debugging-prod

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name: debugging-prod description: Investigate production issues for the self-hosted Vacation Price Tracker stack (project vpt-prod). Use when something is broken or suspicious in prod — 5xx/empty responses, a tracked trip with wrong/stale prices, a stuck or failing price-check workflow, missing notifications, slow/odd LLM chat behaviour, or a deploy that won't come healthy. Covers the read paths: docker logs on the prod host, structured app logs in Axiom (via pnpm prod:axiom), the /v1/admin/sql endpoint (via pnpm prod:query), the Temporal Web UI, Langfuse, and the /ready probe. From a Claude Code web session, pnpm prod:query and pnpm prod:axiom work out of the box using injected shell-env credentials (no .env.prod).

Debugging production (vpt-prod)

Production is the self-hosted Docker stack defined in infra/docker-compose.prod.yml (Compose project vpt-prod), pulling images from GHCR. This skill is the read/diagnose counterpart to the local debug-web skill — use it against the live host.

• debug-web → render/inspect the local UI with Playwright at https://localhost:3000 (you have the dev stack and a browser).
• debugging-prod (this skill) → diagnose the live system from its logs, database, workflow history, and LLM traces. You do not drive a prod browser here; you read prod's signals.

App logging is stdlib logging → stdout → Docker's json-file driver, and shipped to Axiom when AXIOM_TOKEN/AXIOM_DATASET are set in .env.prod (one dataset, vacation-price-tracker-prod, for api + worker + web — distinguished by service / component). LLM/MCP calls are traced in Langfuse.

Credentials & access (read this first in a web session)

A Claude Code web/remote session is NOT the prod host — there is no .env.prod, and the dev .env is useless for prod (BACKEND_URL there points at localhost). Instead the prod read-credentials are injected into the shell environment:

Env var	What it is	Used by
ADMIN_QUERY_URL	prod API origin (https://vacation-price-tracker.ethanasm.me)	pnpm prod:query (auto-resolved)
ADMIN_QUERY_TOKEN	bearer token for /v1/admin/sql	pnpm prod:query
AXIOM_QUERY_TOKEN	PAT with Query capability (the ingest token can't read)	pnpm prod:axiom
AXIOM_ORG_ID	Axiom org slug (showbook-egap)	pnpm prod:axiom

So the two read paths just work from a web session: pnpm prod:query "…" for Postgres and pnpm prod:axiom "…" for logs. The Docker / Temporal / Langfuse paths below require being on (or tunnelled to) the prod host and are not reachable from a plain web session. Check env | grep -E 'ADMIN_QUERY|AXIOM' if unsure what's available.

Querying Axiom — pnpm prod:axiom

Prefer the helper; it wraps the PAT auth, JSON escaping, and the column-oriented "tabular" response (fiddly to read by hand). Don't reach for the Axiom MCP tools first — that server's own token is usually expired in web sessions; the PAT helper is the reliable path. Raw curl (below) is the fallback.

pnpm prod:axiom "['vacation-price-tracker-prod'] | where _time > ago(24h) | summarize count() by service, level"
pnpm prod:axiom --json "['vacation-price-tracker-prod'] | where level == 'error' | take 20"

APL gotchas (each one cost a wasted query the first time):

• Always constrain time — | where _time > ago(24h). The _apl endpoint otherwise scans a ~1-year default window.
• The message column is msg, not message.
• App-supplied fields (logger, trip_id, workflow_id, count, …) fold into the fields map — query as ['fields']['logger'], not as top-level columns. Only CORE_FIELDS (_time, service, level, event, env, hostname, pid, msg, status) and the err.* allowlist are real columns. getschema / getDatasetFields won't list keys inside the map — sample a row.
• Third-party library logs (langfuse, temporalio, uvicorn) arrive with event == null — that's expected, not a wiring bug. App events carry a dotted event (e.g. trips.users.ok, admin.sql.executed).
• Low/zero volume usually means idle prod, not broken shipping — cross-check with pnpm prod:query "SELECT count(*) FROM trips" before assuming Axiom is down.

Raw fallback (if the helper is unavailable):

curl -sS -X POST "https://api.axiom.co/v1/datasets/_apl?format=tabular" \
  -H "Authorization: Bearer $AXIOM_QUERY_TOKEN" -H "X-AXIOM-ORG-ID: ${AXIOM_ORG_ID:-showbook-egap}" \
  -H "Content-Type: application/json" \
  -d '{"apl":"[\"vacation-price-tracker-prod\"] | where _time > ago(1h) and level in (\"warn\",\"error\") | sort by _time desc"}'

When Axiom retention has rolled off (or it's unconfigured), docker logs is the fallback — the stdout copy is JSON in prod.

The five read paths

1. docker logs on the prod host

First stop for crashes, stack traces, and startup failures. On the prod host (repo root, where .env.prod lives):

pnpm prod:ps                                  # what's up / restarting / unhealthy
pnpm prod:logs                                # all services, follow, last 100
# or target one service (compose service names: db redis temporal api worker web):
docker compose --env-file .env.prod -f infra/docker-compose.prod.yml logs --tail=200 api
docker compose --env-file .env.prod -f infra/docker-compose.prod.yml logs --tail=200 worker

The API logs RFC 7807 problem details and a one-line admin.sql … audit record per query (length + timing only, never the SQL). Logs rotate at 10 MB × 5 files.

2. /v1/admin/sql via pnpm prod:query

The DB is owned by FastAPI and is not exposed on the LAN. Inspect prod data through the bearer-authenticated, read-only SQL endpoint:

pnpm prod:query "SELECT count(*) FROM trips"
pnpm prod:query --json "SELECT id, status FROM trips WHERE status='Error'"
echo "SELECT now()" | pnpm prod:query

Reads ADMIN_QUERY_TOKEN + the API base URL. On the prod host that's PROD_API_URL/BACKEND_URL from .env.prod; in a web session it falls back to ADMIN_QUERY_URL from the shell env automatically (no .env.prod needed). Read-only is enforced server-side (Postgres READ ONLY txn, always rolled back), plus a 3 s statement timeout, 1000-row cap, and per-IP rate limit. Only SELECT/WITH/EXPLAIN/SHOW/TABLE/VALUES are accepted. See the recipe library below.

3. Temporal Web UI — workflow/activity failures

Price tracking runs in Temporal (PriceCheckWorkflow, RefreshAllTripsWorkflow, RunOptimizerWorkflow). When a refresh "does nothing", a trip is stuck, or the worker throws, the UI has the full history (inputs, retries, and the failure stack on the failed activity). In prod the Temporal frontend is on loopback 127.0.0.1:7235; the Web UI is not published by the prod compose, so tunnel to the host (e.g. ssh -L 8080:127.0.0.1:8080) or run the UI image against the frontend. Look for:

• Workflows in Failed/Terminated, or Running far longer than a normal run.
• The failed activity (usually filter_results_activity or a Skiplagged fetch) — its stack trace + whether Temporal is still retrying.
• Skiplagged 429s: the worker backs off and writes a partial snapshot rather than failing — expect retries, not a hard failure.

4. Langfuse — LLM/MCP traces

For chat misbehaving, bad tool calls, or MCP routing issues, open the Langfuse project (LANGFUSE_HOST, default https://us.cloud.langfuse.com). Traces appear only when LANGFUSE_PUBLIC_KEY/SECRET_KEY are set; otherwise tracing is a no-op and you fall back to docker logs api. Look at the trace for the request: the Groq prompt/response, which MCP tools were called, and their arguments/results.

5. /ready probe

GET /ready on the API checks database, Redis, and Temporal and returns 503 if any dependency is down (this backs the api container healthcheck). Quick triage:

curl -fsS http://127.0.0.1:8001/ready | jq    # on the prod host (loopback bind)
curl -fsS https://api.your-domain.com/ready | jq   # through the tunnel

{"database":"ok","redis":"ok","temporal":"ok"} → infra is healthy, look higher up. Any "error" → that dependency is the problem; check its container logs.

DB recipe library

The API owns these tables: users, trips, trip_flight_prefs, trip_hotel_prefs, price_snapshots, notification_rules, conversations, messages. Idempotency keys and the admin-SQL rate limiter live in Redis, not Postgres — there is no idempotency/outbox table to query; notification delivery is an at-least-once handoff processed by a worker activity.

-- Trips currently in an error state (worker marked them non-retriable)
SELECT id, user_id, trip_name, status, updated_at
FROM trips WHERE status = 'Error' ORDER BY updated_at DESC;

-- Is tracking actually running? Newest snapshot per trip (stale = worker stuck)
SELECT trip_id, max(created_at) AS last_snapshot
FROM price_snapshots GROUP BY trip_id ORDER BY last_snapshot ASC LIMIT 20;

-- Inspect a suspicious price: raw_data JSONB is kept for debugging
SELECT id, trip_id, flight_total, hotel_total, trip_total, created_at
FROM price_snapshots WHERE trip_id = '<TRIP_ID>' ORDER BY created_at DESC LIMIT 10;

-- Notification thresholds for a trip (why did/didn't an alert fire?)
SELECT * FROM notification_rules WHERE trip_id = '<TRIP_ID>';

-- A user's trips and prefs (airline / room-type filters drive worker filtering)
SELECT t.id, t.trip_name, t.status, f.airlines, h.preferred_room_types
FROM trips t
LEFT JOIN trip_flight_prefs f ON f.trip_id = t.id
LEFT JOIN trip_hotel_prefs  h ON h.trip_id = t.id
WHERE t.user_id = '<USER_ID>';

-- Per-user trip count vs the MAX_TRIPS_PER_USER cap (create_trip rejections)
SELECT user_id, count(*) FROM trips GROUP BY user_id ORDER BY count DESC;

-- Has migrations applied? (alembic stamps this table)
SELECT version_num FROM alembic_version;

Symptom → action decision tree

Symptom	Start here	Then
API 5xx / won't start / unhealthy	docker logs api; /ready	If a dep is error, check that container (db/redis/temporal)
/ready returns 503	the error field tells you which dep	logs for db/redis/temporal
Trip price wrong / stale	prod:query newest-snapshot recipe	if stale → Temporal UI for the workflow; inspect raw_data
Refresh "did nothing" / stuck	Temporal UI (workflow history)	worker logs; expect 429 backoff + partial snapshots, not failure
Trip stuck in Error	prod:query error-trips recipe	Temporal UI for the failed activity's stack
No notification fired	notification_rules recipe (thresholds)	worker logs for the notify activity
Chat / tool calls misbehaving	Langfuse trace	fall back to docker logs api if tracing disabled
Wrong airline/room filtering	trip_*_prefs recipe	apps/worker/CLAUDE.md (post-fetch filtering)
Deploy won't come healthy	prod:ps; docker logs of the new image	confirm IMAGE_TAG pulled; rerun pnpm prod:db:migrate
Auth / OAuth callback failing	docker logs api; check CORS_ALLOWED_ORIGINS	Cloudflare Tunnel + Google callback URL

Safety

Everything here is read-only. prod:query cannot mutate data (the endpoint forces a rolled-back READ ONLY transaction). Never paste secrets or full SQL with user identifiers into chat — the audit log deliberately records query length, not content. Schema changes go through Alembic (pnpm prod:db:migrate), never hand-run DDL.