What
When a message references a file using an @-mention but that file was never actually read, Claude Code now renders it distinctly as 'Referenced (not read)', listing the mentioned names.
Why
This makes it clear when a file you mentioned wasn't actually opened and read into context, instead of leaving that ambiguous.
Names in the bundle@mention
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Added since
A small documentation edit on Use Claude Tag in a group DM touched a line naming @mention after this was published.
Select **Confirm** within 30 minutes. The card changes to a line that names the person who confirmed and says Claude now replies only when @mentioned.claude-tag/users/group-dms see the edit
Confirmed since
Anthropic's documentation has since written up @mention, on Claude Code in Slack.
In Code + Chat routing mode, when you mention @Claude in a Slack channel or thread, Claude automatically detects whether your message is a coding task. Coding tasks go to a Claude Code cloud session. Anything else gets a regular chat reply…slack see the edit
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agrees
Anthropic's documentation has since written up @mention, on Claude Code in Slack.