When MCP sign-in fails, Claude Code can hand off to claude.ai to connect the server

What

MCP servers are outside services that give Claude extra tools. Some ask you to sign in through OAuth, a standard browser-based sign-in. When that sign-in fails, Claude Code can now offer to connect the server through claude.ai instead, where it becomes a claude.ai connector.

• In the /mcp menu, the server dialog can show a 'Connect on claude.ai' option for HTTP servers. It is selected by default when present. It opens your browser to a connect page, then checks with claude.ai ('Checking with claude.ai…') whether the server is now connected there, and tells you the tools will load as a claude.ai connector the next time Claude Code starts.
• In claude mcp login, if the OAuth flow fails, Claude Code now checks for the same handoff. It can print the connect link and optionally open it, and it clears saved sign-in data for the connector names. Before, the command only printed 'Couldn't complete authentication'.

Why

If signing in to an MCP server from your own machine does not work, you now have another route: connect it on claude.ai and pick up its tools on your next start, instead of hitting a dead end.