Fixes#2159. The Stop hook emits feedback via
`hookSpecificOutput: {hookEventName: "Stop", additionalContext}`, but
`Stop`/`SubagentStop` are NOT members of CC's `hookSpecificOutput`
discriminated union (coreSchemas.ts — valid members are PreToolUse,
PostToolUse, UserPromptSubmit, SessionStart, etc.). So the emitted shape
violates CC's documented hook-output schema.
Impact is CC-version-dependent — important nuance, established empirically:
- Reporter (array0224-cloud) on CLI 2.1.150 / 2.1.152: CC rejects the
Stop feedback; the block/reason never reaches the model, so the
auto-rewake/fix loop is lost. (Detection still runs + logs.)
- On CLI 2.1.160 (current) the asyncRewake completion path is lenient:
its gate is `isSyncHookJSONOutput` (hooks.ts) which is just
`!(json.async === true)` — NOT a strict schema parse. So the invalid
hookSpecificOutput is tolerated: metrics + rewakeSummary are still
consumed and the model still receives the findings. I could NOT
reproduce the rejection on 2.1.160, and BQ confirms Stop-path
vulns_found metrics are recorded normally (~21k with-vuln fires / 3d),
i.e. NOT dropped. (An earlier draft of this message claimed metrics
were dropped — that was wrong; corrected after checking telemetry +
repro'ing the old plugin on 2.1.160.)
So this is defensive schema-correctness: the plugin should emit output
that conforms to CC's documented union regardless of how strictly a given
CC version validates it. The reporter's environment validates strictly;
relying on the current version's leniency is fragile.
Fix (CC's documented asyncRewake "clean pattern" — hooks.ts: "error text
on stderr, JSON on stdout"):
- For Stop/SubagentStop, emit_metrics writes guidance to stderr (the
asyncRewake body channel CC delivers via `stderr || stdout`) and sets
top-level `decision: "block"` + `reason` (valid SyncHookJSONOutput
fields; also the documented sync Stop-hook contract for the `-p`
fallback). It does NOT emit a Stop hookSpecificOutput.
- PostToolUse (commit-review, push-sweep) is unchanged — valid union
member, keeps the modern hookSpecificOutput protocol.
Verified locally on macOS Python 3.13:
- py_compile clean.
- 11 new tests (test_2159_stop_hook_schema.py) pin the contract: Stop
output carries no hookSpecificOutput, uses top-level decision/reason,
writes guidance to stderr; the emitted hookEventName (when present) is
a valid union member. 2 existing tests that asserted the buggy
Stop->hookSpecificOutput shape were corrected. Full suite 464/464
pass + 2 skipped.
- END-TO-END in /tmux on CLI 2.1.160:
* FIXED plugin (2.0.3): staged pickle.loads + os.system, benign edit
pulls the file into review_set; Stop LLM review found 2 critical
vulns; CC delivered a clean rewake ("Background security review
found issues" + both findings). All hooks (UPS, PostToolUse[Edit]
pattern, PostToolUse[Bash] commit-review, Stop) fired clean; zero
schema rejections / errors / http_err in the debug log.
* OLD plugin (2.0.2) on the SAME 2.1.160: also delivered Stop feedback
(confirming the no-repro-on-latest finding above) — which proves the
fix carries NO regression risk on current CC while making the output
robust for the stricter versions where it actually breaks.
Version bumped 2.0.2 -> 2.0.3 per the per-PR-bump policy (#2114: a bump is
the only way the fix reaches the existing fleet — relevant for users still
on the CC versions where this breaks).
Closes#2159.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
sagemaker-ai was dropped from the marketplace in #1762 (validate-plugins
adoption) due to a manifest/YAML error. AWS has since fixed it; the plugin
validates clean at awslabs/agent-plugins@187edde (claude plugin validate passes).
Re-listed as a git-subdir source SHA-pinned to current monorepo HEAD,
matching its sibling AWS entries (deploy-on-aws, databases-on-aws).
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
