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Title: fix: return HTTP 404 for unknown session IDs instead of 400 by max-rousseau · Pull Request #1808 · modelcontextprotocol/python-sdk · GitHub

Open Graph Title: fix: return HTTP 404 for unknown session IDs instead of 400 by max-rousseau · Pull Request #1808 · modelcontextprotocol/python-sdk

X Title: fix: return HTTP 404 for unknown session IDs instead of 400 by max-rousseau · Pull Request #1808 · modelcontextprotocol/python-sdk

Description: The official Python SDK for Model Context Protocol servers and clients - fix: return HTTP 404 for unknown session IDs instead of 400 by max-rousseau · Pull Request #1808 · modelcontextprotocol/python-sdk

Open Graph Description: Summary Fixes incorrect HTTP status code returned by StreamableHTTPSessionManager when receiving requests with unknown or expired session IDs. Per the MCP Streamable HTTP transport specification, s...

X Description: Summary Fixes incorrect HTTP status code returned by StreamableHTTPSessionManager when receiving requests with unknown or expired session IDs. Per the MCP Streamable HTTP transport specification, s...

Opengraph URL: https://github.com/modelcontextprotocol/python-sdk/pull/1808

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fix: return HTTP 404 for unknown session IDs instead of 400https://github.com/modelcontextprotocol/python-sdk/pull/1808/commits/4aaf4ad9335633317a11cd4c5a52e55feaeb45fd
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refactor: use typed models and add test for session 404 responsehttps://github.com/modelcontextprotocol/python-sdk/pull/1808/commits/75b142bcc325b4fcff5c10befa8c31ac5918e6f0
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StreamableHTTPSessionManager returns 400 instead of 404 for unknown session ID https://github.com/modelcontextprotocol/python-sdk/issues/1727
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