When a client that is already attached attaches again with the same ID, Claude Code no longer ignores the call. It merges the new viewport details into what it already stored for that client. The call still reports that no new client was added.
Why
A client that re-attaches with a new viewport has that update kept rather than lost.
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtThe finding does not say what kind of client this is or what its viewport controls.
Anthropic's release notes agreeImproved screen-reader output in /mcp: a disabled server is read as "off" instead of "pending"
