Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
0Signal: worth watching, 1 to 5
Tool SearchArea: what it touches
Internal ChangesKind: in v2.1.323,
Internal ChangesSection of the release
What
Some tools are held back and only listed by name until Claude needs them. Claude uses the ToolSearch tool to look them up. ToolSearch takes a query, matches it against the held-back tools, and returns each matching tool's full definition so Claude can use it. The wording of this tool's description, as Claude Code sends it to Claude, was edited in this release.
Why
Changing Claude's instructions can change how it behaves. Here the description still explains the same lookup step.
How sure we are
One source agreesOne thing we can check says the same as this entry.
Anthropic's release notes agreeImproved ToolSearch to say when a tool Claude searched for by its short name is already available, instead of only reporting no match
