{"version":"2.1.319","anchor":"deferred-tools-announcement-reworked-removal-by-cause-and-d","canonical_anchor":"deferred-tools-announcement-reworked-removal-by-cause-and-d","heading":"Model told more precisely when deferred tools are removed or restored","tier":"internal","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319\/e\/deferred-tools-announcement-reworked-removal-by-cause-and-d","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319","markdown":"### Model told more precisely when deferred tools are removed or restored\n\nThe deferred-tools update now splits removals by cause, restores denied tools, and can mark denials even when its flag is off\n\n**Unclear.** Whether the split by cause and the restoring of denied tools are switched on by default is not stated.\n\n**What**\n\nSome tools are made available to the model only partway through a session (deferred tools). Claude Code sends the model an update when that set changes, and this release reworks it:\n\n- The update can now report `removedForOtherCause` and `restoresDeferred`. Before, withdrawn tools came only from revoked tools, and removals were not split by cause.\n\n- Tools withdrawn because they were denied can be restored. Each withdrawn tool records whether it goes back to deferred (`restoresDeferred`), and a restored name also clears its entry for running again.\n\n- Tools marked `enableToolsUnlisted` are held back from the added lines.\n\n- The `deniedLead` marker for denied tools used to depend only on the flag `tengu_composed_treehouse`, whose fallback is false. It is now also set whenever the session's `tellsDenies` is true, even if the flag is off. How `tellsDenies` is computed was not traced.\n\nFor `tengu_composed_treehouse`, the flag server returned off for this site's account and for the anonymous baseline, in readings not taken under this release. Nothing has been read about `tengu_deferred_tools_pool_change`.\n\n**Why**\n\nThis changes what the model is told when tools disappear or are denied. The denial marker may now appear for users who do not have the flag.\n\n- Area: MCP\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}