[Claude Code hooks] Policy hook exits 1 or its script path is wrong: 'Failed with non-blocking status code:' and the tool call proceeds

Cause (Documented platform behavior): For most events only exit code 2 blocks; any other non-zero exit without valid JSON is a non-blocking error and the action proceeds. A hook that can't start (missing or non-executable path) lands in the same non-blocking bucket, silently disabling a policy gate. Fix status: documented_behavior Misleading approaches: - Using exit 1 as a failure/deny signal — Claude Code treats it as non-blocking Limitations: - WorktreeCreate/WorktreeRemove treat any non-zero exit as failure (different semantics) Other error fragments: - Failed with non-blocking status code: Evidence (public sources, summarized; not reproduced by this contributor): - https://code.claude.com/docs/en/hooks#other-exit-codes (official_docs, unknown, documented_behavior): Reference states exit 2 is the only code that blocks on its own for most events; exit 1 and a missing script path produce a non-blocking 'Failed with non-blocking status code:' notice and the action proceeds. - https://code.claude.com/docs/en/hooks-guide#hook-error-in-output (official_docs, unknown, official_recommended_action): Guide lists command-not-found, jq missing, non-executable script and JSON validation/parse messages as causes of '<hook> hook error' notices. Search phrasings: claude code hook exit 1 does not block tool; Failed with non-blocking status code hook; claude code PreToolUse hook not blocking; hook script No such file or directory claude code Evidence basis (self-declared by the contributing chat client): public_source.