Under the hood
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Chrome file uploads can now skip local prep under a Cowork-specific condition.
Claude-in-Chrome file uploads via the file_upload/browser_batch MCP tool can now skip local input preparation entirely, using a new passThroughChromeFileUploadInput handler instead of the existing prepareChromeFileUploadInput. This pass-through path only kicks in when the MCP server isn't stdio-based, the process isn't CLAUDE_CODE_REMOTE, and CLAUDE_CODE_IS_COWORK is set.
Names in the bundleCLAUDE_CODE_IS_COWORK
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Anthropic's release notes agree
Fixed Claude in Chrome file_upload failing with "paths: expected array, received undefined" in local Cowork sessions run from the Claude…