Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
0Signal: worth watching, 1 to 5
ToolsArea: what it touches
Internal ChangesKind: in v2.1.321,
Internal ChangesSection of the release
What
Some of Claude Code's tools are deferred, meaning their full details are only loaded when they are needed. Claude Code keeps track of which of these it has told the model about. It now works out the set of loaded tools only when it needs it, instead of every time. It also skips a check for withdrawn tools when nothing has changed. A usage data field listing the kinds of attachments seen is now taken from the conversation's messages.
Why
This reworks how Claude Code keeps track of which tools it has announced to the model, so it does less repeated work.
