{"version":"2.1.312","anchor":"tool-use-start-hook-removed-from-streaming","canonical_anchor":"tool-use-start-hook-removed-from-streaming","heading":"An early step at the start of each tool call was removed","tier":"internal","area":"Elsewhere","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.312\/e\/tool-use-start-hook-removed-from-streaming","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.312","markdown":"### An early step at the start of each tool call was removed\n\nClaude Code no longer runs an extra early step when a tool call begins to arrive in the streamed reply\n\n**What**\n\nA tool call is a request from Claude to use one of its tools, such as reading a file or running a command. While Claude's reply is still arriving piece by piece, Claude Code used to run an extra step as soon as a tool call began. It no longer does.\n\n**Why**\n\nOne early side effect at the start of a tool call is gone. The tool call itself still runs as before.\n\n- Area: Elsewhere\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}