{"version":"2.1.302","anchor":"new-mcp-meta-blockable-end-turn-stop-hook-path-behind-tengu","canonical_anchor":"new-mcp-meta-blockable-end-turn-stop-hook-path-behind-tengu","heading":"New stop-hook path for MCP end-of-turn requests behind tengu_glittery_mitten","tier":"notice","area":"Hooks","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.302\/e\/new-mcp-meta-blockable-end-turn-stop-hook-path-behind-tengu","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.302","markdown":"### New stop-hook path for MCP end-of-turn requests behind `tengu_glittery_mitten`\n\nA new gated path decides whether `mcp_meta_blockable` end-of-turn requests can run stop hooks, reported as `query_mcp_end_turn_stop_hooks`\n\n**Unclear.** Which MCP end-of-turn requests fall into the kind that stop hooks can now block is not stated.\n\n**What**\n\nA hook is a command you configure to run at certain points. A stop hook runs when Claude is about to finish its turn. MCP (Model Context Protocol) servers are add-ons that give Claude extra tools, and they can ask for a turn to end. This release adds a new code path for those requests.\n\n- A new helper returns true only when the requested stop is `mcp_meta_blockable`, the current step is not the last one, and the gate `tengu_glittery_mitten` is on. A gate is a remote switch Anthropic uses to turn features on for some users.\n\n- If looking up the gate fails with an error, the helper reports `query_mcp_end_turn_stop_hooks` \/ `gate_threw` and returns false.\n\n- A companion helper logs `[end-turn] bookkeeping threw and was skipped:` when its bookkeeping fails, and carries on.\n\n- `query_mcp_end_turn_stop_hooks` was also added to a list of names that looks like a list of behaviour flags.\n\nNothing has been read about `tengu_glittery_mitten`, so whether it is on is unknown.\n\n**Why**\n\nIn practice this may let stop hooks act on end-of-turn requests from MCP servers. When the gate check fails, it is treated as off, and a failure in the extra bookkeeping does not end the turn early.\n\n- Flag `tengu_glittery_mitten`: Not enough to say (read for one account on one subscription tier against v2.1.302; this account: no value returned, anonymous baseline: no value returned, compiled default: on) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Area: Hooks\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: no"}