{"version":"2.1.299","anchor":"mcp-interface-version-failure-telemetry","canonical_anchor":"mcp-interface-version-failure-telemetry","heading":"Version failure reports for MCP tool output now record the right cause","tier":"internal","area":"MCP Serve","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299\/e\/mcp-interface-version-failure-telemetry","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299","markdown":"### Version failure reports for MCP tool output now record the right cause\n\nWhen serving tool output over MCP fails on a version check, Claude Code now records the real cause and the minimum version required\n\n**What**\n\nMCP (Model Context Protocol) is how Claude Code talks to outside tools. When serving tool output over MCP fails, Claude Code's usage reporting now records the actual cause of the failure and the minimum interface version that was required. Before, the cause was taken from the wrong value.\n\n**Why**\n\nThis is a fix to what Claude Code reports about these failures.\n\n- Area: MCP Serve\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}