fix: validate MCP-Protocol-Version header in servlet transports - #1092
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ez-lbz wants to merge 1 commit into
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fix: validate MCP-Protocol-Version header in servlet transports#1092ez-lbz wants to merge 1 commit into
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The streamable HTTP spec requires the server to answer with 400 Bad Request when the client sends an unsupported MCP-Protocol-Version header, and to accept the request when the header is missing (falling back to the negotiated version). The Servlet-based providers never read this header.
This change validates the MCP-Protocol-Version header in doGet, doPost, and doDelete of
HttpServletStreamableServerTransportProviderand in doPost ofHttpServletStatelessServerTransport, rejecting unsupported versions with a 400 JSON error response consistent with the existing error style.Tests cover the version-header matrix (supported version accepted, unsupported version rejected, missing header accepted) across both providers.