fix: use z.string() for attachment content to fix Gemini compatibility#14
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MaxwellCalkin wants to merge 1 commit intoagentmail-to:mainfrom
Open
fix: use z.string() for attachment content to fix Gemini compatibility#14MaxwellCalkin wants to merge 1 commit intoagentmail-to:mainfrom
MaxwellCalkin wants to merge 1 commit intoagentmail-to:mainfrom
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z.base64() produces a contentEncoding field in the JSON Schema output which Google Gemini's function calling API does not support, causing tool registration to fail for send_message, reply_to_message, and forward_message tools. Fixes agentmail-to/agentmail-mcp#8 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
z.base64()withz.string()for the attachmentcontentfield in the schemaz.base64()produces acontentEncoding: "base64"field in the JSON Schema output, which Google Gemini's function calling API does not supportsend_message,reply_to_message, andforward_messagetools when used with any Gemini modelThe description
'Base64 encoded content'is preserved so consumers still know to provide base64 data.Fixes agentmail-to/agentmail-mcp#8
Test plan
🤖 Generated with Claude Code
Summary by cubic
Switch the attachment content field from z.base64() to z.string() to avoid emitting contentEncoding in the JSON Schema, which Gemini’s function-calling API does not support. This unblocks MCP tool registration (send_message, reply_to_message, forward_message) with Gemini, while keeping the "Base64 encoded content" description so clients still send base64 strings.
Written for commit 342d8dc. Summary will update on new commits.