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Title: fix: support PEP 604 structured output unions by he-yufeng · Pull Request #2592 · modelcontextprotocol/python-sdk · GitHub

Open Graph Title: fix: support PEP 604 structured output unions by he-yufeng · Pull Request #2592 · modelcontextprotocol/python-sdk

X Title: fix: support PEP 604 structured output unions by he-yufeng · Pull Request #2592 · modelcontextprotocol/python-sdk

Description: The official Python SDK for Model Context Protocol servers and clients - fix: support PEP 604 structured output unions by he-yufeng · Pull Request #2592 · modelcontextprotocol/python-sdk

Open Graph Description: Summary wrap FastMCP structured output annotations with Pydantic's explicit (annotation, ...) field form add regression coverage for dict | list | str return annotations Fixes #2591. To verif...

X Description: Summary wrap FastMCP structured output annotations with Pydantic's explicit (annotation, ...) field form add regression coverage for dict | list | str return annotations Fixes #2591. To v...

Opengraph URL: https://github.com/modelcontextprotocol/python-sdk/pull/2592

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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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