Observability triage

Query Cloudflare Workers Observability for prod errors, count them correctly, and skip the noise that has already been investigated to a dead end. Apply the known-noise list below without re-investigating those entries.

Access

• Resolve the account at runtime, never hardcode it: the cloudflare-api MCP server pre-binds accountId in mcp__cloudflare-api__execute, and npx wrangler whoami prints it. The workers to triage are the ones this repo deploys (see deploy/alchemy/alchemy.run.ts): the main app worker plus the aux workers (audit engine, landing, self-host).
• Query via the cloudflare-api MCP server (mcp__cloudflare-api__execute). If its tools are absent, run its authenticate flow and give the user the URL, wrangler's OAuth token gets a 403 on the observability API (missing scope), so don't burn time on curl-with-wrangler-token.
• PostHog is the second error source but cannot see exceededMemory / canceled / responseStreamDisconnected outcomes, worker-outcome questions are answerable only here.

Query recipes (verified shapes)

POST /accounts/{account_id}/workers/observability/telemetry/query. All of these are load-bearing; the API's 400s are opaque:

• queryId: "adhoc" is required. Timeframe is epoch milliseconds: timeframe: { from, to }.

• Count invocations by outcome:

  {
    "queryId": "adhoc",
    "timeframe": { "from": 0, "to": 0 },
    "parameters": {
      "datasets": ["cloudflare-workers"],
      "filters": [
        { "key": "$metadata.type", "operation": "eq", "value": "cf-worker-event", "type": "string" }
      ],
      "calculations": [{ "operator": "count", "alias": "count" }],
      "groupBys": [
        { "value": "$workers.scriptName", "type": "string" },
        { "value": "$workers.outcome", "type": "string" }
      ],
      "limit": 100
    },
    "view": "calculations",
    "limit": 100
  }