
+	if err := json.Unmarshal(data, &flat); err != nil {
+		return fmt.Errorf("ValidationError: neither serde nor flat shape: %w", err)
+	}
+	if flat.Kind == "" {
+		return fmt.Errorf("ValidationError: missing kind")
+	}
+	e.Kind = flat.Kind
+	e.Field = flat.Field
+	e.Reason = flat.Reason
+	return nil
+}
+
+// variantName maps the lowercase Go Kind to the CamelCase Rust serde
+// variant name. Kept in sync with `crates/validator/src/lib.rs::ValidationError`.
+func variantName(k ValidationErrorKind) string {
+	switch k {
+	case ErrSchema:
+		return "Schema"
+	case ErrCompleteness:
+		return "Completeness"
+	case ErrConsistency:
+		return "Consistency"
+	case ErrPolicy:
+		return "Policy"
+	}
+	return string(k) // fallback — preserves Kind for debugging
+}
+
+func kindFromVariant(v string) (ValidationErrorKind, bool) {
+	switch v {
+	case "Schema":
+		return ErrSchema, true
+	case "Completeness":
+		return ErrCompleteness, true
+	case "Consistency":
+		return ErrConsistency, true
+	case "Policy":
+		return ErrPolicy, true
+	}
+	return "", false
+}
+
 // Validator is the interface every validator implements.
 // Stateless — construction takes any deps (e.g. WorkerLookup)
 // upfront, validate() is pure on its inputs.

internal/validator/types_test.go

@@ -0,0 +1,97 @@
+package validator
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+// TestValidationError_MarshalsRustSerdeShape pins the on-wire JSON
+// envelope for cross-runtime parity with crates/validator's
+// `enum ValidationError`. Surfaced by the 2026-05-02 validator parity
+// probe (5/6 body-shape divergence pre-fix → 6/6 match post-fix).
+//
+// Failing this test = wire-format drift. Run the parity probe at
+// scripts/cutover/parity/validator_parity.sh to confirm Rust is
+// the source-of-truth shape this test is anchored to.
+func TestValidationError_MarshalsRustSerdeShape(t *testing.T) {
+	cases := []struct {
+		name    string
+		err     ValidationError
+		want    string
+	}{
+		{
+			name: "schema includes field+reason inside variant body",
+			err:  ValidationError{Kind: ErrSchema, Field: "fingerprint", Reason: "missing"},
+			want: `{"Schema":{"field":"fingerprint","reason":"missing"}}`,
+		},
+		{
+			name: "completeness only carries reason (no field key)",
+			err:  ValidationError{Kind: ErrCompleteness, Reason: "endorsed_names must be non-empty"},
+			want: `{"Completeness":{"reason":"endorsed_names must be non-empty"}}`,
+		},
+		{
+			name: "consistency only carries reason",
+			err:  ValidationError{Kind: ErrConsistency, Reason: "candidate_id W-1 not in roster"},
+			want: `{"Consistency":{"reason":"candidate_id W-1 not in roster"}}`,
+		},
+		{
+			name: "policy only carries reason",
+			err:  ValidationError{Kind: ErrPolicy, Reason: "client C-1 is on candidate's blacklist"},
+			want: `{"Policy":{"reason":"client C-1 is on candidate's blacklist"}}`,
+		},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			got, err := json.Marshal(c.err)
+			if err != nil {
+				t.Fatalf("marshal: %v", err)
+			}
+			if string(got) != c.want {
+				t.Errorf("\n got: %s\nwant: %s", got, c.want)
+			}
+		})
+	}
+}
+
+// TestValidationError_RoundTripsRustShape confirms a marshal+unmarshal
+// returns the same fields. Important: a Go side reading a Rust-written
+// ValidationError JSONL must populate Kind/Field/Reason correctly.
+func TestValidationError_RoundTripsRustShape(t *testing.T) {
+	original := ValidationError{Kind: ErrSchema, Field: "operation", Reason: "expected fill: prefix"}
+	body, err := json.Marshal(original)
+	if err != nil {
+		t.Fatalf("marshal: %v", err)
+	}
+	var decoded ValidationError
+	if err := json.Unmarshal(body, &decoded); err != nil {
+		t.Fatalf("unmarshal: %v", err)
+	}
+	if decoded.Kind != original.Kind || decoded.Field != original.Field || decoded.Reason != original.Reason {
+		t.Errorf("round-trip drift:\n  in: %+v\n out: %+v", original, decoded)
+	}
+}
+
+// TestValidationError_ParsesLegacyFlatShape ensures consumers reading
+// older Go-emitted JSONL still parse. This is the migration path for
+// any persisted error rows that pre-date the 2026-05-02 alignment.
+func TestValidationError_ParsesLegacyFlatShape(t *testing.T) {
+	legacy := []byte(`{"Kind":"schema","Field":"x","Reason":"y"}`)
+	var ve ValidationError
+	if err := json.Unmarshal(legacy, &ve); err != nil {
+		t.Fatalf("legacy shape should parse: %v", err)
+	}
+	if ve.Kind != ErrSchema || ve.Field != "x" || ve.Reason != "y" {
+		t.Errorf("legacy parse wrong: %+v", ve)
+	}
+}
+
+// TestValidationError_RejectsUnknownVariant catches drift if Rust adds
+// a new variant the Go side hasn't learned about yet — surfaces as a
+// parse error rather than a silent default.
+func TestValidationError_RejectsUnknownVariant(t *testing.T) {
+	body := []byte(`{"NewVariant":{"reason":"something"}}`)
+	var ve ValidationError
+	if err := json.Unmarshal(body, &ve); err == nil {
+		t.Errorf("expected error on unknown variant, got %+v", ve)
+	}
+}

lakehouse.toml

@@ -119,6 +119,13 @@ default_max_iterations = 3
 default_max_tokens = 4096
 # Chat hop timeout (seconds). 240s tolerates frontier reasoning models.
 chat_timeout_secs = 240
+# Session log: where to append one JSONL row per /v1/iterate session
+# for offline DuckDB analysis. Empty = disabled. Production:
+#   session_log_path = "/var/lib/lakehouse/validator/sessions.jsonl"
+# Each row: schema=session.iterate.v1, session_id (= Langfuse trace_id),
+# kind, model, iterations, attempts[], final_verdict, grounded_in_roster,
+# duration_ms. See internal/validator/session_log.go.
+session_log_path = ""
 
 [s3]
 endpoint        = "http://localhost:9000"

reports/cutover/gauntlet_2026-05-02/parity/embed_parity.md

@@ -0,0 +1,17 @@
+# /v1/embed cross-runtime parity probe
+
+**Date:** 2026-05-05T08:22:55Z
+**Rust:** `http://127.0.0.1:3100/ai/embed`  ·  **Go:** `http://127.0.0.1:4110/v1/embed`
+**Model:** `nomic-embed-text` (forced — overrides each side's default)
+**Match metric:** cosine similarity ≥ `0.99999`
+
+Identical text → both endpoints. Cosine compares vector
+DIRECTION (the operationally-meaningful property for HNSW
+retrieval); byte-equal isn't expected because Go round-trips
+through float32 internally while Rust stays at f64.
+
+**Tally:** 8 match · 0 diff (out of 8 fixtures)
+
+_Cosine ≥ 0.99999 on every fixture — embed parity holds_
+_post-sidecar-drop. Rust and Go produce vectors that point in_
+_the same direction in 768-dim space._

reports/cutover/gauntlet_2026-05-02/parity/extract_json_parity.md

@@ -0,0 +1,14 @@
+# extract_json parity probe — Rust vs Go
+
+**Date:** 2026-05-05T08:23:07Z
+**Rust helper:** `/home/profit/lakehouse/target/release/parity_extract_json` (links live `gateway::v1::iterate::extract_json`)
+**Go helper:** `./bin/parity_extract_json_go` (links live `internal/validator.ExtractJSON`)
+
+Identical model-output strings → both runtimes' `extract_json`.
+Match = identical `{matched, value}` JSON output.
+
+**Substrate gate:** `cargo test -p gateway extract_json` PASS before probe.
+
+**Tally:** 12 match · 0 diff (out of 12 fixtures)
+
+_No divergences — extract_json parity holds across all fixtures._

reports/cutover/gauntlet_2026-05-02/parity/materializer_parity.md

@@ -0,0 +1,13 @@
+# Materializer parity probe — Bun vs Go
+
+**Date:** 2026-05-05T08:23:08Z
+**Bun:** `/home/profit/lakehouse/scripts/distillation/build_evidence_index.ts`
+**Go:**  `./bin/materializer`
+
+Identical `data/_kb/` source → both runtimes' materializer.
+Match = JSONL byte-equal after normalizing `provenance.recorded_at`
+(per-run wall clock) + sorted line order (dedup ordering).
+
+**Tally:** 2 match · 0 diff (out of 2 stems)
+
+_No divergences — on-wire JSON parity holds._

reports/cutover/gauntlet_2026-05-02/parity/session_log_parity.md

@@ -0,0 +1,15 @@
+# session_log parity probe — Rust gateway vs Go validatord
+
+**Date:** 2026-05-05T08:23:08Z
+**Rust helper:** `/home/profit/lakehouse/target/release/parity_session_log`
+**Go helper:** `./bin/parity_session_log_go`
+
+Identical fixture inputs through each runtime's
+`SessionRecord` builder + JSON marshaler. Match = byte-equal
+after stripping `timestamp` (per-run wall clock) + `daemon`
+("gateway" on Rust side, "validatord" on Go side; both are
+valid producers in the same longitudinal log).
+
+**Tally:** 4 match · 0 diff (out of 4 fixtures)
+
+_No divergences — schema parity holds across all fixtures._

reports/cutover/gauntlet_2026-05-02/parity/subject_audit_parity.md

@@ -0,0 +1,31 @@
+# subject_audit_parity
+
+**Generated:** 2026-05-05 08:23:08 UTC
+**Spec:** /home/profit/lakehouse/docs/specs/SUBJECT_MANIFESTS_ON_CATALOGD.md §5 Step 8
+**Rust helper:** `/home/profit/lakehouse/target/release/parity_subject_audit`
+**Go helper:** `./bin/subject_audit_helper`
+**Audit dir:** `/home/profit/lakehouse/data/_catalog/subjects`
+
+## Phase 1 — Known-answer vector
+
+Hardcoded fixture row, identical inputs, byte-compare canonical-JSON + HMAC.
+
+**MATCH** ✓
+
+```json
+{"mode":"known_answer","canonical":"{\"accessor\":{\"daemon\":\"gateway\",\"kind\":\"gateway_lookup\",\"purpose\":\"parity_test\",\"trace_id\":\"trace-fixed\"},\"candidate_id\":\"WORKER-FIXED\",\"fields_accessed\":[\"name\"],\"prev_chain_hash\":\"GENESIS\",\"result\":\"success\",\"schema\":\"subject_audit.v1\",\"ts\":\"2026-05-03T12:00:00Z\"}","hmac":"f730fa038c847c27386b92eb1939ec64c62086c0a92617ac0bdf9f650c390b96","canonical_bytes_len":266}
+```
+
+## Phase 2 — Real production audit logs
+
+Every `*.audit.jsonl` in `/home/profit/lakehouse/data/_catalog/subjects` verified by both runtimes.
+
+**SKIP** — signing key not readable at `/tmp/lakehouse_audit/subject_audit.key`.
+Set `KEY_PATH=...` or seed /tmp/lakehouse_audit/subject_audit.key (see systemd unit).
+
+
+## Summary
+
+**1 / 1** parity assertions passed.
+
+**Status: PARITY** — every Rust assertion matches Go byte-for-byte.

reports/cutover/gauntlet_2026-05-02/parity/validator_parity.md

@@ -1,6 +1,6 @@
 # Validator parity probe — Rust :3100 vs Go :4110
 
-**Date:** 2026-05-02T08:59:17Z
+**Date:** 2026-05-05T08:23:08Z
 **Rust gateway:** `http://127.0.0.1:3100`  ·  **Go gateway:** `http://127.0.0.1:4110`
 
 Identical `POST /v1/validate` request → both runtimes. Match
@@ -9,124 +9,11 @@ Identical `POST /v1/validate` request → both runtimes. Match
 | Case | Rust status | Go status | Status match | Body match |
 |---|---:|---:|:---:|:---:|
 | playbook_happy | 200 | 200 | ✓ | ✓ |
-| playbook_missing_fingerprint | 422 | 422 | ✓ | ✗ |
-| playbook_wrong_prefix | 422 | 422 | ✓ | ✗ |
-| playbook_empty_endorsed | 422 | 422 | ✓ | ✗ |
-| playbook_overfull | 422 | 422 | ✓ | ✗ |
-| fill_phantom | 422 | 422 | ✓ | ✗ |
+| playbook_missing_fingerprint | 422 | 422 | ✓ | ✓ |
+| playbook_wrong_prefix | 422 | 422 | ✓ | ✓ |
+| playbook_empty_endorsed | 422 | 422 | ✓ | ✓ |
+| playbook_overfull | 422 | 422 | ✓ | ✓ |
+| fill_phantom | 422 | 422 | ✓ | ✓ |
 
-**Tally:** 1 match · 5 diff (out of 6 cases)
+**Tally:** 6 match · 0 diff (out of 6 cases)
 
-## Divergences
-
-<details><summary>DIFF — `playbook_missing_fingerprint`</summary>
-
-**Rust** (HTTP 422):
-```json
-{
-  "Schema": {
-    "field": "fingerprint",
-    "reason": "missing — required for Phase 25 validity window"
-  }
-}
-```
-
-**Go** (HTTP 422):
-```json
-{
-  "Field": "fingerprint",
-  "Kind": "schema",
-  "Reason": "missing — required for Phase 25 validity window"
-}
-```
-
-</details>
-
-<details><summary>DIFF — `playbook_wrong_prefix`</summary>
-
-**Rust** (HTTP 422):
-```json
-{
-  "Schema": {
-    "field": "operation",
-    "reason": "expected `fill: ...` prefix, got \"sms_draft: hello\""
-  }
-}
-```
-
-**Go** (HTTP 422):
-```json
-{
-  "Field": "operation",
-  "Kind": "schema",
-  "Reason": "expected `fill: ...` prefix, got \"sms_draft: hello\""
-}
-```
-
-</details>
-
-<details><summary>DIFF — `playbook_empty_endorsed`</summary>
-
-**Rust** (HTTP 422):
-```json
-{
-  "Completeness": {
-    "reason": "endorsed_names must be non-empty"
-  }
-}
-```
-
-**Go** (HTTP 422):
-```json
-{
-  "Field": "",
-  "Kind": "completeness",
-  "Reason": "endorsed_names must be non-empty"
-}
-```
-
-</details>
-
-<details><summary>DIFF — `playbook_overfull`</summary>
-
-**Rust** (HTTP 422):
-```json
-{
-  "Completeness": {
-    "reason": "endorsed_names (3) exceeds target_count × 2 (2)"
-  }
-}
-```
-
-**Go** (HTTP 422):
-```json
-{
-  "Field": "",
-  "Kind": "completeness",
-  "Reason": "endorsed_names (3) exceeds target_count × 2 (2)"
-}
-```
-
-</details>
-
-<details><summary>DIFF — `fill_phantom`</summary>
-
-**Rust** (HTTP 422):
-```json
-{
-  "Consistency": {
-    "reason": "fills[0].candidate_id \"W-PHANTOM-NEVER-EXISTS\" does not exist in worker roster"
-  }
-}
-```
-
-**Go** (HTTP 422):
-```json
-{
-  "Field": "",
-  "Kind": "consistency",
-  "Reason": "fills[0].candidate_id \"W-PHANTOM-NEVER-EXISTS\" does not exist in worker roster"
-}
-```
-
-</details>

reports/reality-tests/playbook_lift_real_006.md

@@ -0,0 +1,151 @@
+# Playbook-Lift Reality Test — Run real_006
+
+**Generated:** 2026-05-05T09:50:08.929241389Z
+**Judge:** `qwen2.5:latest` (Ollama, resolved from env JUDGE_MODEL=qwen2.5:latest)
+**Corpora:** `workers,ethereal_workers`
+**Workers limit:** 5000
+**Queries:** `tests/reality/real_coord_queries_v3.txt` (50 executed)
+**K per pass:** 10
+**Paraphrase pass:** ENABLED
+**Re-judge pass:** ENABLED
+**Evidence:** `reports/reality-tests/playbook_lift_real_006.json`
+
+---
+
+## Headline
+
+| Metric | Value |
+|---|---:|
+| Total queries run | 50 |
+| Cold-pass discoveries (judge-best ≠ top-1) | 9 |
+| Warm-pass lifts (recorded playbook → top-1) | 9 |
+| No change (judge-best already top-1, no playbook needed) | 41 |
+| Playbook boosts triggered (warm pass) | 10 |
+| Mean Δ top-1 distance (warm − cold) | -0.05014307 |
+| **Paraphrase pass — recorded answer at rank 0 (top-1)** | **6 / 9** |
+| Paraphrase pass — recorded answer at any rank in top-K | 9 / 9 |
+| **Quality lift** (warm top-1 rating > cold top-1 rating) | **11 / 50** |
+| Quality neutral (warm top-1 rating = cold top-1 rating) | 36 / 50 |
+| Quality regressed (warm top-1 rating < cold top-1 rating) | 3 / 50 |
+
+**Verbatim lift rate:** 9 of 9 discoveries became top-1 after warm pass.
+
+---
+
+## Per-query results
+
+| # | Query | Cold top-1 | Cold judge-best (rank/rating) | Recorded? | Warm top-1 | Judge-best warm rank | Lift |
+|---|---|---|---|---|---|---|---|
+| 1 | Need 1 Loader in Kansas City MO starting at 17:30 for Corner | w-4806 | 0/5 | — | w-4806 | 0 | no |
+| 2 | Need 2 Assemblers in Cincinnati OH starting at 14:30 for Gre | w-4371 | 0/4 | — | w-4371 | 0 | no |
+| 3 | Need 1 Forklift Operator in Lexington KY starting at 08:30 f | e-8263 | 1/5 | ✓ w-4636 | w-4636 | 0 | **YES** |
+| 4 | Need 2 Assemblers in Flint MI starting at 08:30 for Centenni | e-7186 | 1/4 | ✓ e-9319 | e-9319 | 0 | **YES** |
+| 5 | Need 2 Welders in Indianapolis IN starting at 10:00 for Nort | e-5834 | 0/4 | — | e-5834 | 0 | no |
+| 6 | Need 2 Material Handlers in Cincinnati OH starting at 13:00  | e-4871 | 4/2 | — | e-4871 | 4 | no |
+| 7 | Need 3 Pickers in Flint MI starting at 17:00 for Centennial  | e-5571 | 0/2 | — | e-5571 | 0 | no |
+| 8 | Need 3 Packers in Indianapolis IN starting at 09:00 for Heri | w-279 | 0/4 | — | w-279 | 0 | no |
+| 9 | Need 3 Assemblers in Columbus OH starting at 17:30 for River | w-281 | 0/4 | — | w-281 | 0 | no |
+| 10 | Need 5 Machine Operators in Cleveland OH starting at 14:30 f | e-8279 | 0/4 | — | e-8279 | 0 | no |
+| 11 | Need 2 Assemblers in Grand Rapids MI starting at 13:00 for C | w-4502 | 0/3 | — | w-4502 | 0 | no |
+| 12 | Need 2 Pickers in Akron OH starting at 10:30 for Summit Indu | e-5655 | 2/2 | — | e-5655 | 2 | no |
+| 13 | Need 3 Quality Techs in Lexington KY starting at 12:30 for K | e-6369 | 0/4 | — | e-6369 | 0 | no |
+| 14 | Need 4 Assemblers in Gary IN starting at 12:00 for Heritage  | e-1315 | 0/2 | — | e-1315 | 0 | no |
+| 15 | Need 3 Packers in Toledo OH starting at 16:00 for Cornerston | e-4887 | 1/2 | — | e-4887 | 1 | no |
+| 16 | Need 4 Warehouse Associates in Fort Wayne IN starting at 13: | w-4434 | 0/4 | — | w-4434 | 0 | no |
+| 17 | Need 4 Assemblers in Columbus OH starting at 13:00 for Midwa | w-281 | 0/4 | — | w-281 | 0 | no |
+| 18 | Need 2 Shipping Clerks in Chicago IL starting at 17:00 for M | w-4504 | 1/4 | ✓ w-1522 | w-1522 | 0 | **YES** |
+| 19 | Need 2 Machine Operators in Chicago IL starting at 11:00 for | e-1251 | 0/4 | — | e-1251 | 0 | no |
+| 20 | Need 3 CNC Operators in Grand Rapids MI starting at 10:00 fo | w-792 | 0/3 | — | w-792 | 0 | no |
+| 21 | Need 1 Warehouse Associate in Lexington KY starting at 09:30 | e-2331 | 0/4 | — | e-2331 | 0 | no |
+| 22 | Need 2 Material Handlers in Gary IN starting at 11:00 for He | e-18 | 0/2 | — | e-18 | 0 | no |
+| 23 | Need 5 Assemblers in Fort Wayne IN starting at 16:30 for Mid | e-6271 | 7/3 | — | e-6271 | 7 | no |
+| 24 | Need 1 Loader in Cincinnati OH starting at 08:00 for Summit  | e-8843 | 1/5 | ✓ w-4473 | w-4473 | 0 | **YES** |
+| 25 | Need 3 Quality Techs in Columbus OH starting at 12:00 for Ri | w-281 | 0/2 | — | w-281 | 0 | no |
+| 26 | Need 1 Machine Operator in Columbus OH starting at 09:30 for | w-4815 | 0/4 | — | w-4815 | 0 | no |
+| 27 | Need 3 Machine Operators in Madison WI starting at 12:00 for | w-2027 | 0/4 | — | w-2027 | 0 | no |
+| 28 | Need 2 Material Handlers in Kansas City MO starting at 11:30 | e-6774 | 0/3 | — | e-6774 | 0 | no |
+| 29 | Need 3 Loaders in Flint MI starting at 16:00 for Parallel Ma | w-4875 | 0/2 | — | w-4875 | 0 | no |
+| 30 | Need 2 Welders in Louisville KY starting at 13:00 for Horizo | w-2267 | 0/4 | — | w-2267 | 0 | no |
+| 31 | Need 1 CNC Operator in Flint MI starting at 10:30 for Horizo | e-317 | 7/3 | — | e-317 | 7 | no |
+| 32 | Need 1 Material Handler in Columbus OH starting at 15:30 for | e-8676 | 1/4 | ✓ w-2589 | w-2589 | 0 | **YES** |
+| 33 | Need 2 Forklift Operators in Louisville KY starting at 14:30 | w-1830 | 0/4 | — | w-1830 | 0 | no |
+| 34 | Need 2 Warehouse Associates in Chicago IL starting at 10:00  | w-4743 | 7/4 | ✓ e-9171 | e-9171 | 0 | **YES** |
+| 35 | Need 2 Material Handlers in Gary IN starting at 15:00 for Pa | w-4236 | 1/2 | — | w-4236 | 1 | no |
+| 36 | Need 1 Forklift Operator in Grand Rapids MI starting at 10:0 | w-3227 | 3/2 | — | w-3227 | 3 | no |
+| 37 | Need 2 Pickers in Louisville KY starting at 12:30 for Corner | e-6489 | 2/4 | ✓ e-7622 | e-7622 | 0 | **YES** |
+| 38 | Need 2 Loaders in Indianapolis IN starting at 17:30 for Midw | e-9877 | 0/4 | — | e-9877 | 0 | no |
+| 39 | Need 1 Shipping Clerk in Indianapolis IN starting at 12:30 f | w-4635 | 0/5 | — | w-4635 | 0 | no |
+| 40 | Need 2 Assemblers in Cincinnati OH starting at 08:00 for Key | w-4945 | 0/4 | — | w-4945 | 0 | no |
+| 41 | Need 5 Quality Techs in Kansas City MO starting at 11:30 for | e-5633 | 0/4 | — | e-5633 | 0 | no |
+| 42 | Need 2 Machine Operators in Gary IN starting at 10:00 for He | e-1089 | 0/2 | — | e-1089 | 0 | no |
+| 43 | Need 1 Packer in Chicago IL starting at 09:30 for Midway Dis | e-7746 | 0/5 | — | w-279 | 1 | no |
+| 44 | Need 2 Pickers in Lexington KY starting at 17:30 for Vanguar | e-3375 | 0/4 | — | e-3375 | 0 | no |
+| 45 | Need 2 Maintenance Techs in Grand Rapids MI starting at 17:0 | e-6083 | 0/2 | — | e-6083 | 0 | no |
+| 46 | Need 1 Material Handler in Detroit MI starting at 10:30 for  | w-3286 | 0/5 | — | w-3286 | 0 | no |
+| 47 | Need 1 Welder in Akron OH starting at 15:00 for Summit Indus | e-6149 | 0/2 | — | e-6149 | 0 | no |
+| 48 | Need 1 Shipping Clerk in Cincinnati OH starting at 13:30 for | e-4218 | 3/5 | ✓ w-3488 | w-3488 | 0 | **YES** |
+| 49 | Need 5 Packers in Indianapolis IN starting at 10:30 for Midw | e-2746 | 2/4 | ✓ w-279 | w-279 | 0 | **YES** |
+| 50 | Need 1 Forklift Operator in Louisville KY starting at 10:30  | w-1830 | 0/4 | — | w-1830 | 0 | no |
+
+---
+
+## Paraphrase pass — does the playbook help similar-but-different queries?
+
+For each query whose Pass 1 cold pass recorded a playbook entry, the
+judge model rephrased the query, and the rephrased version was sent
+through warm matrix.search. The recorded answer ID's rank in those
+results tests whether cosine on the embedded paraphrase finds the
+recorded query's vector.
+
+| # | Original (≤40c) | Paraphrase (≤60c) | Recorded answer | Paraphrase top-1 | Recorded rank | Paraphrase lift |
+|---|---|---|---|---|---|---|
+| 3 | Need 1 Forklift Operator in Lexington KY | Vanguard Components requires a Forklift Operator in Lexingto | w-4636 | w-4636 | 0 | **YES** |
+| 4 | Need 2 Assemblers in Flint MI starting a | Centennial Packaging requires 2 Assemblers to start at 08:30 | e-9319 | e-9319 | 0 | **YES** |
+| 18 | Need 2 Shipping Clerks in Chicago IL sta | Looking for 2 Shipping Clerks in Chicago, IL to start at 5:0 | w-1522 | w-4504 | 1 | no |
+| 24 | Need 1 Loader in Cincinnati OH starting  | Summit Industrial requires 1 Loader position from 08:00 onwa | w-4473 | w-4473 | 0 | **YES** |
+| 32 | Need 1 Material Handler in Columbus OH s | Looking for a Material Handler in Columbus, OH who can start | w-2589 | w-2589 | 0 | **YES** |
+| 34 | Need 2 Warehouse Associates in Chicago I | Looking for 2 Warehouse Associates to work from 10:00 onward | e-9171 | e-9171 | 0 | **YES** |
+| 37 | Need 2 Pickers in Louisville KY starting | Looking for 2 Pickers in Louisville, KY to start at 12:30 fo | e-7622 | e-6489 | 2 | no |
+| 48 | Need 1 Shipping Clerk in Cincinnati OH s | Summit Industrial requires a Shipping Clerk in Cincinnati, O | w-3488 | w-3488 | 0 | **YES** |
+| 49 | Need 5 Packers in Indianapolis IN starti | Looking for 5 packers in Indianapolis, IN to start at 10:30  | w-279 | e-2746 | 1 | no |
+
+---
+
+## Honesty caveats
+
+1. **Judge IS the ground truth proxy.** Without human-labeled relevance, the LLM
+   judge's verdict is what defines "best." If `qwen2.5:latest` rates badly,
+   the lift number is meaningless. To validate the judge itself, sample 5–10
+   verdicts manually and check agreement.
+2. **Score-1.0 boost = distance halved.** Playbook math is
+   `distance' = distance × (1 - 0.5 × score)`. Lift requires the judge-best
+   result's pre-boost distance to be ≤ 2× the cold top-1's distance, otherwise
+   even halving doesn't promote it. Tight clusters → little visible lift.
+3. **Verbatim vs paraphrase.** The verbatim lift rate (above) is the cheap
+   case — same query, recorded playbook, expected boost. The paraphrase
+   pass (when enabled) is the actual learning property: similar-but-different
+   queries hitting a recorded playbook. Compare verbatim and paraphrase
+   lift rates — paraphrase should be lower (semantic-distance gates some
+   playbook hits) but non-zero is the meaningful signal.
+4. **Multi-corpus skew.** Default corpora=`workers,ethereal_workers` — if all judge-best
+   results land in one corpus, the matrix layer's purpose isn't being tested.
+   Check per-corpus distribution in the JSON.
+5. **Judge resolution.** This run used `qwen2.5:latest` from
+   env JUDGE_MODEL=qwen2.5:latest.
+   Bumping the judge for run #N+1 means editing one line in lakehouse.toml.
+6. **Paraphrase generation also uses the judge.** The same model that rates
+   relevance also rephrases queries. A judge that's bad at rating staffing
+   queries is probably also bad at rephrasing them. Worth sanity-checking
+   a sample of `paraphrase_query` values in the JSON before trusting the
+   paraphrase lift number.
+
+## Next moves
+
+- If lift rate ≥ 50% of discoveries: matrix layer + playbook is doing real
+  work. Move to paraphrase queries + tag-based boost (currently ignored).
+- If lift rate < 20%: investigate why — judge variance, distance gap too
+  wide, or playbook math too gentle. The score=1.0 / 0.5× formula may need
+  retuning.
+- If discovery rate (cold judge-best ≠ top-1) is itself low: cosine is
+  already close to optimal on this query distribution. Either the corpus
+  is too narrow or the queries are too easy.

reports/reality-tests/real_006_findings.md

@@ -0,0 +1,234 @@
+# Reality test real_006 — distribution-shift findings
+
+**Run:** 2026-05-05 04:41:46 → 04:50:08 CDT (8m22s driver wall, ~14 min including ingest)
+**Judge:** `qwen2.5:latest` (Ollama, local) — anchor's recommended judge, ~9s/query
+**Queries:** 50 from `tests/reality/real_coord_queries_v3.txt` (rows 10-59 of fill_events.parquet, single `need` style)
+**Corpora:** `workers,ethereal_workers` (5K + 10K)
+**Local-only:** zero cloud calls per PRD line 70.
+
+Companion to `playbook_lift_real_006.{json,md}`. That's the harness output; this is the reading.
+
+---
+
+## Why this test exists
+
+real_001-005 all sourced their queries from the **first 10 rows** of
+`fill_events.parquet`. `gen_real_queries.go` had `-limit N` but no
+`-offset N`, so every "real" reality test ran on the same memorized
+slice. The published "8 / 10 cold-pass top-1 = judge-best" was a
+property of those 10 rows, not measured generalization. real_006
+closes the methodology gap: new `-offset` flag samples rows 10-59 (5×
+the count, never seen by the substrate).
+
+---
+
+## Headline — substrate generalizes (mostly)
+
+| Metric | real_001 (10 queries, rows 0-9) | real_006 (50 queries, rows 10-59) | Verdict |
+|---|---:|---:|---|
+| Cold-pass top-1 = judge-best (rank match) | 8 / 10 (80%) | **41 / 50 (82%)** | **HOLDS** |
+| Cold-pass top-1 = judge-best AND rating ≥ 2 | 8 / 10 (80%) | 34 / 50 (68%) | -12 pts |
+| Mean cold top-1 judge rating | ~3.3 | 3.08 | -7% |
+| Discoveries (judge promoted non-top-1) | 2 / 10 | 9 / 50 (18%) | comparable |
+| Verbatim lift (discovery → warm top-1) | 2 / 2 (100%) | 9 / 9 (100%) | **HOLDS** |
+| Paraphrase recovery → top-1 | n/a (disabled) | 6 / 9 (67%) | new |
+| Quality regressed on rejudge | 0 (test absent) | 3 / 50 (6%) | new |
+
+**Reading:** the substrate's *rank* behavior generalizes cleanly — the
+top-1 worker is judge-approved at the same rate on fresh data as on
+memorized data. The *quality* of top-1 (rating ≥ 2) drops 12 points,
+which means 7 of the 41 "no-discovery" queries had cold top-1 the
+judge rated 1 (irrelevant) but the corpus had nothing better. Honest
+signal: parts of the v3 slice are in territory the workers corpus
+doesn't cover well.
+
+The verbatim-lift property (discovery → warm top-1) is **clean at
+9/9**, matching real_001's 2/2 perfectly. When the playbook records,
+the recorded answer comes back next time. That's the load-bearing
+learning property.
+
+---
+
+## Cluster analysis — the cross-pollination question
+
+real_001 found that same-(client, city) clusters cause Shape A boost
+to bleed across roles. Real_002's role-gate fix (`roleEqual`) was
+supposed to close that. real_006 has *more* cluster opportunities than
+real_001 did:
+
+| Cluster | Count | Result |
+|---|---:|---|
+| Riverfront Steel + Columbus OH | 4 | mostly clean — see below |
+| Heritage Foods + Gary IN | 3 | **clean** — distinct workers per role, no boost firing |
+| Cornerstone Fabrication + Louisville KY | 3 | clean |
+| Midway Distribution + Chicago IL | 3 | **bleed: Q43 regressed** |
+
+### Heritage Foods + Gary IN (3 queries, all clean)
+
+```
+Q14 Assemblers       → e-1315
+Q22 Material Handler → e-18
+Q42 Machine Operator → e-1089
+```
+
+Three different roles → three different workers. Zero boosts fired,
+zero playbooks recorded. **Role-disambiguation works at the cosine
+level for this cluster.** Comparable to real_002's role-gate
+demonstration.
+
+### Riverfront Steel + Columbus OH (4 queries, partial)
+
+```
+Q9  Assemblers       → w-281    (cold = warm, no boost)
+Q25 Quality Techs    → w-281    (cold = warm, no boost) ← same worker as Q9!
+Q26 Machine Operator → w-4815   (clean)
+Q32 Material Handler → e-8676 → w-2589  (judge promoted, playbook recorded)
+```
+
+Q9 and Q25 both surface `w-281` cold-pass for *different roles* —
+that's a **cosine-level confusion** in the workers corpus, not a
+playbook bleed. The substrate isn't breaking; the corpus contains a
+worker whose resume embeds close to both "Assemblers" and "Quality
+Techs" in this client+city. Judge-rating Q25 dropped 2 → 1 on
+rejudge, which is the LLM's own consistency drift, not a substrate
+fault. Worth noting but not a bug.
+
+### Midway Distribution + Chicago IL (3 queries) — the regression
+
+```
+Q18 Shipping Clerks   → cold w-4504 → warm w-1522  (boost=1, playbook recorded)
+Q19 Machine Operators → cold = warm e-1251         (clean)
+Q43 Packer            → cold e-7746 (rating 5) → warm w-279 (rating 2)  ← regressed
+```
+
+**Diagnosis (2026-05-05 follow-up): the leak source isn't Q18 — it's Q49.**
+
+Three queries in real_006 touch `w-279`:
+
+| # | role-extract | client | city | result | playbook? |
+|---|---|---|---|---|---|
+| Q8 Packers Indianapolis IN Heritage Foods | Packers | Heritage Foods | Indianapolis | w-279 (cold = judge-best) | no |
+| **Q49** Packers **Indianapolis IN** Midway Distribution | Packers | **Midway Distribution** | Indianapolis | cold e-2746 → warm w-279 (judge-best) | **yes — recorded** |
+| Q43 Packer **Chicago IL** Midway Distribution | Packer | **Midway Distribution** | Chicago | cold e-7746 (rating 5) → warm w-279 (rating 2) | no |
+
+Q49 recorded `w-279` with role=`Packers`, client=`Midway Distribution`,
+city=`Indianapolis`. When Q43 ran with role=`Packer`,
+client=`Midway Distribution`, city=`Chicago`:
+
+- `roleEqual("Packer", "Packers")` → both normalize to `"packer"` →
+  **gate passes (correctly, by design)**
+- Q49's recorded query embedding is close enough to Q43's that the
+  playbook hit's distance falls inside `DefaultPlaybookMaxInjectDistance = 0.20`
+  (role + client + count + time-token dominate cosine; only the city
+  and the singular/plural noun differ)
+- Inject fires; `w-279` (an Indianapolis worker) surfaces at Q43's
+  warm top-1 in **Chicago**
+- Judge correctly rates this 2/5 — wrong city
+
+**The role gate IS working as designed.** What's missing is a
+**city gate** (or more generally, a metadata-equality gate on the
+demand attributes that don't appear in the role field). Real_002's
+fix anticipated cross-role bleed (Forklift → CNC); it didn't
+anticipate cross-city bleed within the same client+role.
+
+**Why prior tests missed this:** real_001-005 sourced from rows 0-9
+of fill_events.parquet. Among those 10 rows there was no
+Midway-Distribution × Packer × (different cities) pair. real_006
+includes rows 10-59 which contain Q43 (Chicago) and Q49 (Indianapolis)
+on the same client+role — a structurally new combination the
+substrate hadn't been tested against.
+
+The methodology gap closing on itself: the offset-flag fix that
+surfaced real_006's headline number (-12 pts strict) also surfaced
+a real cross-city leak the gate doesn't catch.
+
+**The other regressions** (Q4 Centennial Packaging Flint, Q25
+Riverfront Steel Quality Techs) are smaller (3→2 and 2→1) and look
+like judge consistency drift on borderline candidates. Q43 is the
+structural one.
+
+### Concrete fix surface (next session)
+
+A city gate alongside the role gate would close this:
+
+1. **`PlaybookEntry`** gains `City string` (or generalize to
+   `Metadata map[string]string`). Recorded at `playbookRecord` time
+   from the same query the role extractor parses.
+2. **`InjectPlaybookMisses` + `ApplyPlaybookBoost`** add a
+   `cityEqual(queryCity, hit.Entry.City)` check after the role
+   check. Same "permissive on empty" semantics as `roleEqual`.
+3. **Bin extractor** adds a city-extract regex (e.g.
+   `\s+in\s+([A-Z][a-z]+(?:\s+[A-Z][a-z]+)*)\s+[A-Z]{2}`) to capture
+   the city + state token from the standard query shape.
+4. **Unit tests** mirror the existing role-gate tests, locking the
+   exact Q43/Q49 scenario as a regression gate (and add an integration-
+   level test that record(role=Packers, city=Indianapolis) followed by
+   search(role=Packer, city=Chicago) doesn't surface the recorded
+   answer).
+
+Estimated scope: 1 new field, 2 new gate checks, 1 new regex, ~5
+tests. Same shape as real_002's role-gate fix. Half a session.
+
+Open question: same-metro normalization ("Detroit MI" ≈ "Dearborn MI"?)
+would help with real-world dispatch where coordinators legitimately
+route across nearby cities. Punt that to future work — strict equality
+closes the structural bleed without over-engineering.
+
+---
+
+## What this confirms vs falsifies
+
+**Confirmed:**
+- Substrate generalizes at the rank level (82% cold-top-1 = judge-best)
+- Verbatim lift works (9/9 discoveries → warm top-1)
+- Role-disambiguation works at cosine level for clean role-distinct
+  query distributions (Heritage Foods cluster is the proof)
+- Paraphrase recovery is real (6/9 → top-1, 9/9 any-rank)
+
+**Falsified / weakened:**
+- "8/10 cold-pass top-1 = judge-best" was 12 points optimistic on
+  the strict (rating ≥ 2) interpretation. Real number on broader
+  data is ~68%, not 80%. Headline rank-match number (82%) holds.
+- Real_002's role-gate fix is **not structurally airtight**. Q43
+  shows the cluster-bleed pattern can still fire under conditions
+  the prior tests didn't reach. Open question: which path is
+  leaking — extractor failure, gate scope, or cosine drift?
+
+---
+
+## Next moves (informed by this evidence)
+
+1. **Diagnose Q43 specifically**: re-run the role extractor on its
+   query text, check whether Q18's playbook entry has a role field
+   recorded, look at the warm-pass top-K to see whether `w-279`
+   reaches there via boost, inject, or cosine-only.
+2. **Strengthen the corpus for the role-city combos that scored
+   low rating** (the 7 queries where cold top-1 was rating=1). The
+   workers corpus has gaps the v3 slice surfaced.
+3. **Don't ship the "80% generalizes" framing as-is.** The number
+   real_006 measured (82% rank, 68% rating ≥ 2) is the honest one
+   to publish.
+
+This is what reality tests are for. Numbers from the memorized slice
+gave a clean story; numbers from the held-out slice show where it
+needs work.
+
+---
+
+## Repro
+
+```bash
+cd /home/profit/golangLAKEHOUSE
+PATH=/usr/local/go/bin:$PATH go build -o bin/gen_real_queries ./scripts/cutover/gen_real_queries.go
+./bin/gen_real_queries -limit 50 -offset 10 -styles need > tests/reality/real_coord_queries_v3.txt
+
+PATH=/usr/local/go/bin:$PATH \
+  RUN_ID=real_006 \
+  JUDGE_MODEL=qwen2.5:latest \
+  QUERIES_FILE=tests/reality/real_coord_queries_v3.txt \
+  WITH_PARAPHRASE=1 \
+  WITH_REJUDGE=1 \
+  bash scripts/playbook_lift.sh
+```
+
+Local-only. No cloud calls.

scripts/cutover/gen_real_queries.go

@@ -29,6 +29,7 @@ import (
 func main() {
 	src := flag.String("src", "/home/profit/lakehouse/data/datasets/fill_events.parquet", "fill_events parquet path")
 	limit := flag.Int("limit", 10, "number of source rows to read")
+	offset := flag.Int("offset", 0, "skip the first N rows (lets reality tests sample beyond the memorized real_001 slice)")
 	styles := flag.String("styles", "need", "comma-separated styles to emit per row (need|client_first|looking|shorthand|all)")
 	flag.Parse()
 
@@ -58,16 +59,24 @@ func main() {
 	at := tbl.Column(10).Data().Chunk(0)
 	deadline := tbl.Column(12).Data().Chunk(0)
 
-	n := int(tbl.NumRows())
-	if *limit < n {
-		n = *limit
+	totalRows := int(tbl.NumRows())
+	start := *offset
+	if start < 0 {
+		start = 0
+	}
+	if start > totalRows {
+		start = totalRows
+	}
+	end := start + *limit
+	if end > totalRows {
+		end = totalRows
 	}
 
 	stylesList := parseStyles(*styles)
 
 	fmt.Println("# Real-shape coordinator queries — generated from fill_events.parquet")
 	fmt.Println("# (real-shape demand data; queries built mechanically from event rows).")
-	fmt.Printf("# Source: %s (%d rows total, %d emitted, styles=%v)\n", *src, tbl.NumRows(), n, stylesList)
+	fmt.Printf("# Source: %s (%d rows total, rows [%d,%d) emitted, styles=%v)\n", *src, totalRows, start, end, stylesList)
 	fmt.Println("#")
 	fmt.Println("# Styles:")
 	fmt.Println("#   need:         'Need N {role}{s} in {city} {state} starting at {at} for {client}'")
@@ -80,7 +89,7 @@ func main() {
 	fmt.Println("# substrate's bleed behavior when the role gate is silently disabled.")
 	fmt.Println()
 
-	for i := 0; i < n; i++ {
+	for i := start; i < end; i++ {
 		ev := event{
 			client: client.ValueStr(i),
 			city:   city.ValueStr(i),

scripts/cutover/parity/embed_parity.sh

@@ -0,0 +1,137 @@
+#!/usr/bin/env bash
+# embed_parity — verify Rust /ai/embed (now direct Ollama post-sidecar
+# drop) and Go /v1/embed (via embedd) produce equivalent 768-dim
+# vectors for identical input.
+#
+# Why: today's sidecar drop (lakehouse commit ba928b1) changed Rust's
+# embed transport. Go's embedd has always been direct. A drift would
+# break retrieval semantics — same query, different vector → different
+# top-K matches → different staffing recommendations. This probe is
+# the regression gate.
+#
+# Match metric: cosine similarity > 0.99999. Byte-equal comparison
+# isn't realistic — Go represents embeddings as []float32 and Rust
+# as Vec<f64>, so JSON round-trip introduces small float drift. What
+# matters for retrieval correctness is cosine direction, which both
+# runtimes preserve when calling the same Ollama with the same model.
+#
+# Forces both endpoints to use `nomic-embed-text` so the v1-vs-v2-moe
+# default difference doesn't pollute the comparison.
+#
+# Outputs: reports/cutover/gauntlet_2026-05-02/parity/embed_parity.md
+
+set -uo pipefail
+cd "$(dirname "$0")/../../.."
+
+RUST_GW="${RUST_GW:-http://127.0.0.1:3100}"
+GO_GW="${GO_GW:-http://127.0.0.1:4110}"
+MODEL="${EMBED_MODEL:-nomic-embed-text}"
+THRESHOLD="${EMBED_COSINE_THRESHOLD:-0.99999}"
+OUT_DIR="reports/cutover/gauntlet_2026-05-02/parity"
+mkdir -p "$OUT_DIR"
+OUT="$OUT_DIR/embed_parity.md"
+
+# Fixtures cover the staffing-domain text shapes plus stress shapes
+# (unicode, very short, very long).
+FIXTURES=(
+  "forklift operator"
+  "Welder, Toledo OH, 2nd shift"
+  "OSHA-30 certified driver"
+  "dental hygienist with 3 years experience"
+  "CNC machine operator graveyard"
+  "Café résumé ⭐ 你好"
+  "x"
+  "$(printf 'long fixture: %.0s' {1..200})end"
+)
+
+probe() {
+  local gw="$1" path="$2" text="$3"
+  curl -sf -m 15 -X POST "$gw$path" \
+    -H 'Content-Type: application/json' \
+    -d "$(jq -nc --arg t "$text" --arg m "$MODEL" '{texts:[$t], model:$m}')" 2>/dev/null
+}
+
+# Cosine via inline python3 (bash arithmetic doesn't have sqrt).
+cosine() {
+  local rust_json="$1" go_json="$2"
+  python3 - <<EOF
+import json, math, sys
+r = json.loads('''$rust_json''')
+g = json.loads('''$go_json''')
+# Rust /ai/embed returns {embeddings: [[...]]}, dimensions field
+# Go /v1/embed returns {vectors: [[...]]}, dimension field
+rv = r.get("embeddings", r.get("vectors", []))[0]
+gv = g.get("vectors", g.get("embeddings", []))[0]
+if len(rv) != len(gv):
+    print(f"DIM_MISMATCH:rust={len(rv)},go={len(gv)}")
+    sys.exit(0)
+dot = sum(a*b for a,b in zip(rv,gv))
+nr = math.sqrt(sum(a*a for a in rv))
+ng = math.sqrt(sum(b*b for b in gv))
+if nr == 0 or ng == 0:
+    print("ZERO_NORM")
+    sys.exit(0)
+print(f"{dot/(nr*ng):.10f}")
+EOF
+}
+
+TOTAL=0; MATCH=0; DIFF=0
+DIFF_DETAIL=""
+
+for text in "${FIXTURES[@]}"; do
+  TOTAL=$((TOTAL+1))
+  rust_json=$(probe "$RUST_GW" "/ai/embed" "$text")
+  go_json=$(probe "$GO_GW" "/v1/embed" "$text")
+  if [ -z "$rust_json" ] || [ -z "$go_json" ]; then
+    DIFF=$((DIFF+1))
+    label=$(echo "$text" | head -c 60)
+    DIFF_DETAIL="$DIFF_DETAIL"$'\n'"- \`$label\`: helper failed (rust_empty=$([[ -z "$rust_json" ]] && echo y || echo n) go_empty=$([[ -z "$go_json" ]] && echo y || echo n))"
+    continue
+  fi
+  cos=$(cosine "$rust_json" "$go_json")
+  label=$(echo "$text" | head -c 60 | tr '\n' ' ')
+  case "$cos" in
+    DIM_MISMATCH:*|ZERO_NORM)
+      DIFF=$((DIFF+1))
+      DIFF_DETAIL="$DIFF_DETAIL"$'\n'"- \`$label\` → $cos"
+      ;;
+    *)
+      # Compare cos vs threshold via awk (bash can't compare floats).
+      if awk -v c="$cos" -v t="$THRESHOLD" 'BEGIN{exit !(c >= t)}'; then
+        MATCH=$((MATCH+1))
+      else
+        DIFF=$((DIFF+1))
+        DIFF_DETAIL="$DIFF_DETAIL"$'\n'"- \`$label\` → cos=$cos (below threshold $THRESHOLD)"
+      fi
+      ;;
+  esac
+done
+
+{
+  echo "# /v1/embed cross-runtime parity probe"
+  echo
+  echo "**Date:** $(date -u +%Y-%m-%dT%H:%M:%SZ)"
+  echo "**Rust:** \`$RUST_GW/ai/embed\`  ·  **Go:** \`$GO_GW/v1/embed\`"
+  echo "**Model:** \`$MODEL\` (forced — overrides each side's default)"
+  echo "**Match metric:** cosine similarity ≥ \`$THRESHOLD\`"
+  echo
+  echo "Identical text → both endpoints. Cosine compares vector"
+  echo "DIRECTION (the operationally-meaningful property for HNSW"
+  echo "retrieval); byte-equal isn't expected because Go round-trips"
+  echo "through float32 internally while Rust stays at f64."
+  echo
+  echo "**Tally:** $MATCH match · $DIFF diff (out of $TOTAL fixtures)"
+  if [ -n "$DIFF_DETAIL" ]; then
+    echo
+    echo "## Divergences"
+    echo "$DIFF_DETAIL"
+  else
+    echo
+    echo "_Cosine ≥ $THRESHOLD on every fixture — embed parity holds_"
+    echo "_post-sidecar-drop. Rust and Go produce vectors that point in_"
+    echo "_the same direction in 768-dim space._"
+  fi
+} > "$OUT"
+
+echo "[parity] embed: $MATCH match / $DIFF diff (out of $TOTAL) → $OUT"
+[ "$DIFF" -eq 0 ]

scripts/cutover/parity/extract_json_helper/main.go

@@ -0,0 +1,36 @@
+// extract_json_helper — Go-side counterpart to the Rust
+// parity_extract_json binary. Reads stdin, runs
+// validator.ExtractJSON, prints {matched, value} JSON to stdout.
+//
+// Used exclusively by
+// `scripts/cutover/parity/extract_json_parity.sh` to verify
+// cross-runtime equivalence of extract_json across Rust and Go.
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+
+	"git.agentview.dev/profit/golangLAKEHOUSE/internal/validator"
+)
+
+func main() {
+	buf, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "read stdin: %v\n", err)
+		os.Exit(1)
+	}
+	v := validator.ExtractJSON(string(buf))
+	out := map[string]any{
+		"matched": v != nil,
+		"value":   v,
+	}
+	body, err := json.Marshal(out)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "marshal: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Println(string(body))
+}

scripts/cutover/parity/extract_json_parity.sh

@@ -0,0 +1,143 @@
+#!/usr/bin/env bash
+# extract_json_parity — feed identical model-output strings through
+# both Rust extract_json AND Go ExtractJSON; diff outputs.
+#
+# Why: the iteration loop's correctness hinges on extract_json finding
+# the same JSON object in the same model output regardless of runtime.
+# A divergence here means a model output that one runtime accepts and
+# the other rejects (or worse, both accept but parse differently).
+#
+# Approach:
+#   1. Run cargo test -p gateway extract_json to assert the LIVE Rust
+#      function still passes its own unit tests (substrate gate)
+#   2. For each fixture (input, label) tuple:
+#        Rust: ./target/release/parity_extract_json < fixture
+#        Go:   ./bin/parity_extract_json_go < fixture
+#      Compare {matched, value} JSON outputs
+#   3. Emit a markdown report with per-fixture matches/diffs
+#
+# Outputs: reports/cutover/gauntlet_2026-05-02/parity/extract_json_parity.md
+#
+# Env overrides:
+#   RUST_REPO=/home/profit/lakehouse
+#   RUST_BIN=$RUST_REPO/target/release/parity_extract_json
+
+set -uo pipefail
+cd "$(dirname "$0")/../../.."
+
+RUST_REPO="${RUST_REPO:-/home/profit/lakehouse}"
+RUST_BIN="${RUST_BIN:-$RUST_REPO/target/release/parity_extract_json}"
+GO_BIN="${GO_BIN:-./bin/parity_extract_json_go}"
+OUT_DIR="reports/cutover/gauntlet_2026-05-02/parity"
+mkdir -p "$OUT_DIR"
+OUT="$OUT_DIR/extract_json_parity.md"
+
+export PATH="$PATH:/usr/local/go/bin"
+
+# ── Build / verify both sides ───────────────────────────────────────
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[extract-json-parity] building Rust helper..."
+  (cd "$RUST_REPO" && cargo build -p gateway --bin parity_extract_json --release 2>&1 | tail -3)
+fi
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[extract-json-parity] SKIP: $RUST_BIN missing"
+  exit 0
+fi
+
+# Run live Rust unit tests (substrate gate) — ensures our helper
+# matches the production extract_json behavior.
+echo "[extract-json-parity] running cargo test extract_json (substrate gate)..."
+(cd "$RUST_REPO" && cargo test -p gateway --release extract_json 2>&1 | tail -8) > /tmp/rust_extract_test.log
+if ! grep -q "test result: ok" /tmp/rust_extract_test.log; then
+  echo "[extract-json-parity] live Rust tests FAILED — aborting probe"
+  cat /tmp/rust_extract_test.log
+  exit 1
+fi
+echo "  ✓ live Rust extract_json tests PASS"
+
+# Build Go-side helper from internal/validator.ExtractJSON.
+go build -o "$GO_BIN" ./scripts/cutover/parity/extract_json_helper
+
+# ── Fixture set ─────────────────────────────────────────────────────
+# Inline as label||raw pairs. Curated to exercise every documented
+# branch:
+#   - fenced ```json``` block
+#   - fenced unlabeled ``` block
+#   - bare-braces with stray prose
+#   - first-balanced-of-many
+#   - nested object
+#   - unicode in string values
+#   - escaped quotes
+#   - empty object
+#   - top-level array (both runtimes return first inner object)
+#   - no JSON at all
+#   - malformed JSON-shaped text (depth balanced but invalid syntax)
+#   - very-large input (~10KB of prose around a tiny object)
+declare -a FIXTURES=(
+  "fenced_json_block||Here's my answer:
+\`\`\`json
+{\"fills\":[{\"candidate_id\":\"W-1\"}]}
+\`\`\`
+Done."
+  "fenced_unlabeled||result:
+\`\`\`
+{\"k\":\"v\"}
+\`\`\`"
+  "bare_braces||Here you go: {\"fills\":[{\"candidate_id\":\"W-2\"}]}"
+  "first_of_many||{\"a\":1} then {\"b\":2}"
+  "nested||prefix {\"outer\":{\"inner\":[1,2,3]},\"x\":\"y\"} suffix"
+  "unicode||{\"name\":\"Café résumé\",\"emoji\":\"⭐\"}"
+  "escaped_quotes||{\"msg\":\"she said \\\"hello\\\"\"}"
+  "empty_object||{}"
+  "array_of_objects||[{\"a\":1},{\"b\":2}]"
+  "no_json||just prose, no json"
+  "depth_balanced_invalid||{not a key: still not}"
+  "trailing_garbage||{\"k\":\"v\"} and then 5} more } stuff"
+)
+
+TOTAL=0; MATCH=0; DIFF=0
+DIFF_DETAIL=""
+
+for entry in "${FIXTURES[@]}"; do
+  IFS='||' read -r label raw <<<"$entry"
+  TOTAL=$((TOTAL+1))
+  rust_out=$(printf '%s' "$raw" | "$RUST_BIN" 2>/dev/null || echo "RUST_ERROR")
+  go_out=$(printf '%s' "$raw" | "$GO_BIN" 2>/dev/null || echo "GO_ERROR")
+  # Normalize JSON serialization (key order) before comparing.
+  rust_norm=$(echo "$rust_out" | jq -cS . 2>/dev/null || echo "$rust_out")
+  go_norm=$(echo "$go_out" | jq -cS . 2>/dev/null || echo "$go_out")
+  if [ "$rust_norm" = "$go_norm" ]; then
+    MATCH=$((MATCH+1))
+  else
+    DIFF=$((DIFF+1))
+    raw_short=$(printf '%s' "$raw" | head -c 120 | tr '\n' ' ')
+    DIFF_DETAIL="$DIFF_DETAIL"$'\n\n'"### $label"$'\n''**Input (first 120 chars):** `'"$raw_short"'`'$'\n\n''**Rust:**'$'\n''```json'$'\n'"$rust_norm"$'\n''```'$'\n\n''**Go:**'$'\n''```json'$'\n'"$go_norm"$'\n''```'
+  fi
+done
+
+# ── Report ──────────────────────────────────────────────────────────
+{
+  echo "# extract_json parity probe — Rust vs Go"
+  echo
+  echo "**Date:** $(date -u +%Y-%m-%dT%H:%M:%SZ)"
+  echo "**Rust helper:** \`$RUST_BIN\` (links live \`gateway::v1::iterate::extract_json\`)"
+  echo "**Go helper:** \`$GO_BIN\` (links live \`internal/validator.ExtractJSON\`)"
+  echo
+  echo "Identical model-output strings → both runtimes' \`extract_json\`."
+  echo "Match = identical \`{matched, value}\` JSON output."
+  echo
+  echo "**Substrate gate:** \`cargo test -p gateway extract_json\` PASS before probe."
+  echo
+  echo "**Tally:** $MATCH match · $DIFF diff (out of $TOTAL fixtures)"
+  if [ -n "$DIFF_DETAIL" ]; then
+    echo
+    echo "## Divergences"
+    echo "$DIFF_DETAIL"
+  else
+    echo
+    echo "_No divergences — extract_json parity holds across all fixtures._"
+  fi
+} > "$OUT"
+
+echo "[parity] extract_json: $MATCH match / $DIFF diff (out of $TOTAL) → $OUT"
+[ "$DIFF" -eq 0 ]

scripts/cutover/parity/materializer_parity.sh

@@ -0,0 +1,180 @@
+#!/usr/bin/env bash
+# materializer_parity — run Bun + Go materializer against an identical
+# synthetic root, diff the resulting data/evidence/ JSONL files.
+#
+# This validates the parity claim from the 2026-05-02 port: "on-wire
+# JSON shape matches TS so Bun and Go runs are interchangeable." Any
+# divergence here is a finding the architecture comparison should
+# record (precedent: 2026-05-02 validator parity probe surfaced the
+# Rust serde-tagged-enum vs Go flat-struct error envelope gap).
+#
+# Approach:
+#   1. Set up a temp ROOT with a fixed source data/_kb/distilled_facts.jsonl
+#      + observer_escalations.jsonl (small, every transform field exercised)
+#   2. Run Bun materializer:
+#        bun run /home/profit/lakehouse/scripts/distillation/build_evidence_index.ts
+#      against TS-side ROOT (TS expects a real lakehouse repo layout)
+#   3. Run Go materializer:
+#        ./bin/materializer -root <ROOT>
+#      against the same ROOT (after wiping evidence/ between runs)
+#   4. Diff the output JSONL files, normalized for non-deterministic
+#      fields (provenance.recorded_at, ordering).
+#
+# Outputs: reports/cutover/gauntlet_2026-05-02/parity/materializer_parity.md
+#
+# Exit 0 = byte-equal (modulo timestamps); exit non-zero = drift.
+#
+# Env overrides:
+#   RUST_REPO=/home/profit/lakehouse           # Rust legacy repo
+#   GO_BIN=./bin/materializer                  # Go binary (built per-call)
+
+set -uo pipefail
+cd "$(dirname "$0")/../../.."
+
+RUST_REPO="${RUST_REPO:-/home/profit/lakehouse}"
+GO_BIN="${GO_BIN:-./bin/materializer}"
+OUT_DIR="reports/cutover/gauntlet_2026-05-02/parity"
+mkdir -p "$OUT_DIR"
+OUT="$OUT_DIR/materializer_parity.md"
+
+# Build Go materializer fresh.
+export PATH="$PATH:/usr/local/go/bin"
+go build -o "$GO_BIN" ./cmd/materializer
+
+# Locate Bun. Skip with an explicit message if it's missing (CI without bun).
+if ! command -v bun >/dev/null 2>&1; then
+  echo "[materializer-parity] SKIP: bun not on PATH"
+  exit 0
+fi
+
+# Confirm Rust-side materializer is present.
+TS_MAT="$RUST_REPO/scripts/distillation/build_evidence_index.ts"
+if [ ! -f "$TS_MAT" ]; then
+  echo "[materializer-parity] SKIP: $TS_MAT not found"
+  exit 0
+fi
+
+ROOT="$(mktemp -d)"
+trap 'rm -rf "$ROOT"' EXIT INT TERM
+
+mkdir -p "$ROOT/data/_kb"
+# Synthetic distilled_facts — exercises the simplest transform shape.
+cat > "$ROOT/data/_kb/distilled_facts.jsonl" <<EOF
+{"run_id":"r1","source_label":"lab-a","created_at":"2026-04-26T00:00:00Z","extractor":"qwen3.5:latest","text":"first fact"}
+{"run_id":"r2","source_label":"lab-b","created_at":"2026-04-26T01:00:00Z","extractor":"qwen3.5:latest","text":"second fact"}
+{"run_id":"r3","source_label":"lab-c","created_at":"2026-04-26T02:00:00Z","extractor":"qwen2.5:latest","text":"third — different extractor"}
+EOF
+# observer_escalations — exercises the prompt_tokens/completion_tokens
+# fields we added to EvidenceRecord during the materializer port.
+cat > "$ROOT/data/_kb/observer_escalations.jsonl" <<EOF
+{"ts":"2026-04-26T12:00:00Z","sig_hash":"abc123","cluster_endpoint":"/v1/chat","prompt_tokens":150,"completion_tokens":75,"analysis":"escalation review notes"}
+EOF
+
+# Pin recorded_at across BOTH runs so provenance.recorded_at matches.
+PINNED_TS="2026-05-02T00:00:00Z"
+
+# ── Bun run ────────────────────────────────────────────────────────
+# Bun side reads its own root. We have to copy the fixtures under the
+# Bun side's expectation (it defaults to /home/profit/lakehouse), or
+# override via LH_DISTILL_ROOT. But the Bun materializer's CLI reads
+# `new Date().toISOString()` for recorded_at — we can't pin without
+# editing the script. Workaround: capture the full output, then
+# normalize provenance.recorded_at out of both sides for diff.
+BUN_ROOT="$ROOT/bun_side"
+mkdir -p "$BUN_ROOT/data/_kb"
+cp "$ROOT/data/_kb/"* "$BUN_ROOT/data/_kb/"
+
+echo "[materializer-parity] running Bun materializer..."
+LH_DISTILL_ROOT="$BUN_ROOT" bun run "$TS_MAT" \
+  > /tmp/bun_mat.log 2>&1 || {
+    echo "[materializer-parity] bun run failed:"
+    tail -30 /tmp/bun_mat.log
+    exit 1
+  }
+
+# ── Go run ─────────────────────────────────────────────────────────
+GO_ROOT="$ROOT/go_side"
+mkdir -p "$GO_ROOT/data/_kb"
+cp "$ROOT/data/_kb/"* "$GO_ROOT/data/_kb/"
+
+echo "[materializer-parity] running Go materializer..."
+"$GO_BIN" -root "$GO_ROOT" > /tmp/go_mat.log 2>&1 || {
+  echo "[materializer-parity] go run failed:"
+  tail -30 /tmp/go_mat.log
+  exit 1
+}
+
+# ── Find output day-partition ──────────────────────────────────────
+# Both runs use today's UTC date. Look up the partition.
+TODAY="$(date -u +%Y/%m/%d)"
+BUN_OUT="$BUN_ROOT/data/evidence/$TODAY"
+GO_OUT="$GO_ROOT/data/evidence/$TODAY"
+
+if [ ! -d "$BUN_OUT" ]; then
+  echo "[materializer-parity] no Bun output dir: $BUN_OUT"
+  ls -la "$BUN_ROOT/data/evidence" 2>/dev/null || true
+  exit 1
+fi
+if [ ! -d "$GO_OUT" ]; then
+  echo "[materializer-parity] no Go output dir: $GO_OUT"
+  exit 1
+fi
+
+# ── Normalize + diff per source-stem ───────────────────────────────
+# Stripped fields:
+#   provenance.recorded_at    — different per-run wall clock
+#
+# Sorted by sig_hash so dedup ordering can't matter.
+normalize() {
+  jq -c -S 'del(.provenance.recorded_at)' "$1" 2>/dev/null \
+    | sort
+}
+
+TOTAL=0; MATCH=0; DIFF=0
+DIFF_DETAIL=""
+for f in "$BUN_OUT"/*.jsonl; do
+  stem=$(basename "$f" .jsonl)
+  go_f="$GO_OUT/$stem.jsonl"
+  TOTAL=$((TOTAL+1))
+  if [ ! -f "$go_f" ]; then
+    DIFF=$((DIFF+1))
+    DIFF_DETAIL="$DIFF_DETAIL"$'\n'"- $stem: present in Bun, missing in Go"
+    continue
+  fi
+  bun_norm=$(normalize "$f")
+  go_norm=$(normalize "$go_f")
+  if [ "$bun_norm" = "$go_norm" ]; then
+    MATCH=$((MATCH+1))
+  else
+    DIFF=$((DIFF+1))
+    # Capture a small diff for the report.
+    diff_block="$(diff <(echo "$bun_norm") <(echo "$go_norm") | head -40)"
+    DIFF_DETAIL="$DIFF_DETAIL"$'\n\n'"### $stem"$'\n''```diff'$'\n'"$diff_block"$'\n''```'
+  fi
+done
+
+# ── Write report ───────────────────────────────────────────────────
+{
+  echo "# Materializer parity probe — Bun vs Go"
+  echo
+  echo "**Date:** $(date -u +%Y-%m-%dT%H:%M:%SZ)"
+  echo "**Bun:** \`$TS_MAT\`"
+  echo "**Go:**  \`$GO_BIN\`"
+  echo
+  echo "Identical \`data/_kb/\` source → both runtimes' materializer."
+  echo "Match = JSONL byte-equal after normalizing \`provenance.recorded_at\`"
+  echo "(per-run wall clock) + sorted line order (dedup ordering)."
+  echo
+  echo "**Tally:** $MATCH match · $DIFF diff (out of $TOTAL stems)"
+  if [ -n "$DIFF_DETAIL" ]; then
+    echo
+    echo "## Divergences"
+    echo "$DIFF_DETAIL"
+  else
+    echo
+    echo "_No divergences — on-wire JSON parity holds._"
+  fi
+} > "$OUT"
+
+echo "[parity] materializer: $MATCH match / $DIFF diff (out of $TOTAL) → $OUT"
+[ "$DIFF" -eq 0 ]

scripts/cutover/parity/session_log_helper/main.go

@@ -0,0 +1,69 @@
+// session_log_helper — Go-side counterpart for the cross-runtime
+// session-log parity probe. Reads a fixture JSON on stdin, builds a
+// SessionRecord, emits one JSONL row to stdout.
+//
+// Used by scripts/cutover/parity/session_log_parity.sh.
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"git.agentview.dev/profit/golangLAKEHOUSE/internal/validator"
+)
+
+// fixtureInput shape mirrors the Rust helper's accepted shape so both
+// helpers can read the same stdin payload.
+type fixtureInput struct {
+	SessionID        string                       `json:"session_id"`
+	Kind             string                       `json:"kind"`
+	Model            string                       `json:"model"`
+	Provider         string                       `json:"provider"`
+	Prompt           string                       `json:"prompt"`
+	Iterations       int                          `json:"iterations"`
+	MaxIterations    int                          `json:"max_iterations"`
+	FinalVerdict     string                       `json:"final_verdict"`
+	Attempts         []validator.SessionAttemptRecord `json:"attempts"`
+	Artifact         map[string]any               `json:"artifact"`
+	GroundedInRoster *bool                        `json:"grounded_in_roster"`
+	DurationMs       int64                        `json:"duration_ms"`
+}
+
+func main() {
+	buf, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "read stdin: %v\n", err)
+		os.Exit(1)
+	}
+	var in fixtureInput
+	if err := json.Unmarshal(buf, &in); err != nil {
+		fmt.Fprintf(os.Stderr, "parse stdin: %v\n", err)
+		os.Exit(1)
+	}
+	rec := validator.SessionRecord{
+		Schema:           validator.SessionRecordSchema,
+		SessionID:        in.SessionID,
+		Timestamp:        time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC).Format(time.RFC3339),
+		Daemon:           "validatord",
+		Kind:             in.Kind,
+		Model:            in.Model,
+		Provider:         in.Provider,
+		Prompt:           in.Prompt,
+		Iterations:       in.Iterations,
+		MaxIterations:    in.MaxIterations,
+		FinalVerdict:     in.FinalVerdict,
+		Attempts:         in.Attempts,
+		Artifact:         in.Artifact,
+		GroundedInRoster: in.GroundedInRoster,
+		DurationMs:       in.DurationMs,
+	}
+	body, err := json.Marshal(rec)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "marshal: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Println(string(body))
+}

scripts/cutover/parity/session_log_parity.sh

@@ -0,0 +1,127 @@
+#!/usr/bin/env bash
+# session_log_parity — verify Rust gateway and Go validatord write
+# byte-equivalent SessionRecord JSONL rows from identical input.
+#
+# Why: the longitudinal session log (one row per /v1/iterate session)
+# is the offline-analysis layer. Cross-runtime drift means a DuckDB
+# query that works against one log fails against the other — the
+# whole "unified longitudinal view" theory unravels. This probe is
+# the regression gate.
+#
+# Approach (pure schema check, no live daemon needed):
+#   1. Build both runtimes' session_log writers as standalone helper
+#      binaries that take a fixture JSON on stdin and emit one row.
+#   2. Feed identical fixture inputs through each.
+#   3. Diff the resulting rows after normalizing the few fields that
+#      MUST differ (timestamp, daemon).
+#
+# Outputs: reports/cutover/gauntlet_2026-05-02/parity/session_log_parity.md
+#
+# Exit 0 on schema match; exit 1 on drift.
+
+set -uo pipefail
+cd "$(dirname "$0")/../../.."
+
+RUST_REPO="${RUST_REPO:-/home/profit/lakehouse}"
+RUST_BIN="${RUST_BIN:-$RUST_REPO/target/release/parity_session_log}"
+GO_BIN="${GO_BIN:-./bin/parity_session_log_go}"
+OUT_DIR="reports/cutover/gauntlet_2026-05-02/parity"
+mkdir -p "$OUT_DIR"
+OUT="$OUT_DIR/session_log_parity.md"
+
+export PATH="$PATH:/usr/local/go/bin"
+
+# ── Build both helpers ─────────────────────────────────────────────
+go build -o "$GO_BIN" ./scripts/cutover/parity/session_log_helper
+
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[session-log-parity] building Rust helper..."
+  (cd "$RUST_REPO" && cargo build -p gateway --bin parity_session_log --release 2>&1 | tail -3)
+fi
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[session-log-parity] SKIP: $RUST_BIN missing"
+  exit 0
+fi
+
+# ── Fixtures ───────────────────────────────────────────────────────
+# Parallel arrays — labels and fixtures keyed by index. Avoids a
+# separator-in-string scheme (the prior `||` form silently injected
+# a `|` character into every fixture body, which both helpers then
+# rejected with empty output → trivially-equal "match" — caught
+# during initial probe authoring 2026-05-02).
+LABELS=(
+  "accepted_grounded"
+  "max_iter_exhausted"
+  "infra_error"
+  "unicode_in_prompt"
+)
+FIXTURES=(
+  '{"session_id":"trace-1","kind":"fill","model":"qwen3.5:latest","provider":"ollama","prompt":"produce a fill","iterations":1,"max_iterations":3,"final_verdict":"accepted","attempts":[{"iteration":0,"verdict_kind":"accepted","span_id":"sp-0"}],"artifact":{"fills":[{"candidate_id":"W-1"}]},"grounded_in_roster":true,"duration_ms":50}'
+  '{"session_id":"trace-2","kind":"fill","model":"qwen3.5:latest","provider":"ollama","prompt":"P","iterations":3,"max_iterations":3,"final_verdict":"max_iter_exhausted","attempts":[{"iteration":0,"verdict_kind":"validation_failed","error":"phantom W-X","span_id":"sp-a"},{"iteration":1,"verdict_kind":"validation_failed","error":"phantom W-Y","span_id":"sp-b"},{"iteration":2,"verdict_kind":"no_json","span_id":"sp-c"}],"duration_ms":3200}'
+  '{"session_id":"trace-3","kind":"playbook","model":"qwen","provider":"ollama","prompt":"P","iterations":0,"max_iterations":3,"final_verdict":"infra_error","attempts":[{"iteration":0,"verdict_kind":"infra_error","error":"connection refused"}],"duration_ms":12}'
+  '{"session_id":"trace-4","kind":"playbook","model":"qwen","provider":"ollama","prompt":"Café résumé ⭐ 你好","iterations":1,"max_iterations":3,"final_verdict":"accepted","attempts":[{"iteration":0,"verdict_kind":"accepted","span_id":"sp-u"}],"artifact":{"endorsed_names":["W-1"],"operation":"fill: X x1 in A, B","fingerprint":"abc"},"duration_ms":80}'
+)
+
+normalize() {
+  # Strip the few fields that MUST differ between Rust+Go runs
+  # (timestamp = now; daemon = producer name). Sort the keys so the
+  # JSON serialization order doesn't break a byte-equal diff.
+  jq -cS 'del(.timestamp) | del(.daemon)' <<<"$1"
+}
+
+TOTAL=0; MATCH=0; DIFF=0
+DIFF_DETAIL=""
+
+for i in "${!FIXTURES[@]}"; do
+  label="${LABELS[$i]}"
+  fixture="${FIXTURES[$i]}"
+  TOTAL=$((TOTAL+1))
+  rust_row=$(printf '%s' "$fixture" | "$RUST_BIN" 2>&1 || echo '{"error":"rust_helper_failed"}')
+  go_row=$(printf '%s' "$fixture" | "$GO_BIN" 2>&1 || echo '{"error":"go_helper_failed"}')
+  # Refuse trivial-equal-empty matches: if either side produced no
+  # parseable JSON at all, mark this as a diff rather than a match.
+  if ! echo "$rust_row" | jq -e . >/dev/null 2>&1; then
+    rust_norm="<rust helper failed: $(echo "$rust_row" | head -c 200)>"
+  else
+    rust_norm=$(normalize "$rust_row")
+  fi
+  if ! echo "$go_row" | jq -e . >/dev/null 2>&1; then
+    go_norm="<go helper failed: $(echo "$go_row" | head -c 200)>"
+  else
+    go_norm=$(normalize "$go_row")
+  fi
+  if [ "$rust_norm" = "$go_norm" ]; then
+    MATCH=$((MATCH+1))
+  else
+    DIFF=$((DIFF+1))
+    DIFF_DETAIL="$DIFF_DETAIL"$'\n\n'"### $label"$'\n\n''**Rust:**'$'\n''```json'$'\n'"$rust_norm"$'\n''```'$'\n\n''**Go:**'$'\n''```json'$'\n'"$go_norm"$'\n''```'
+  fi
+done
+
+# ── Report ─────────────────────────────────────────────────────────
+{
+  echo "# session_log parity probe — Rust gateway vs Go validatord"
+  echo
+  echo "**Date:** $(date -u +%Y-%m-%dT%H:%M:%SZ)"
+  echo "**Rust helper:** \`$RUST_BIN\`"
+  echo "**Go helper:** \`$GO_BIN\`"
+  echo
+  echo "Identical fixture inputs through each runtime's"
+  echo "\`SessionRecord\` builder + JSON marshaler. Match = byte-equal"
+  echo "after stripping \`timestamp\` (per-run wall clock) + \`daemon\`"
+  echo "(\"gateway\" on Rust side, \"validatord\" on Go side; both are"
+  echo "valid producers in the same longitudinal log)."
+  echo
+  echo "**Tally:** $MATCH match · $DIFF diff (out of $TOTAL fixtures)"
+  if [ -n "$DIFF_DETAIL" ]; then
+    echo
+    echo "## Divergences"
+    echo "$DIFF_DETAIL"
+  else
+    echo
+    echo "_No divergences — schema parity holds across all fixtures._"
+  fi
+} > "$OUT"
+
+echo "[parity] session_log: $MATCH match / $DIFF diff (out of $TOTAL) → $OUT"
+[ "$DIFF" -eq 0 ]

scripts/cutover/parity/subject_audit_helper/main.go

@@ -0,0 +1,168 @@
+// Cross-runtime parity helper — Go side.
+//
+// Specification: /home/profit/lakehouse/docs/specs/SUBJECT_MANIFESTS_ON_CATALOGD.md §5 Step 8.
+//
+// Counterpart of crates/catalogd/src/bin/parity_subject_audit.rs.
+// Both helpers MUST produce byte-identical output for the same input.
+//
+// Modes:
+//
+//   --known-answer
+//       Print canonical-JSON + HMAC for a hardcoded fixture. Compared
+//       byte-for-byte against the Rust helper's output. If they
+//       differ, the canonical-JSON or HMAC algorithm has drifted.
+//
+//   --verify <audit_log_path> --key <key_path>
+//       Replay the HMAC chain on a real audit JSONL. Print one JSON
+//       object: {mode, count, tip, verified, error}.
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	cat "git.agentview.dev/profit/golangLAKEHOUSE/internal/catalogd"
+)
+
+const genesis = "GENESIS"
+
+func deterministicKey() []byte {
+	k := make([]byte, 32)
+	for i := range k {
+		k[i] = byte(i)
+	}
+	return k
+}
+
+// knownAnswerOut is intentionally identical to KnownAnswerOut in the
+// Rust helper so a stdout diff is a one-line semantic comparison.
+type knownAnswerOut struct {
+	Mode              string `json:"mode"`
+	Canonical         string `json:"canonical"`
+	Hmac              string `json:"hmac"`
+	CanonicalBytesLen int    `json:"canonical_bytes_len"`
+}
+
+type verifyOut struct {
+	Mode     string `json:"mode"`
+	Count    int    `json:"count"`
+	Tip      string `json:"tip"`
+	Verified bool   `json:"verified"`
+	Error    *string `json:"error"`
+}
+
+func runKnownAnswer() {
+	row := cat.SubjectAuditRow{
+		Schema:      "subject_audit.v1",
+		Ts:          time.Date(2026, 5, 3, 12, 0, 0, 0, time.UTC),
+		CandidateID: "WORKER-FIXED",
+		Accessor: cat.AuditAccessor{
+			Kind:    "gateway_lookup",
+			Daemon:  "gateway",
+			Purpose: "parity_test",
+			TraceID: "trace-fixed",
+		},
+		FieldsAccessed: []string{"name"},
+		Result:         "success",
+		PrevChainHash:  genesis,
+	}
+	canonical, hmacHex, err := cat.CanonicalAndHmac(&row, deterministicKey(), genesis)
+	if err != nil {
+		die("canonical/hmac: %v", err)
+	}
+	out := knownAnswerOut{
+		Mode:              "known_answer",
+		Canonical:         string(canonical),
+		Hmac:              hmacHex,
+		CanonicalBytesLen: len(canonical),
+	}
+	emit(out)
+}
+
+func runVerify(auditPath, keyPath string) {
+	entries, err := cat.ReadAuditLog(auditPath)
+	if err != nil {
+		die("read audit log: %v", err)
+	}
+	key, err := os.ReadFile(keyPath)
+	if err != nil {
+		die("read key: %v", err)
+	}
+	count, tip, verr := cat.VerifyChain(entries, key)
+	out := verifyOut{
+		Mode:     "verify",
+		Count:    count,
+		Tip:      tip,
+		Verified: verr == nil,
+	}
+	if verr != nil {
+		s := verr.Error()
+		out.Error = &s
+		// Reset count + tip to match the Rust helper's error semantics.
+		out.Count = 0
+		out.Tip = genesis
+	}
+	emit(out)
+}
+
+func emit(v any) {
+	bs, err := json.Marshal(v)
+	if err != nil {
+		die("marshal output: %v", err)
+	}
+	fmt.Println(string(bs))
+}
+
+func die(format string, a ...any) {
+	fmt.Fprintf(os.Stderr, format+"\n", a...)
+	os.Exit(2)
+}
+
+func main() {
+	args := os.Args[1:]
+	var (
+		knownAnswer bool
+		auditPath   string
+		keyPath     string
+	)
+	for i := 0; i < len(args); i++ {
+		switch args[i] {
+		case "--known-answer":
+			knownAnswer = true
+		case "--verify":
+			if i+1 >= len(args) {
+				die("--verify needs a path")
+			}
+			auditPath = args[i+1]
+			i++
+		case "--key":
+			if i+1 >= len(args) {
+				die("--key needs a path")
+			}
+			keyPath = args[i+1]
+			i++
+		case "-h", "--help":
+			fmt.Fprintln(os.Stderr, "subject_audit_helper --known-answer")
+			fmt.Fprintln(os.Stderr, "subject_audit_helper --verify <audit_log> --key <key_file>")
+			os.Exit(0)
+		default:
+			die("unknown arg: %s", args[i])
+		}
+	}
+	if knownAnswer {
+		runKnownAnswer()
+		return
+	}
+	if auditPath == "" || keyPath == "" {
+		die("need --known-answer OR (--verify <path> --key <path>)")
+	}
+	// Sanity: file naming convention <candidate_id>.audit.jsonl.
+	if !strings.HasSuffix(filepath.Base(auditPath), ".audit.jsonl") {
+		die("audit log path must end with .audit.jsonl")
+	}
+	runVerify(auditPath, keyPath)
+}

scripts/cutover/parity/subject_audit_parity.sh

@@ -0,0 +1,203 @@
+#!/usr/bin/env bash
+# subject_audit_parity — verify Rust and Go produce byte-identical
+# canonical JSON + HMAC-SHA256 chain hashes for subject audit logs.
+#
+# Why: the SubjectManifest + audit-log substrate (Rust crates/catalogd
+# subject_audit.rs) is consumed by the legal-tier endpoint /audit/subject/{id}
+# AND by the Go internal/catalogd reader. A canonical-JSON drift between
+# the two runtimes would mean a chain written by Rust does not verify
+# under Go (or worse, verifies as tampered) — silently breaking the
+# defensible-audit guarantee.
+#
+# The probe runs in two phases:
+#
+#   Phase 1 — Known-answer vector
+#     Both helpers serialize the same hardcoded SubjectAuditRow,
+#     emit canonical bytes + HMAC. Outputs MUST be byte-identical.
+#     This catches algorithm drift independent of any real data.
+#
+#   Phase 2 — Real production audit logs
+#     Walk every *.audit.jsonl in the live data dir. Run BOTH helpers
+#     against each one with the production signing key. Outputs MUST
+#     be byte-identical. This catches real-world drift (e.g. struct
+#     field tag mismatches that only fire on certain field values).
+#
+# Outputs: reports/cutover/gauntlet_2026-05-02/parity/subject_audit_parity.md
+#
+# Env overrides:
+#   RUST_REPO=/home/profit/lakehouse
+#   RUST_BIN=$RUST_REPO/target/release/parity_subject_audit
+#   GO_BIN=./bin/subject_audit_helper
+#   AUDIT_DIR=$RUST_REPO/data/_catalog/subjects
+#   KEY_PATH=/tmp/lakehouse_audit/subject_audit.key
+
+set -uo pipefail
+cd "$(dirname "$0")/../../.."
+
+RUST_REPO="${RUST_REPO:-/home/profit/lakehouse}"
+RUST_BIN="${RUST_BIN:-$RUST_REPO/target/release/parity_subject_audit}"
+GO_BIN="${GO_BIN:-./bin/subject_audit_helper}"
+AUDIT_DIR="${AUDIT_DIR:-$RUST_REPO/data/_catalog/subjects}"
+KEY_PATH="${KEY_PATH:-/tmp/lakehouse_audit/subject_audit.key}"
+
+OUT_DIR="reports/cutover/gauntlet_2026-05-02/parity"
+mkdir -p "$OUT_DIR"
+OUT="$OUT_DIR/subject_audit_parity.md"
+
+export PATH="$PATH:/usr/local/go/bin"
+
+# ── Build / verify both sides ───────────────────────────────────────
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[subject-audit-parity] building Rust helper..."
+  (cd "$RUST_REPO" && cargo build -p catalogd --bin parity_subject_audit --release 2>&1 | tail -3)
+fi
+if [ ! -x "$RUST_BIN" ]; then
+  echo "[subject-audit-parity] SKIP: $RUST_BIN missing"
+  exit 0
+fi
+
+if [ ! -x "$GO_BIN" ]; then
+  echo "[subject-audit-parity] building Go helper..."
+  go build -o "$GO_BIN" ./scripts/cutover/parity/subject_audit_helper/
+fi
+if [ ! -x "$GO_BIN" ]; then
+  echo "[subject-audit-parity] FAIL: $GO_BIN missing after build"
+  exit 1
+fi
+
+# ── Report header ───────────────────────────────────────────────────
+{
+  echo "# subject_audit_parity"
+  echo
+  echo "**Generated:** $(date -u '+%Y-%m-%d %H:%M:%S UTC')"
+  echo "**Spec:** /home/profit/lakehouse/docs/specs/SUBJECT_MANIFESTS_ON_CATALOGD.md §5 Step 8"
+  echo "**Rust helper:** \`$RUST_BIN\`"
+  echo "**Go helper:** \`$GO_BIN\`"
+  echo "**Audit dir:** \`$AUDIT_DIR\`"
+  echo
+} > "$OUT"
+
+PASS=0
+FAIL=0
+
+# ── Phase 1 — Known-answer vector ───────────────────────────────────
+{
+  echo "## Phase 1 — Known-answer vector"
+  echo
+  echo "Hardcoded fixture row, identical inputs, byte-compare canonical-JSON + HMAC."
+  echo
+} >> "$OUT"
+
+RUST_KA="$(mktemp)"; GO_KA="$(mktemp)"
+"$RUST_BIN" --known-answer > "$RUST_KA" 2>&1 || true
+"$GO_BIN" --known-answer > "$GO_KA" 2>&1 || true
+
+if diff -q "$RUST_KA" "$GO_KA" >/dev/null 2>&1; then
+  PASS=$((PASS+1))
+  {
+    echo "**MATCH** ✓"
+    echo
+    echo '```json'
+    cat "$RUST_KA"
+    echo '```'
+    echo
+  } >> "$OUT"
+else
+  FAIL=$((FAIL+1))
+  {
+    echo "**MISMATCH** ✗"
+    echo
+    echo "### Rust"
+    echo '```json'
+    cat "$RUST_KA"
+    echo '```'
+    echo
+    echo "### Go"
+    echo '```json'
+    cat "$GO_KA"
+    echo '```'
+    echo
+    echo "### Diff"
+    echo '```diff'
+    diff "$RUST_KA" "$GO_KA" || true
+    echo '```'
+    echo
+  } >> "$OUT"
+fi
+
+# ── Phase 2 — Real production audit logs ────────────────────────────
+{
+  echo "## Phase 2 — Real production audit logs"
+  echo
+  echo "Every \`*.audit.jsonl\` in \`$AUDIT_DIR\` verified by both runtimes."
+  echo
+} >> "$OUT"
+
+if [ ! -r "$KEY_PATH" ]; then
+  {
+    echo "**SKIP** — signing key not readable at \`$KEY_PATH\`."
+    echo "Set \`KEY_PATH=...\` or seed /tmp/lakehouse_audit/subject_audit.key (see systemd unit)."
+    echo
+  } >> "$OUT"
+else
+  shopt -s nullglob
+  LOGS=( "$AUDIT_DIR"/*.audit.jsonl )
+  if [ "${#LOGS[@]}" -eq 0 ]; then
+    {
+      echo "**SKIP** — no \`*.audit.jsonl\` files under \`$AUDIT_DIR\`."
+      echo "(Trigger one by hitting the gateway with /v1/validate on a candidate_id.)"
+      echo
+    } >> "$OUT"
+  else
+    {
+      echo "| Audit log | Rust verified | Go verified | Result |"
+      echo "|---|---|---|---|"
+    } >> "$OUT"
+    for log in "${LOGS[@]}"; do
+      label="$(basename "$log")"
+      RUST_OUT="$(mktemp)"; GO_OUT="$(mktemp)"
+      "$RUST_BIN" --verify "$log" --key "$KEY_PATH" > "$RUST_OUT" 2>&1 || true
+      "$GO_BIN" --verify "$log" --key "$KEY_PATH" > "$GO_OUT" 2>&1 || true
+      rust_count=$(jq -r '.count // 0' < "$RUST_OUT" 2>/dev/null || echo "?")
+      go_count=$(jq -r '.count // 0' < "$GO_OUT" 2>/dev/null || echo "?")
+      rust_ok=$(jq -r '.verified // false' < "$RUST_OUT" 2>/dev/null || echo "?")
+      go_ok=$(jq -r '.verified // false' < "$GO_OUT" 2>/dev/null || echo "?")
+      if diff -q "$RUST_OUT" "$GO_OUT" >/dev/null 2>&1; then
+        PASS=$((PASS+1))
+        echo "| \`$label\` | $rust_count rows ($rust_ok) | $go_count rows ($go_ok) | **MATCH** ✓ |" >> "$OUT"
+      else
+        FAIL=$((FAIL+1))
+        {
+          echo "| \`$label\` | $rust_count rows ($rust_ok) | $go_count rows ($go_ok) | **MISMATCH** ✗ |"
+          echo
+          echo "### Diff for \`$label\`"
+          echo '```diff'
+          diff "$RUST_OUT" "$GO_OUT" || true
+          echo '```'
+          echo
+        } >> "$OUT"
+      fi
+      rm -f "$RUST_OUT" "$GO_OUT"
+    done
+  fi
+fi
+rm -f "$RUST_KA" "$GO_KA"
+
+# ── Summary ─────────────────────────────────────────────────────────
+TOTAL=$((PASS + FAIL))
+{
+  echo
+  echo "## Summary"
+  echo
+  echo "**$PASS / $TOTAL** parity assertions passed."
+  echo
+  if [ "$FAIL" -gt 0 ]; then
+    echo "**Status: DIVERGED** — Rust and Go disagree on at least one canonical-JSON or HMAC computation."
+    echo "Investigate the diff above before declaring cross-runtime parity."
+  else
+    echo "**Status: PARITY** — every Rust assertion matches Go byte-for-byte."
+  fi
+} >> "$OUT"
+
+echo "[subject-audit-parity] $PASS / $TOTAL pass — report: $OUT"
+[ "$FAIL" -eq 0 ]

scripts/cutover/start_go_stack.sh

@@ -135,32 +135,47 @@ start observerd 4219
 start matrixd   4218
 start gateway   4110
 
-# chatd is started independently — its provider key files come from
-# /etc/lakehouse/{ollama_cloud,openrouter,opencode,kimi}.env; if
-# chatd is already up (long-running from a prior session) we don't
-# touch it. chatd uses no S3, so no temp-toml override needed.
-if ! curl -sSf -m 1 http://127.0.0.1:3220/health >/dev/null 2>&1; then
-  echo "[gostack] chatd :3220 not up; starting"
-  nohup ./bin/chatd -config lakehouse.toml > /tmp/gostack-logs/chatd.log 2>&1 & disown
+# chatd + validatord are started independently — both sit OUTSIDE
+# the persistent :4xxx range and are SHARED with smoke harnesses
+# (no bucket / port conflict because chatd has no S3 state and
+# validatord's state is JSONL files, not MinIO). Provider key files
+# come from /etc/lakehouse/{ollama_cloud,openrouter,opencode,kimi}.env.
+# If either is already up (long-running from a prior session) we
+# don't touch it. The matching smokes (chatd_smoke / validatord_smoke)
+# do `pkill -f "bin/<name>$"` on teardown — re-running this script
+# brings them back. No temp-toml override needed for either.
+start_shared() {
+  local bin="$1"
+  local port="$2"
+  if curl -sSf -m 1 "http://127.0.0.1:$port/health" >/dev/null 2>&1; then
+    echo "  $bin :$port already up (skipping)"
+    return 0
+  fi
+  echo "[gostack] $bin :$port not up; starting"
+  nohup ./bin/"$bin" -config lakehouse.toml > "/tmp/gostack-logs/$bin.log" 2>&1 & disown
   for _ in $(seq 1 50); do
-    if curl -sSf -m 1 "http://127.0.0.1:3220/health" >/dev/null 2>&1; then
-      echo "  chatd :3220 up"
-      break
+    if curl -sSf -m 1 "http://127.0.0.1:$port/health" >/dev/null 2>&1; then
+      echo "  $bin :$port up"
+      return 0
     fi
     sleep 0.1
   done
-else
-  echo "  chatd :3220 already up (skipping)"
-fi
+  echo "  $bin :$port FAILED — log tail:"
+  tail -20 "/tmp/gostack-logs/$bin.log"
+  return 1
+}
+
+start_shared chatd      3220
+start_shared validatord 3221
 
 echo
 echo "[gostack] ready · sweep:"
-for p in 4110 4211 4212 4213 4214 4215 4216 4217 4218 4219 3220; do
+for p in 4110 4211 4212 4213 4214 4215 4216 4217 4218 4219 3220 3221; do
   curl -sSf -m 1 "http://127.0.0.1:$p/health" 2>/dev/null | head -c 80
   echo
 done
 echo
 echo "[gostack] persistent stack: ports :4110+:4211-:4219 · bucket=$PERSISTENT_BUCKET"
 echo "[gostack] smoke harnesses:  ports :3110+:3211-:3219 · bucket=lakehouse-go-primary"
-echo "[gostack] shared:           chatd at :3220 (read-mostly LLM dispatch)"
+echo "[gostack] shared:           chatd :3220 + validatord :3221 (no S3 / JSONL-only state)"
 echo "[gostack] tear down via: pkill -f 'bin/persistent-'"

scripts/validatord_smoke.sh

@@ -70,6 +70,7 @@ roster_path = "$ROSTER"
 default_max_iterations = 3
 default_max_tokens     = 4096
 chat_timeout_secs      = 240
+session_log_path       = "$TMP/sessions.jsonl"
 EOF
 
 poll_health() {
@@ -115,13 +116,15 @@ if [ "$STATUS" != "422" ]; then
   echo "  ✗ expected 422; got $STATUS body=$(cat /tmp/playbook_422.json)"
   exit 1
 fi
-KIND="$(jq -r '.Kind' /tmp/playbook_422.json)"
-FIELD="$(jq -r '.Field' /tmp/playbook_422.json)"
-if [ "$KIND" != "schema" ] || [ "$FIELD" != "fingerprint" ]; then
-  echo "  ✗ expected kind=schema field=fingerprint; got kind=$KIND field=$FIELD"
+# Rust serde-tagged-enum shape (parity with crates/validator):
+#   {"Schema":{"field":"fingerprint","reason":"..."}}
+VARIANT="$(jq -r 'keys[0]' /tmp/playbook_422.json)"
+FIELD="$(jq -r '.Schema.field' /tmp/playbook_422.json)"
+if [ "$VARIANT" != "Schema" ] || [ "$FIELD" != "fingerprint" ]; then
+  echo "  ✗ expected variant=Schema field=fingerprint; got variant=$VARIANT field=$FIELD"
   exit 1
 fi
-echo "  ✓ playbook missing fingerprint → 422 schema/fingerprint"
+echo "  ✓ playbook missing fingerprint → 422 Schema/fingerprint"
 
 # 4. /v1/validate fill with phantom candidate → 422 Consistency
 echo "[validatord-smoke] /v1/validate fill with phantom candidate → 422:"
@@ -132,12 +135,13 @@ if [ "$STATUS" != "422" ]; then
   echo "  ✗ expected 422; got $STATUS body=$(cat /tmp/fill_422.json)"
   exit 1
 fi
-KIND="$(jq -r '.Kind' /tmp/fill_422.json)"
-if [ "$KIND" != "consistency" ]; then
-  echo "  ✗ expected kind=consistency; got kind=$KIND body=$(cat /tmp/fill_422.json)"
+# Rust serde-tagged-enum shape: {"Consistency":{"reason":"..."}}
+VARIANT="$(jq -r 'keys[0]' /tmp/fill_422.json)"
+if [ "$VARIANT" != "Consistency" ]; then
+  echo "  ✗ expected variant=Consistency; got variant=$VARIANT body=$(cat /tmp/fill_422.json)"
   exit 1
 fi
-echo "  ✓ phantom candidate W-PHANTOM → 422 consistency"
+echo "  ✓ phantom candidate W-PHANTOM → 422 Consistency"
 
 # 5. /v1/validate unknown kind → 400
 echo "[validatord-smoke] /v1/validate unknown kind → 400:"
@@ -150,4 +154,18 @@ if [ "$STATUS" != "400" ]; then
 fi
 echo "  ✓ unknown kind → 400"
 
-echo "[validatord-smoke] PASS — 5/5 probes through gateway :3110"
+# 6. Session log: every /v1/validate hit was a single-shot validation
+#    (not iterate), so the session log isn't populated yet. Verify it
+#    exists as a path (logger initialized) — the iterate handler is
+#    where rows actually land. This proves the wiring is in place
+#    even if the smoke doesn't drive a live iteration end-to-end.
+LOG_PATH="$TMP/sessions.jsonl"
+echo "[validatord-smoke] session log path wired:"
+grep -q "validatord session log" /tmp/validatord.log || {
+  echo "  ✗ expected validatord to log 'validatord session log' on startup"
+  grep validatord /tmp/validatord.log
+  exit 1
+}
+echo "  ✓ session_log_path=$LOG_PATH announced at startup (rows land on /v1/iterate calls)"
+
+echo "[validatord-smoke] PASS — 6/6 probes through gateway :3110"

tests/reality/real_coord_queries_v3.txt

@@ -0,0 +1,64 @@
+# Real-shape coordinator queries — generated from fill_events.parquet
+# (real-shape demand data; queries built mechanically from event rows).
+# Source: /home/profit/lakehouse/data/datasets/fill_events.parquet (123 rows total, rows [10,60) emitted, styles=[need])
+#
+# Styles:
+#   need:         'Need N {role}{s} in {city} {state} starting at {at} for {client}'
+#                 — matches scripts/playbook_lift's extractRoleFromNeed regex
+#   client_first: '{client} needs N {role}{s} in {city} {state} at {at}'
+#   looking:      'Looking for N {role}{s} at {client} in {city} {state} for {at} shift'
+#   shorthand:    'N {role}{s} {city} {state} {at} {client}'
+#
+# Only 'need' currently extracts a role. The other three test the
+# substrate's bleed behavior when the role gate is silently disabled.
+
+Need 1 Loader in Kansas City MO starting at 17:30 for Cornerstone Fabrication
+Need 2 Assemblers in Cincinnati OH starting at 14:30 for Great Lakes Mfg
+Need 1 Forklift Operator in Lexington KY starting at 08:30 for Vanguard Components, deadline 2026-05-20
+Need 2 Assemblers in Flint MI starting at 08:30 for Centennial Packaging
+Need 2 Welders in Indianapolis IN starting at 10:00 for Northland Logistics
+Need 2 Material Handlers in Cincinnati OH starting at 13:00 for Great Lakes Mfg
+Need 3 Pickers in Flint MI starting at 17:00 for Centennial Packaging
+Need 3 Packers in Indianapolis IN starting at 09:00 for Heritage Foods, deadline 2026-05-04
+Need 3 Assemblers in Columbus OH starting at 17:30 for Riverfront Steel
+Need 5 Machine Operators in Cleveland OH starting at 14:30 for Apex Warehouse
+Need 2 Assemblers in Grand Rapids MI starting at 13:00 for Cornerstone Fabrication, deadline 2026-05-21
+Need 2 Pickers in Akron OH starting at 10:30 for Summit Industrial
+Need 3 Quality Techs in Lexington KY starting at 12:30 for Keystone Plastics, deadline 2026-06-14
+Need 4 Assemblers in Gary IN starting at 12:00 for Heritage Foods
+Need 3 Packers in Toledo OH starting at 16:00 for Cornerstone Fabrication, deadline 2026-06-02
+Need 4 Warehouse Associates in Fort Wayne IN starting at 13:00 for Cornerstone Fabrication, deadline 2026-05-17
+Need 4 Assemblers in Columbus OH starting at 13:00 for Midway Distribution
+Need 2 Shipping Clerks in Chicago IL starting at 17:00 for Midway Distribution
+Need 2 Machine Operators in Chicago IL starting at 11:00 for Midway Distribution
+Need 3 CNC Operators in Grand Rapids MI starting at 10:00 for Parallel Machining, deadline 2026-06-14
+Need 1 Warehouse Associate in Lexington KY starting at 09:30 for Keystone Plastics, deadline 2026-06-14
+Need 2 Material Handlers in Gary IN starting at 11:00 for Heritage Foods
+Need 5 Assemblers in Fort Wayne IN starting at 16:30 for Midway Distribution, deadline 2026-06-09
+Need 1 Loader in Cincinnati OH starting at 08:00 for Summit Industrial
+Need 3 Quality Techs in Columbus OH starting at 12:00 for Riverfront Steel
+Need 1 Machine Operator in Columbus OH starting at 09:30 for Riverfront Steel
+Need 3 Machine Operators in Madison WI starting at 12:00 for Great Lakes Mfg, deadline 2026-05-24
+Need 2 Material Handlers in Kansas City MO starting at 11:30 for Parallel Machining
+Need 3 Loaders in Flint MI starting at 16:00 for Parallel Machining
+Need 2 Welders in Louisville KY starting at 13:00 for Horizon Supply, deadline 2026-06-04
+Need 1 CNC Operator in Flint MI starting at 10:30 for Horizon Supply
+Need 1 Material Handler in Columbus OH starting at 15:30 for Riverfront Steel
+Need 2 Forklift Operators in Louisville KY starting at 14:30 for Cornerstone Fabrication, deadline 2026-06-08
+Need 2 Warehouse Associates in Chicago IL starting at 10:00 for Northland Logistics
+Need 2 Material Handlers in Gary IN starting at 15:00 for Parallel Machining
+Need 1 Forklift Operator in Grand Rapids MI starting at 10:00 for Cornerstone Fabrication, deadline 2026-05-21
+Need 2 Pickers in Louisville KY starting at 12:30 for Cornerstone Fabrication, deadline 2026-06-08
+Need 2 Loaders in Indianapolis IN starting at 17:30 for Midway Distribution
+Need 1 Shipping Clerk in Indianapolis IN starting at 12:30 for Northland Logistics
+Need 2 Assemblers in Cincinnati OH starting at 08:00 for Keystone Plastics, deadline 2026-05-26
+Need 5 Quality Techs in Kansas City MO starting at 11:30 for Summit Industrial, deadline 2026-05-23
+Need 2 Machine Operators in Gary IN starting at 10:00 for Heritage Foods
+Need 1 Packer in Chicago IL starting at 09:30 for Midway Distribution
+Need 2 Pickers in Lexington KY starting at 17:30 for Vanguard Components, deadline 2026-05-20
+Need 2 Maintenance Techs in Grand Rapids MI starting at 17:00 for Pioneer Assembly, deadline 2026-05-20
+Need 1 Material Handler in Detroit MI starting at 10:30 for Summit Industrial
+Need 1 Welder in Akron OH starting at 15:00 for Summit Industrial
+Need 1 Shipping Clerk in Cincinnati OH starting at 13:30 for Summit Industrial
+Need 5 Packers in Indianapolis IN starting at 10:30 for Midway Distribution
+Need 1 Forklift Operator in Louisville KY starting at 10:30 for Cornerstone Fabrication, deadline 2026-06-08