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Title: fix(fastmcp): support PEP 604 union return types by MukundaKatta · Pull Request #2599 · modelcontextprotocol/python-sdk · GitHub

Open Graph Title: fix(fastmcp): support PEP 604 union return types by MukundaKatta · Pull Request #2599 · modelcontextprotocol/python-sdk

X Title: fix(fastmcp): support PEP 604 union return types by MukundaKatta · Pull Request #2599 · modelcontextprotocol/python-sdk

Description: The official Python SDK for Model Context Protocol servers and clients - fix(fastmcp): support PEP 604 union return types by MukundaKatta · Pull Request #2599 · modelcontextprotocol/python-sdk

Open Graph Description: Summary define wrapped structured-output fields using Pydantic's explicit required field tuple add regression coverage for FastMCP tools returning container/primitive PEP 604 unions like dict ...

X Description: Summary define wrapped structured-output fields using Pydantic's explicit required field tuple add regression coverage for FastMCP tools returning container/primitive PEP 604 unions like d...

Opengraph URL: https://github.com/modelcontextprotocol/python-sdk/pull/2599

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fix: support PEP 604 structured output unions #2592 https://github.com/modelcontextprotocol/python-sdk/pull/2592
FastMCP crashes when tool return type uses Python 3.10+ A | B | C union syntax #2591 https://github.com/modelcontextprotocol/python-sdk/issues/2591
test(mcpserver): cover PEP 604 union return annotations (#2591) #2906 https://github.com/modelcontextprotocol/python-sdk/pull/2906
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