René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"SEP-2243: HTTP Header Standardization for Streamable HTTP Transport","articleBody":"## Description\n\nPer [SEP-2243 (HTTP Standard Headers)](https://github.com/modelcontextprotocol/modelcontextprotocol/blob/main/seps/2243-http-standard-headers.md), MCP clients MUST send the following HTTP headers on POST requests:\n\n- `Mcp-Method`: Set to the JSON-RPC `method` value from the request body (REQUIRED on every POST)\n- `Mcp-Name`: Set from `params.name` (for tools/call, prompts/get) or `params.uri` (for resources/read, resources/subscribe, resources/unsubscribe) when present\n\n## Context\n\nThe cxxmcp (C++ SDK) conformance testing revealed that the official conformance test suite's reference client (TypeScript SDK) does not send these headers, making the conformance suite self-contradictory. See:\n- [typescript-sdk#2176](https://github.com/modelcontextprotocol/typescript-sdk/issues/2176) — TypeScript SDK bug report\n- [conformance#323](https://github.com/modelcontextprotocol/conformance/issues/323) — Conformance suite self-contradiction\n- [typescript-sdk#2178](https://github.com/modelcontextprotocol/typescript-sdk/pull/2178) — Fix PR for TypeScript SDK\n\n## Impact\n\nServers that enforce SEP-2243 (reject missing `Mcp-Method` with HTTP 400) are incompatible with clients that don't send these headers. This affects cross-SDK interoperability.\n\n## Request\n\nPlease implement `Mcp-Method` and `Mcp-Name` header support per SEP-2243 to ensure cross-SDK compatibility.","author":{"url":"https://github.com/caomengxuan666","@type":"Person","name":"caomengxuan666"},"datePublished":"2026-05-29T14:00:30.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/990/java-sdk/issues/990"}