Instrument metrics and rollout decisions

Instrument Personal Knowledge Assistant API with flags, probes, secrets, on-call owner so solo builder operating pka.example for 50 beta users can answer: demand, errors, latency/age, saturation. Emit fields needed by readyz_ok, kill_switch_seconds, secret_age_days ≤ 30 with bounded labels. Sample successful high-volume traces; keep errors and rollout transitions denser within policy.

Define at least one alert that would fire for CAP-OPS-PKA-12, with a for/pending window that survives deploy blips. Missing scrape or missing revision labels must not look like health. Include a trace/log example id format you will actually search.

Add a unit/integration check that metrics increment on the happy path and on the app runs on laptop only — no probes, no owner, secret in .env committed branch. Store machine-readable output in CI artifacts when practical.

Cardinality discipline: tenant and revision are usually enough; raw question text is not a label. Exemplars or trace links beat screenshots alone when debugging CAP-OPS-PKA-12. Define who owns alert fatigue review. If you export to a vendor, record retention and access. Synthetic probes should use non-sensitive fixtures and still exercise https://pka.example/v1/ask. Practice the query you will type at 2am once, while calm.

Document the exact PromQL or log query in the runbook stub for this service. Verify histograms have buckets around your SLO target. Add a canary synthetic check that exercises the oracle path every few minutes in staging. Confirm that PII redaction happens before export. Track build/version as a label on the golden signals. Delete noisy debug logs before they become accidental product dependencies. In this chapter the product is Personal Knowledge Assistant API with flags, probes, secrets, on-call owner, the human stakeholder is solo builder operating pka.example for 50 beta users, and the incident id you design against is CAP-OPS-PKA-12. Re-state the oracle in your notes — ship v1.2.0: smoke+readyz pass; kill switch drill < 60s; on-call roster non-empty — and keep the invariant visible: versioned release with readyz, flag kill switch, rotated secret, named on-call. Track readyz_ok, kill_switch_seconds, secret_age_days ≤ 30 as the scoreboard. Surface under change control: https://pka.example/v1/ask. If you only have forty minutes, finish the fixture for app runs on laptop only — no probes, no owner, secret in .env committed before polishing UI. Promotion language stays ternary: promote, hold, or roll back based on evidence, not hope.