fix(mcp): fix SSE transport host binding and remove invalid sse_params kwarg#17
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eddiefleurent wants to merge 1 commit intoHKUDS:mainfrom
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fix(mcp): fix SSE transport host binding and remove invalid sse_params kwarg#17eddiefleurent wants to merge 1 commit intoHKUDS:mainfrom
eddiefleurent wants to merge 1 commit intoHKUDS:mainfrom
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…s kwarg - FastMCP defaults to 127.0.0.1 which prevents remote connections when running SSE transport. Default to 0.0.0.0 and allow override via FASTMCP_HOST / FASTMCP_PORT env vars. - mcp.run() does not accept sse_params kwarg (raises TypeError). Remove it. The --port arg was always a no-op since FastMCP is instantiated at module level before args are parsed; use FASTMCP_PORT env var instead.
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Problem
Two bugs prevent the MCP SSE transport from working:
1.
TypeErroron startupmcp.run()is called withsse_params={"port": args.port}but themcplibrary'sFastMCP.run()does not accept asse_paramskeyword argument, causing an immediate crash:2. SSE server binds to
127.0.0.1(localhost only)FastMCPdefaults tohost="127.0.0.1", so when running SSE transport the server is unreachable from any other machine — making remote MCP clients (Claude Code, Cursor, etc.) unable to connect.Fix
hostandportdirectly to theFastMCPconstructor, defaulting to0.0.0.0:8080with overrides viaFASTMCP_HOST/FASTMCP_PORTenv varssse_paramskwarg frommcp.run()Note: the
--portCLI arg was already a no-op sinceFastMCPis instantiated at module level before args are parsed. Users should useFASTMCP_PORTenv var to configure the port.Usage after fix