{"version":"2.1.321","anchor":"deferred-tools-delta-lazy-loaded-set-and-attachment-rows","canonical_anchor":"deferred-tools-delta-lazy-loaded-set-and-attachment-rows","heading":"Less repeated work when Claude Code tracks which tools it has announced","tier":"internal","area":"Tools","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.321\/e\/deferred-tools-delta-lazy-loaded-set-and-attachment-rows","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.321","markdown":"### Less repeated work when Claude Code tracks which tools it has announced\n\nClaude Code now works out its loaded tools only when needed and skips a check when nothing has changed\n\n**What**\n\nSome 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 It also skips a check for withdrawn tools when nothing has changed.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.\n\n**Why**\n\nThis reworks how Claude Code keeps track of which tools it has announced to the model, so it does less repeated work.\n\n- Area: Tools\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 0\/5\n- Scope: individual\n- Heads-up: no"}