Unclear What the two new checks look at, and so when they stop a sign-in, is not known.
What
MCP servers are outside programs that give Claude extra tools, and some need you to sign in through OAuth, a standard sign-in flow. Before that sign-in begins, Claude Code now runs two extra checks using the server's name and settings.
If one of these checks fails after the sign-in has been cancelled, Claude Code reports that the sign-in was cancelled rather than the check's own error.
Why
MCP sign-in can now stop earlier, before any browser step.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
What the two new checks look at, and so when they stop a sign-in, is not known.