{"version":"2.1.299","anchor":"mcp-reconcile-gains-an-up-front-per-server-config-check","canonical_anchor":"mcp-reconcile-gains-an-up-front-per-server-config-check","heading":"MCP servers can be marked failed before Claude Code tries to connect","tier":"internal","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299\/e\/mcp-reconcile-gains-an-up-front-per-server-config-check","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299","markdown":"### MCP servers can be marked failed before Claude Code tries to connect\n\nWhen Claude Code refreshes MCP servers, a check before connecting can now mark a server as failed without trying to reach it\n\n**Unclear.** What the up-front check tests is not known, so which servers it marks as failed is unclear.\n\n**What**\n\nMCP servers are outside programs that give Claude Code extra tools. When your MCP configuration changes, Claude Code goes through the list of servers and brings them up to date. Before, it connected to each server directly.\n\nNow a check runs on each server's configuration first. If the check fails, the server is marked as failed and Claude Code does not try to connect. The same check runs again after a connection is made. A list of extra servers is now also taken into account when deciding what is permitted.\n\n**Why**\n\nIn practice a server can now show as failed without any connection attempt, so a failure is not always a network or server problem.\n\n- Area: MCP\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}