You'll noticeTier: how much it should matter to you
4Useful: my rating, 1 to 5
4Signal: worth watching, 1 to 5
SubagentsArea: what it touches
ImprovementsKind: in v2.1.307,
What probably matters to youSection of the release
Unclear Which writer model, if any, the server names is not known.
What
Claude Code writes short summaries of what a background agent is doing. A background agent is a subagent, a helper Claude starts, working on a task out of view. These summaries can now be written by a separate writer model instead of the agent's own model. This only happens when all of the following hold:
the server's summary settings name a writer model
the summary is the short kind
the agent's own model belongs to the fable or opus family
If a call to the writer model fails, Claude Code stops using it for the rest of the run. Usage reports about skipped and stopped summaries now also record the writer model, the configured writer, and whether the writer failed.
Why
A different model writing the summaries can change what they cost and how good they are. When the server names no writer, the agent's own model is used as before.
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 doubtWhich writer model, if any, the server names is not known.
