{"version":"2.1.290","anchor":"mcp-failed-connections-record-proxy-connect-status","canonical_anchor":"mcp-failed-connections-record-proxy-connect-status","heading":"Failed MCP connections now record the proxy's status code and skip retries on proxy 403","tier":"notice","area":"MCP","scope":"both","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.290\/e\/mcp-failed-connections-record-proxy-connect-status","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.290","markdown":"### Failed MCP connections now record the proxy's status code and skip retries on proxy 403\n\nMCP connections that fail at a proxy now keep the proxy's HTTP status as proxyConnectStatus, and a 403 there no longer triggers an automatic reconnect\n\n**Unclear.** It is not clear where, if anywhere, this status code is shown to the user.\n\n**What**\n\nMCP servers are outside programs that give Claude Code extra tools. Some networks reach them through a proxy, a middleman server that passes traffic on. When an MCP connection fails because the proxy refused to open a tunnel (error `ERR_PROXY_TUNNEL`), the failure record now includes `proxyConnectStatus`. This is the numeric HTTP status code the proxy sent back. Before, the record held only the name, type, config, error and error code.\n\n- If `proxyConnectStatus` is 403, meaning the proxy forbids the connection, Claude Code no longer treats the failure as worth retrying automatically.\n\n- Connection success and failure records now include `processUptimeAtConnectStartMs`, how long Claude Code had been running when the connection attempt began.\n\n- A new diagnostic record is written after the first list of tools comes back from a server.\n\n- The connection-timeout retry switch `tengu_mcp_connect_timeout_retry` is still checked, and its fallback is still true. Nothing has been read about it or about `tengu_mcp_first_tools_list`.\n\n**Why**\n\nWhen a proxy blocks an MCP server, the reason is now kept with the failure, which makes it easier to see what went wrong. Claude Code also stops retrying a connection the proxy has already forbidden. The new timing data concerns slow MCP startup.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: both\n- Heads-up: no"}