feat(orchestrator): wire turn-decision endpoint and QuotaReported producer

Closes Phase 2 items 1-2 (AUDIT.md): Coordinator.TurnDecision evaluates
occupancy/turn-boundary/handoff state synchronously per turn and returns
continue/prepare_handoff/rotate_now/refuse, exposed via POST
/v1/harness/turn. The Claude Stop hook now calls it on ordinary turn
boundaries instead of no-op'ing, and exits 2 on refuse.

Also closes B7's post-hoc producer: /v1/harness/complete now appends a
QuotaReported event from the completing lease's harness usage, so the
router's quota-availability filter and the brief's quota_consumed stop
evaluating against a permanent zero. Live per-harness push producers
(Claude statusline, Codex rollout tail) remain unbuilt — investigation
recorded in AUDIT.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01W1rkJ2hBMybnJctPbcy4tT

AUDIT.md

@@ -760,3 +760,95 @@ whether Codex's/opencode's own turn-boundary mechanism actually surfaces this
 in-pane prompt to the agent before it exits the way Claude Code's Stop hook
 does — that's Phase 2 item 4 territory (native Face B per harness), not
 Phase 4.
+
+---
+
+## Real harness quota sources — verified locally, 2026-07-27
+
+Investigation, not a code change: B7 says `QuotaReported` has exactly one
+producer (the `TaskCompleted` handler in `cmd/orchestra/main.go`, deriving
+`consumed` from the harness's self-reported `usage.Numerator()`). The
+question was whether any harness exposes its *real* subscription quota so
+Orchestra can stop relying on operator-entered static caps plus estimated
+token consumption. Two of three do. Everything below was read off this
+machine's own installs, not recalled.
+
+### Claude Code — statusline stdin (confirmed)
+
+The JSON blob Claude Code pipes to `statusLine.command` on every render
+carries server-reported rate-limit levels. `~/.claude/statusline.sh` already
+reads them:
+
+- `.rate_limits.five_hour.used_percentage`
+- `.rate_limits.seven_day.used_percentage`
+
+plus `.context_window.{used_percentage,total_input_tokens,context_window_size}`,
+`.cost.total_cost_usd`, `.session_id`. These are percentages of the real
+subscription pool, not estimates, and the two windows map 1:1 onto
+`router.QuotaWindowLimits{FiveHour, Weekly}`. High frequency, zero cost.
+
+Note: `claude.ai/api/organizations/{org_id}/usage` also exists but is
+authenticated by **claude.ai session cookies, not an API key** — wiring it
+would make Orchestra hold and refresh a logged-in browser session. The
+statusline path avoids that entirely and should be preferred.
+
+### Codex — `rate_limits` in the session rollout (confirmed)
+
+Every `token_count` event in `~/.codex/sessions/YYYY/MM/DD/rollout-*.jsonl`
+carries a `rate_limits` object, e.g.:
+
+```json
+"rate_limits": {
+  "limit_id": "codex",
+  "primary":   { "used_percent": 20.0, "window_minutes": 10080, "resets_at": 1785650936 },
+  "secondary": null,
+  "credits":   { "has_credits": false, "unlimited": false, "balance": "0" },
+  "plan_type": "plus",
+  "rate_limit_reached_type": null
+}
+```
+
+Richer than Claude's: `window_minutes` makes the window self-describing
+(10080 = weekly) and `resets_at` is absolute. There is **no `codex usage`
+subcommand** — the transport is the rollout file, or `codex app-server`,
+which emits the same events live.
+
+### opencode — no first-class quota surface
+
+- `opencode stats` is historical accounting only (cost/tokens/tools across
+  past sessions). No limits, no remaining.
+- Zen is an OpenAI-compatible gateway at `https://opencode.ai/zen/v1` (and
+  `/zen/go/v1`). The binary contains `x-ratelimit-limit` /
+  `-remaining` / `-reset` / `-reset-after`, so the Zen free tier's **daily**
+  quota arrives as response headers, not via a queryable endpoint. Capturing
+  it requires intercepting a response — an opencode plugin
+  (`~/.config/opencode/plugin/`) is the only clean hook.
+
+### Design consequences (not yet implemented)
+
+1. **Percentages are a level, not a delta.**
+   `router.QuotaAvailability.sumSince` *sums* `consumed` across
+   `QuotaReported` events. Feeding a used-percentage into that sum is wrong
+   by construction. A real-quota feed needs a second `Availability`
+   implementation that reads the **latest** report per harness. `Availability`
+   is already an interface (`internal/router/router.go`), so this is a swap,
+   not a rewrite — and the additive `sumSince` path must stay for the
+   estimate-based producer (spec §5.2.1 receipts are genuinely additive
+   across rotations).
+2. **Static `quota_limit_5h`/`quota_limit_weekly` become unnecessary** for
+   Claude and Codex, since the harness reports its own fraction of pool and
+   the 80% conservative rule applies directly with no operator-entered cap.
+   Keep the static path as the fallback for opencode.
+3. **`QuotaWindowLimits{FiveHour, Weekly}` is too narrow.** Codex's windows
+   are self-describing via `window_minutes`, and opencode's Zen tier is
+   **daily** — a window Orchestra has no concept of today. A generic
+   `[]{WindowMinutes, UsedPercent, ResetsAt}` fits all three; the current
+   two named fields fit only Claude.
+4. **Push path**: statusline script (Claude) and a rollout-tail or
+   app-server reader (Codex) POST to a new endpoint alongside
+   `/v1/harness/turn` in `cmd/orchestra/main.go` — the existing hook-ingress
+   pattern — appending `QuotaReported`. That gives B7 a second, *live*
+   producer next to the post-hoc one, and covers the case CLAUDE.md already
+   flags: a harness that never completes a task cleanly (the stuck `wA` pane)
+   currently under-counts its consumption forever, because the only producer
+   fires on completion.

cmd/orchestra/main.go

@@ -302,8 +302,58 @@ func main() {
 				log.Printf("route task: %v", routeErr)
 			}
 		}
+		// B7 (AUDIT.md): QuotaReported has no other producer, so router's
+		// 5h/weekly availability filter and the brief's quota_consumed are
+		// permanently zero without this. Fed by the same per-harness usage
+		// read as the receipt above (spec §7.2 — "same per-harness session
+		// state as §5.2.1"); harness_id comes from the lease this completion
+		// closes out, before it's released.
+		if t.Lease != nil && t.Lease.HarnessID != "" {
+			qp, _ := json.Marshal(map[string]any{
+				"harness_id": t.Lease.HarnessID,
+				"consumed":   float64(usage.Numerator()),
+			})
+			qe := domain.Event{ID: id(), Type: "QuotaReported", TaskID: "system", Payload: qp, Surface: string(authz.System)}
+			if err := s.Append(qe); err != nil {
+				log.Printf("quota report: %v", err)
+			}
+		}
 		json.NewEncoder(w).Encode(e)
 	})
+	// /v1/harness/turn is the unified turn-decision endpoint (AUDIT.md Phase
+	// 2 items 1-2): the Face-B stop hook posts here on every ordinary turn
+	// boundary (report marker absent — /v1/harness/complete covers task
+	// completion separately) and gets back exactly one of continue /
+	// prepare_handoff / rotate_now / refuse, per spec §5.3. This replaces
+	// what would otherwise be separate ad-hoc marker-file conventions per
+	// decision.
+	mux.HandleFunc("/v1/harness/turn", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		if harnessToken != "" && r.Header.Get("Authorization") != "Bearer "+harnessToken {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+		if coordinator == nil {
+			http.Error(w, "coordinator not configured", http.StatusServiceUnavailable)
+			return
+		}
+		var p struct {
+			TaskID string `json:"task_id"`
+		}
+		if json.NewDecoder(r.Body).Decode(&p) != nil || p.TaskID == "" {
+			http.Error(w, "task_id is required", http.StatusBadRequest)
+			return
+		}
+		decision, err := coordinator.TurnDecision(r.Context(), p.TaskID)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]string{"decision": decision})
+	})
 	mux.HandleFunc("/v1/brief", func(w http.ResponseWriter, r *http.Request) {
 		to := time.Now().UTC()
 		from := to.Add(-12 * time.Hour)

deploy/hooks/orchestra-stop.sh

@@ -2,8 +2,9 @@
 # Claude Code Stop hook — fires on every turn boundary, not just completion.
 # Convention: the agent signals "this task is done" by writing a report file
 # named .orchestra-report.md at the worktree root before stopping. If that
-# marker is absent, this is an ordinary turn boundary and the hook is a
-# no-op — do not treat every stop as completion (AUDIT.md B3).
+# marker is present, report completion. If it is absent, this is an ordinary
+# turn boundary — ask the unified turn-decision endpoint (AUDIT.md B3, Phase
+# 2 items 1-2) what to do instead of no-op'ing.
 #
 # Requires: ORCHESTRA_TASK_ID and ORCHESTRA_URL set in the pane's env.
 # Optional: ORCHESTRA_HARNESS_TOKEN if the server requires one.
@@ -21,28 +22,49 @@ cwd="$(printf '%s' "$payload" | jq -r '.cwd // empty')"
 [ -z "${ORCHESTRA_TASK_ID:-}" ] && exit 0
 [ -z "${ORCHESTRA_URL:-}" ] && exit 0
 
-report_file="${cwd:-.}/.orchestra-report.md"
-[ -f "$report_file" ] || exit 0
-
-report="$(cat "$report_file")"
-
 auth_header=""
 if [ -n "${ORCHESTRA_HARNESS_TOKEN:-}" ]; then
 	auth_header="Authorization: Bearer ${ORCHESTRA_HARNESS_TOKEN}"
 fi
 
-body="$(jq -n \
-	--arg task_id "$ORCHESTRA_TASK_ID" \
-	--arg transcript_path "$transcript_path" \
-	--arg report "$report" \
-	'{task_id: $task_id, transcript_path: $transcript_path, report: $report}')"
+report_file="${cwd:-.}/.orchestra-report.md"
 
-if curl -fsS -X POST "${ORCHESTRA_URL%/}/v1/harness/complete" \
+if [ -f "$report_file" ]; then
+	report="$(cat "$report_file")"
+
+	body="$(jq -n \
+		--arg task_id "$ORCHESTRA_TASK_ID" \
+		--arg transcript_path "$transcript_path" \
+		--arg report "$report" \
+		'{task_id: $task_id, transcript_path: $transcript_path, report: $report}')"
+
+	if curl -fsS -X POST "${ORCHESTRA_URL%/}/v1/harness/complete" \
+		-H "Content-Type: application/json" \
+		${auth_header:+-H "$auth_header"} \
+		-d "$body" >/dev/null 2>&1; then
+		rm -f "$report_file"
+	else
+		echo "orchestra-stop: failed to report completion" >&2
+		exit 2
+	fi
+	exit 0
+fi
+
+body="$(jq -n --arg task_id "$ORCHESTRA_TASK_ID" '{task_id: $task_id}')"
+
+response="$(curl -fsS -X POST "${ORCHESTRA_URL%/}/v1/harness/turn" \
 	-H "Content-Type: application/json" \
 	${auth_header:+-H "$auth_header"} \
-	-d "$body" >/dev/null 2>&1; then
-	rm -f "$report_file"
-else
-	echo "orchestra-stop: failed to report completion" >&2
+	-d "$body" 2>/dev/null)" || {
+	echo "orchestra-stop: failed to reach turn-decision endpoint" >&2
+	exit 0
+}
+
+decision="$(printf '%s' "$response" | jq -r '.decision // empty')"
+
+if [ "$decision" = "refuse" ]; then
+	echo "orchestra-stop: turn decision is refuse — this turn boundary is not safe to stop at" >&2
 	exit 2
 fi
+
+exit 0

internal/orchestrator/orchestrator.go

@@ -175,6 +175,11 @@ type Coordinator struct {
 	loaded    bool
 	healthMu  sync.RWMutex
 	health    MonitorHealth
+	// Hard is the occupancy threshold Monitor's periodic rotate() runs
+	// against, mirrored here so TurnDecision (the synchronous, per-turn
+	// counterpart driven by the Face-B stop hook) evaluates the same
+	// threshold rather than needing its own copy passed in by the caller.
+	Hard float64
 }
 
 type MonitorHealth struct {
@@ -367,6 +372,7 @@ func (c *Coordinator) Monitor(ctx context.Context, hard float64, interval time.D
 		c.setMonitorHealth(err, 0)
 		return err
 	}
+	c.Hard = hard
 	if interval <= 0 {
 		interval = 30 * time.Second
 	}
@@ -595,6 +601,95 @@ func (c *Coordinator) rotate(ctx context.Context, hard float64) {
 	}
 }
 
+// Turn decision verdicts (spec §5.3, AUDIT.md Phase 2 items 1-2). These are
+// the only valid results of TurnDecision and the only values the
+// POST /v1/harness/turn endpoint may return.
+const (
+	TurnContinue       = "continue"
+	TurnPrepareHandoff = "prepare_handoff"
+	TurnRotateNow      = "rotate_now"
+	TurnRefuse         = "refuse"
+)
+
+// TurnDecision evaluates a single leased task's rotation state synchronously,
+// at a harness-reported turn boundary, and acts on the result. It mirrors
+// rotate()'s per-task logic (occupancy → turn-boundary → handoff-file →
+// release) but is invoked once per turn from the Face-B stop hook instead of
+// on Monitor's ticker, so an agent that's about to stop gets an authoritative
+// answer instead of waiting for the next tick. `refuse` covers every case
+// where continuing to let the harness stop would be unsafe: the turn
+// boundary can't be verified, or release/anchor certification failed.
+func (c *Coordinator) TurnDecision(ctx context.Context, taskID string) (string, error) {
+	c.loadSessions()
+	c.mu.Lock()
+	session, ok := c.sessions[taskID]
+	c.mu.Unlock()
+	if !ok {
+		return "", fmt.Errorf("orchestrator: no session for task %q", taskID)
+	}
+	task, ok := c.Store.Task(taskID)
+	if !ok || task.State != domain.StateLeased {
+		return "", fmt.Errorf("orchestrator: task %q not leased", taskID)
+	}
+	a, err := c.adapterFor(taskID, session)
+	if err != nil {
+		return "", fmt.Errorf("orchestrator: adapter: %w", err)
+	}
+	occupancy, err := a.Occupancy(session)
+	if err != nil {
+		return "", fmt.Errorf("orchestrator: occupancy: %w", err)
+	}
+	if occupancy < c.Hard {
+		return TurnContinue, nil
+	}
+	if boundary, ok := a.(herdr.TurnBoundary); ok {
+		atBoundary, boundaryErr := boundary.AtTurnBoundary(ctx, session)
+		if boundaryErr != nil {
+			c.recordTurnBoundaryDegraded()
+			return TurnRefuse, nil
+		}
+		if !atBoundary {
+			return TurnRefuse, nil
+		}
+	} else {
+		c.recordTurnBoundaryDegraded()
+	}
+	if requester, ok := a.(herdr.HandoffRequester); ok {
+		if _, statErr := os.Stat(filepath.Join(session.Worktree, herdr.HandoffFile)); statErr != nil {
+			if !session.HandoffRequested {
+				if reqErr := requester.RequestHandoff(ctx, session); reqErr == nil {
+					session.HandoffRequested = true
+					c.mu.Lock()
+					c.sessions[taskID] = session
+					_ = c.saveSessionsLocked()
+					c.mu.Unlock()
+				}
+			}
+			return TurnPrepareHandoff, nil
+		}
+	}
+	ref, err := a.Release(ctx, session)
+	if err != nil || ref == "" {
+		return TurnRefuse, nil
+	}
+	anchorSHA, err := herdr.HeadSHA(session.Worktree)
+	if err != nil {
+		// Cannot certify the anchor: refuse rather than release with an
+		// invalid TaskReleased payload, same as rotate()'s bare continue.
+		return TurnRefuse, nil
+	}
+	b, _ := json.Marshal(map[string]string{"handoff_ref": ref, "reason": "threshold", "anchor_sha": anchorSHA})
+	e := domain.Event{ID: domain.NewID(), Type: "TaskReleased", TaskID: taskID, Version: task.Version + 1, Payload: b, Surface: string(authz.System)}
+	if err := c.Store.Append(e); err != nil {
+		return TurnRefuse, nil
+	}
+	c.mu.Lock()
+	delete(c.sessions, taskID)
+	_ = c.saveSessionsLocked()
+	c.mu.Unlock()
+	return TurnRotateNow, nil
+}
+
 func (c *Coordinator) Start(ctx context.Context, e domain.Event) error {
 	if e.Type != "TaskLeased" {
 		return nil

internal/orchestrator/rotation_test.go

@@ -30,8 +30,8 @@ func (a *fakeAdapter) Release(context.Context, herdr.Session) (string, error) {
 	a.releases++
 	return a.ref, nil
 }
-func (a *fakeAdapter) Kill(context.Context, herdr.Session) error         { return nil }
-func (a *fakeAdapter) Occupancy(herdr.Session) (float64, error)         { return a.occupancy, nil }
+func (a *fakeAdapter) Kill(context.Context, herdr.Session) error { return nil }
+func (a *fakeAdapter) Occupancy(herdr.Session) (float64, error)  { return a.occupancy, nil }
 func (a *fakeAdapter) AtTurnBoundary(context.Context, herdr.Session) (bool, error) {
 	return a.boundary, nil
 }
@@ -137,6 +137,108 @@ func TestRotationEmitsValidReleaseWithAnchorSHA(t *testing.T) {
 
 func mustJSON(v any) []byte { b, _ := json.Marshal(v); return b }
 
+// TestTurnDecision guards AUDIT.md Phase 2 items 1-2: the synchronous,
+// per-turn counterpart to rotate() must return the same verdicts the
+// periodic ticker would compute, and rotate_now must actually perform the
+// release (not just report what rotate() would eventually do).
+func TestTurnDecision(t *testing.T) {
+	repo := t.TempDir()
+	run(t, repo, "init")
+	run(t, repo, "config", "user.email", "t@t")
+	run(t, repo, "config", "user.name", "t")
+	run(t, repo, "commit", "--allow-empty", "-m", "init")
+
+	newCoordinator := func(a *fakeAdapter) (*orchestrator.Coordinator, *store.Store, domain.Task) {
+		s, err := store.Open(t.TempDir())
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := s.Append(domain.Event{ID: domain.NewID(), Type: "TaskCreated", TaskID: "t1", Surface: string(authz.System), Payload: mustJSON(map[string]any{
+			"source": "jsonl", "external_id": "1", "project": "p",
+		})}); err != nil {
+			t.Fatal(err)
+		}
+		task := s.Tasks()[0]
+		c := &orchestrator.Coordinator{Store: s, Worktrees: worktrees{path: repo}, Adapters: adapters{a}, StatePath: t.TempDir() + "/sessions.json", Hard: .8}
+		leaseEvt, err := s.Lease(task.ID, "h1", time.Minute)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := c.Start(context.Background(), leaseEvt); err != nil {
+			t.Fatal(err)
+		}
+		return c, s, task
+	}
+
+	t.Run("continue below threshold", func(t *testing.T) {
+		a := &fakeAdapter{occupancy: .5}
+		c, _, task := newCoordinator(a)
+		decision, err := c.TurnDecision(context.Background(), task.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if decision != orchestrator.TurnContinue {
+			t.Fatalf("decision=%q want %q", decision, orchestrator.TurnContinue)
+		}
+	})
+
+	t.Run("refuse when not at turn boundary", func(t *testing.T) {
+		a := &fakeAdapter{occupancy: .95, boundary: false}
+		c, _, task := newCoordinator(a)
+		decision, err := c.TurnDecision(context.Background(), task.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if decision != orchestrator.TurnRefuse {
+			t.Fatalf("decision=%q want %q", decision, orchestrator.TurnRefuse)
+		}
+	})
+
+	t.Run("rotate_now releases and emits a valid TaskReleased", func(t *testing.T) {
+		a := &fakeAdapter{occupancy: .95, boundary: true}
+		c, st, task := newCoordinator(a)
+		artifactRef, err := st.PutArtifact([]byte("handoff"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		a.ref = artifactRef
+		decision, err := c.TurnDecision(context.Background(), task.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if decision != orchestrator.TurnRotateNow {
+			t.Fatalf("decision=%q want %q releases=%d", decision, orchestrator.TurnRotateNow, a.releases)
+		}
+		if a.releases == 0 {
+			t.Fatal("adapter Release was never invoked")
+		}
+		got, ok := st.Task(task.ID)
+		if !ok || got.State != domain.StateQueued {
+			t.Fatalf("task state=%v ok=%v, want queued", got.State, ok)
+		}
+	})
+
+	t.Run("prepare_handoff requests handoff without releasing", func(t *testing.T) {
+		a := &handoffRequestingAdapter{fakeAdapter: fakeAdapter{occupancy: .95, boundary: true}}
+		c, st, task := newCoordinator(&a.fakeAdapter)
+		c.Adapters = adapters{a}
+		decision, err := c.TurnDecision(context.Background(), task.ID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if decision != orchestrator.TurnPrepareHandoff {
+			t.Fatalf("decision=%q want %q", decision, orchestrator.TurnPrepareHandoff)
+		}
+		if a.releases != 0 {
+			t.Fatal("adapter Release was invoked, expected only a handoff request")
+		}
+		got, ok := st.Task(task.ID)
+		if !ok || got.State != domain.StateLeased {
+			t.Fatalf("task state=%v ok=%v, want leased", got.State, ok)
+		}
+	})
+}
+
 // TestStartBlocksOnInvalidPickup guards AUDIT.md's B6/Phase 4 item 4:
 // Coordinator.Start must run §6.2 pickup validation against the real
 // worktree before bootstrapping a successor onto a handoff_ref, and refuse
@@ -294,8 +396,8 @@ func (a *noBoundaryAdapter) Release(context.Context, herdr.Session) (string, err
 	a.releases++
 	return a.ref, nil
 }
-func (a *noBoundaryAdapter) Kill(context.Context, herdr.Session) error         { return nil }
-func (a *noBoundaryAdapter) Occupancy(herdr.Session) (float64, error)         { return a.occupancy, nil }
+func (a *noBoundaryAdapter) Kill(context.Context, herdr.Session) error { return nil }
+func (a *noBoundaryAdapter) Occupancy(herdr.Session) (float64, error)  { return a.occupancy, nil }
 
 func setupRotationTask(t *testing.T, repo string) (*store.Store, string, domain.Task, string) {
 	t.Helper()