{"version":"2.1.236","anchor":"mcp-protocol-auto-negotiation-now-covers-the-ccr-proxy-trans","canonical_anchor":"mcp-protocol-auto-negotiation-now-covers-the-ccr-proxy-trans","heading":"MCP protocol auto-negotiation now covers the ccr-proxy transport, off by default","tier":"soon","area":"MCP","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.236\/e\/mcp-protocol-auto-negotiation-now-covers-the-ccr-proxy-trans","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.236","markdown":"### MCP protocol auto-negotiation now covers the ccr-proxy transport, off by default\n\nThe ccr-proxy MCP transport can negotiate protocol versions, but stays on legacy unless a flag is turned on.\n\n**What**\n\nThe `ccr-proxy` MCP transport used to fall through to the legacy branch alongside sse, ws and ide. It now has its own check gated on `tengu_mcp_protocol_negotiation_ccr`: with the flag on it negotiates in auto mode with a probe, and with it off it stays on legacy exactly as before.\n\n**Details**\n\n- Fallback is false, so absent a server value nothing changes.\n\n**Evidence**\n\n`tengu_mcp_protocol_negotiation_ccr`\n\n- Flag `tengu_mcp_protocol_negotiation_ccr`: Not enough to say (read for one account on one subscription tier against v2.1.236; this account: no value returned, anonymous baseline: no value returned, compiled default: off)\n- Area: MCP\n- Tier: Nothing to try yet\n- Useful: 2\/5\n- Signal: 3\/5\n- Present in the build but not switched on"}