Garry Tan b86ef06706 test(security): live + fixture-replay bench harness with 500-case capture ...

Adds two new benches that permanently guard the v2 tuning:

- security-bench-ensemble-live.test.ts (opt-in via GSTACK_BENCH_ENSEMBLE=1).
  Runs full ensemble on BrowseSafe-Bench smoke with real Haiku calls.
  Worker-pool concurrency (default 8, tunable via
  GSTACK_BENCH_ENSEMBLE_CONCURRENCY) cuts wall clock from ~2hr to
  ~25min on 500 cases. Captures Haiku responses to fixture for replay.
  Subsampling via GSTACK_BENCH_ENSEMBLE_CASES for faster iteration.
  Stop-loss iterations write to ~/.gstack-dev/evals/stop-loss-iter-N-*
  WITHOUT overwriting canonical fixture.

- security-bench-ensemble.test.ts (CI gate, deterministic replay).
  Replays captured fixture through combineVerdict, asserts
  detection >= 55% AND FP <= 25%. Fail-closed when fixture is missing
  AND security-layer files changed in branch diff. Uses
  `git diff --name-only base` (two-dot) to catch both committed
  and working-tree changes — `git diff base...HEAD` would silently
  skip in CI after fixture lands.

- browse/test/fixtures/security-bench-haiku-responses.json — 500 cases
  × 3 classifier signals each. Header includes schema_version, pinned
  model, component hashes (prompt, exemplars, thresholds, combiner,
  dataset version). Any change invalidates the fixture and forces
  fresh live capture.

- docs/evals/security-bench-ensemble-v2.json — durable PR artifact
  with measured TP/FN/FP/TN, 95% CIs, knob state, v1 baseline delta.
  Checked in so reviewers can see the numbers that justified the ship.

Measured baseline on the new harness:
  TP=146 FN=114 FP=55 TN=185 → 56.2% / 22.9% → GATE PASS

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

2026-04-21 20:32:15 -07:00

..

security-bench-ensemble-v2.json

test(security): live + fixture-replay bench harness with 500-case capture

2026-04-21 20:32:15 -07:00