{"version":"2.1.310","anchor":"auth-failed-mcp-tool-listing-marks-discoveryauthfailure","canonical_anchor":"auth-failed-mcp-tool-listing-marks-discoveryauthfailure","heading":"MCP servers that refuse sign-in while listing tools are now flagged","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.310\/e\/auth-failed-mcp-tool-listing-marks-discoveryauthfailure","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.310","markdown":"### MCP servers that refuse sign-in while listing tools are now flagged\n\nAny MCP server that gives an authentication error while listing its tools is now marked as having failed sign-in\n\n**What**\n\nMCP servers are outside programs that give Claude Code extra tools. When Claude Code asks a server for its list of tools and the server answers with an authentication error (it refuses because Claude Code is not signed in or its credentials were rejected), Claude Code now marks that server as having failed sign-in during discovery. Previously only one case was marked: a rejected credential on the claude.ai proxy server.\n\n**Why**\n\nThis may change how a failed MCP server shows up, for example as one that needs you to sign in again rather than one that simply failed.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}