A claim made with --session <name> stored the name, but the PreToolUse gate compares the hook payload's session_id, so the gate refused every edit of the claiming session and a later release without the flag exited 3. caller() now takes CLAUDE_CODE_SESSION_ID whenever it is set and falls back to --session only for other runtimes. test_council covers a claim and release with --session under a Claude Code session (negative control against the old caller fails). Claims made with --session before this fix go stale after an hour without a heartbeat and can then be taken over.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
