Mohamed Hegazy 475038edfc
security-guidance: emit HTTP error codes + fix sdk_bootstrap phase/err encoding
Fills two failure-visibility gaps in plugin telemetry.

## Gap 1: HTTP errors from _call_claude invisible

Before: a 4xx/5xx response from the LLM API caused `_call_claude` to
return None and produce ZERO fingerprint in tengu_hook_plugin_metrics.
A failed call looked identical to "no review needed". The recent
deprecation-400 outage (PR #2105, output_format → output_config.format,
#2098) was invisible in aggregate dashboards until a user manually
reported errors from their debug log. Cohort-specific or partial
outages would never show up in BQ.

Fix: add `http_err_last` (most recent status) and `http_err_count`
to the existing `_USAGE` accumulator in `_base.py`. `_usage_metrics()`
snapshots them whenever count > 0 (skip-path no-pollute contract
preserved when count == 0). All `_call_claude` error sites now call
the new `_record_http_error()` helper alongside the existing
`_last_call_claude_http_error` module-state assignment.

Now any future API failure category is queryable in BQ in real time:

  SELECT
    DATE(server_timestamp, "America/Los_Angeles") AS d,
    CAST(JSON_VALUE(additional_metadata, "$.http_err_last") AS INT64) AS code,
    COUNT(*) AS n
  FROM ... WHERE event_name = "tengu_hook_plugin_metrics"
    AND JSON_VALUE(additional_metadata, "$.pluginId") LIKE "%security-guidance%"
    AND JSON_VALUE(additional_metadata, "$.http_err_count") IS NOT NULL
  GROUP BY d, code ORDER BY d, n DESC

## Gap 2: sdk_bootstrap_phase / sdk_bootstrap_err always NULL in BQ

Before: ensure_agent_sdk.py emitted these as strings (e.g. "pip",
"dns_fail"). CC's plugin-metrics pipeline silently drops
plugin-emitted string values — only bool|finite-number plugin metrics
reach BigQuery. (CC-core fields like `subscription_type` are exempt
because they're injected downstream of plugin validation.)

Confirmed empirically: ~185K BUILD_FAILED rows in BQ over the past 2
days had `sdk_bootstrap_phase` = NULL and `sdk_bootstrap_err` = NULL
despite the Python code emitting them. ~28K BUILD_FAILED sessions/day
had no diagnostic split — flying blind on whether the failures are
pip-no-match vs dns-fail vs ssl-verify vs proxy-auth etc.

Fix: encode phase + err_kind as stable integers via
SDK_BOOTSTRAP_PHASE_CODES and SDK_BOOTSTRAP_ERR_CODES. Phase: 1=pre,
2=venv, 3=pip, 4=main. Err: 10 known categories (1-10), 11-98
reserved, 99 = uncategorized catch-all (covers "exc:<X>", "other:<X>",
and unmapped strings). APPEND-ONLY for telemetry stability.

Also corrects the misleading "CC accepts string metric values"
comment in ensure_agent_sdk.py that led to the bug originally.

Verified locally on macOS Python 3.13:

  - py_compile clean.
  - 32 new tests in test_telemetry_failure_signals.py (added to
    internal test suite at sg-staging/tests/, not in this PR):

      * 4 HTTP-error tracking unit tests: _record_http_error increments
        count + tracks most-recent; handles None/invalid; -1 for
        network/timeout.
      * 4 _usage_metrics emission tests: empty when no activity;
        successful call has no http_err fields; failure-only has http_err
        and no api_calls; mixed has both.
      * 1 contract test: every emitted value is bool|finite-number
        (catches future regression of the string-dropping bug class).
      * 13 sdk_bootstrap encoding tests (parametrized over the 10 known
        err_kind categories + 5 catch-all shapes): each maps to the
        right integer; unknown phase = 0; unknown err = 99.
      * 1 static-shape regression catcher: every `err_kind = "..."`
        string in ensure_agent_sdk.main() must be in
        SDK_BOOTSTRAP_ERR_CODES (otherwise new err_kinds silently
        collapse to 99).
      * 2 emit-shape regression catchers: the assignments in main() go
        through _encode_phase / _encode_err_kind helpers (no raw
        strings); no literal string values for sdk_bootstrap_phase/err.
      * 1 comment-accuracy: the misleading "CC accepts string metric
        values" comment is gone.

  - Full suite: 437/437 pass + 2 skipped (live API tests, opt-in).

NOT verified end-to-end against BQ — would require shipping +
observing in production for 24h to confirm the http_err and
sdk_bootstrap_phase/err fields actually appear in
tengu_hook_plugin_metrics rows. The unit tests pin the contract; if
the wire shape is broken, BQ will show NULL for the new fields and we
revisit (with the same diagnostic the BUILD_FAILED bug gave us).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-31 08:34:35 -07:00
..
2026-05-26 14:06:52 -07:00