mcp: ignore Mcp-Session-Id on 2026-07-28 sessions - #1222
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2026-07-28 removed protocol-level sessions (SEP-2567), so a client must not echo an Mcp-Session-Id even if a non-compliant server sends one. Drop the session ID once the negotiated version is known to be modern, so it is not sent on later requests or used to terminate the session on close.
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| // Protocol-level sessions were removed in 2026-07-28 (SEP-2567): a client | ||
| // must not echo an Mcp-Session-Id, so drop one that the initial response | ||
| // adopted before the negotiated version was known. | ||
| if state.InitializeResult != nil && | ||
| state.InitializeResult.ProtocolVersion >= protocolVersion20260728 { | ||
| c.sessionID = "" | ||
| } |
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this is a duplicate of the lines below
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Thanks, good catch. Consolidated it so the version check is computed once and reused for both the session-id reset and the standalone-SSE branch.
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2026-07-28 removed protocol-level sessions (SEP-2567), so the client must not echo an Mcp-Session-Id even if a non-compliant server sends one. Drop the session ID once the negotiated version is known to be modern, so it is not sent on later requests or used for a DELETE on close.
Added a regression test covering a modern session where the server sends a session ID; the client must not echo it on later requests.
Closes #1028