A subagent is a child Claude that a session starts with its Agent tool. It
has its own transcript, runs to completion, and cannot be resumed. Switchboard
indexes subagent transcripts and shows them under the session that started
them.
A session with subagents has a ▶ N subagents caret; the choice to expand it is remembered per session. Under it, each subagent row shows:
- a pill with the subagent's type (
subwhen the type is unknown), and a left border in the type's colour (exploregreen,planindigo,implementorange,reviewlight blue,testred, any other type grey — the type name is compared case-insensitively); - its status icon (below);
- its description, or its summary;
- its message count.
The first 10 subagents of a session are listed, then + N more.
A subagent follows its parent's archive state without being archived itself: while the parent is archived its subagents are hidden with it, Show archived sessions shows them nested under the archived parent, and unarchiving the parent brings them back.
Subagents whose parent session cannot be found — its transcript was deleted, say — are listed in an Orphan subagents group at the bottom of the project, collapsed by default. A subagent of an archived parent is never an orphan.
Subagent rows have no pin, rename, stop, fork, archive or delete buttons. Deleting a session deletes its subagent transcripts with it — see Session browser.
The Sessions tab's search covers subagent transcripts. A session whose only match is in one of its subagents is listed, with that subagent.
Clicking a subagent row opens its transcript, read-only, in the transcript
viewer: messages, tool calls and results. It does not run claude --resume. A
Resume in terminal anyway button at the top resumes it for the rare case
where that is wanted.
The session's own status icon has three shapes for "something is running", distinguished by movement and hue:
| Icon | Meaning |
|---|---|
| Light-blue braille spinner | The session is working; no subagent runs under it |
| The same spinner, violet | The session is working, and at least one subagent runs under it |
| Static violet ⠿ | The session is at its prompt; subagents still run under it |
The violet spinner says the session is busy while agents run. It does not say the session is waiting for them: the CLI reports one busy state on its terminal title and never signals "waiting for background agents", so the two cannot be told apart. The session's higher-priority states — needs attention, response ready — replace the icon (see Status indicators). The three shapes show whether the subagent list is expanded or not.
Subagent activity is detected from the subagent transcripts on disk — for local sessions, for sessions started outside Switchboard, and for sessions on remote hosts. A subagent whose transcript stops growing is marked finished after a stability window; one that grows again is shown running again.
The grid shows running subagents as coloured pills on the parent's card.