## Verification Report

**Change**: rook-680-production-observability-and-metrics
**Verdict**: PASS

---

### Completeness
- Tasks reviewed: 12
- Tasks complete: 12
- Tasks incomplete: 0

All checklist items in `tasks.md` are marked complete.

---

### Commands Executed
Workdir: `clients/rook`

- `cargo fmt --all -- --check` ✅ passed
- `cargo clippy --all-targets -- -D warnings` ✅ passed
- `cargo test` ✅ passed

Observed test execution summary from `cargo test`:
- unit/integration/doc tests passed with no failures
- relevant metrics verification tests executed from `clients/rook/src/server/mod.rs`

---

### Artifact and Code Verification

#### Request metrics across `/api/*` and `/v1/*`
Verified in:
- `clients/rook/src/transport/middleware.rs`
- `clients/rook/src/server/mod.rs`

Evidence:
- `metrics_route_counts_requests_with_stable_endpoint_labels` asserts scraped metrics for:
  - `admin_api` `/api/health` with `2xx`
  - `admin_api` `/api/accounts/{account_id}` with `4xx`
  - `gateway_v1` `/v1/models` with `2xx`
  - `gateway_v1` `/v1/chat/completions` with `5xx`
- Same test asserts latency histogram count series for both `/api/*` and `/v1/*` routes.
- Request body content such as `"super secret prompt"` is exercised in the request path while metrics assertions remain bounded to surface/endpoint/status class labels only.

#### Upstream failure metrics
Verified in:
- `clients/rook/src/gateway/handlers.rs`
- `clients/rook/src/server/mod.rs`

Evidence:
- `metrics_route_counts_upstream_success_http_error_and_route_rejected_outcomes` proves:
  - success does not increment failure metrics
  - `http_error` increments with routed labels
  - `account_misconfigured` increments
  - `network_error` increments
  - `route_rejected` increments with `unrouted` fallback labels
  - secret-like account input is normalized to `unlabeled`

#### Rate-limit outcomes
Verified in:
- `clients/rook/src/transport/rate_limit.rs`
- `clients/rook/src/server/mod.rs`

Evidence:
- `metrics_route_counts_rate_limit_rejections` proves allow/reject emission for:
  - `admin_api` `/api/accounts`
  - `gateway_v1` `/v1/models`
- Test also confirms `GET /api/metrics` remains reachable for scraping.

#### Idempotency outcomes
Verified in:
- `clients/rook/src/idempotency/middleware.rs`
- `clients/rook/src/server/mod.rs`

Evidence:
- `metrics_route_counts_idempotency_pass_replay_and_conflict_outcomes` proves bounded `pass`, `replay`, `in_progress`, and `key_mismatch` outcomes.
- `chat_idempotency_fails_closed_when_storage_is_unavailable` proves bounded `unavailable` outcome.
- Existing assertions verify secret-bearing request data is not emitted into metric labels.

#### Scrape endpoint contract
Verified in:
- `clients/rook/src/admin/mod.rs`
- `clients/rook/src/admin/handlers.rs`
- `clients/rook/src/server/mod.rs`

Evidence:
- `/api/metrics` remains the single scrape endpoint.
- `metrics_route_exposes_prometheus_scrape_output` asserts content type:
  - `application/openmetrics-text; version=1.0.0; charset=utf-8`
- Same test asserts presence of all required metric families:
  - `rook_http_requests`
  - `rook_http_request_duration_seconds`
  - `rook_rate_limit_outcomes`
  - `rook_idempotency_outcomes`
  - `rook_upstream_failures`

#### Label safety and boundedness
Verified in:
- `clients/rook/src/observability.rs`

Evidence:
- `looks_secret_like` rejects secret-like values.
- `normalization_helpers_keep_labels_bounded_and_secret_safe` now asserts:
  - `normalize_account_label(Some("Bearer sk-secret")) == "unlabeled"`
  - `normalize_account_label(Some("sk-secret-value")) == "unlabeled"`
  - secret-like model labels also fall back safely
  - unmatched/unbounded labels normalize to bounded fallback values

---

### Design Coherence
The implementation matches the design decisions:
- uses the existing `Observability` registry as the single metrics subsystem
- keeps request instrumentation in shared transport middleware
- keeps rate-limit outcomes in transport middleware
- keeps idempotency outcomes route-local
- emits upstream failure metrics from gateway handlers
- preserves `/api/metrics` as the single admin-surface scrape endpoint
- does not expand scope into tracing, dashboards, collectors, alert rules, or analytics storage

---

### Verdict
PASS

The change now satisfies the authoritative proposal/spec/design/tasks with passing scoped verification commands and direct test evidence for request metrics, upstream failure metrics, rate-limit outcomes, idempotency outcomes, scrape endpoint behavior, and label-safety boundaries.
