2f481fa352
`session.create` also adopts an already-live session, and the preceding commit newly allows adopting one under the preset it switched to while blank. Its response still echoed `header.agentPreset`, so that adoption answered with the preset the session had just left — contradicting the request it had accepted and the row `session.list` serves for the same session from `resolveSessionPreset()`. The echo now resolves the same way. The `assertPresetUnchanged` parameter doc said `existing` was the preset the session was created under; both callers now pass what it runs. `composeFrom()` was documented as "infallible" and "cannot fail" beside two `@throws`. It has no composition failure mode — no roster read, no mount, no file — but it does reject a caller error, and the wording now says which. The package-level "switched preset" test re-linked to the same preset id, so it could not tell reading the parent's live scope chain from reading its creation header. A second fixture preset makes the switch real. The Web browser lane's subagent goldens gain the preset badge a child now shows, which is the visible consequence of recording its composition. That lane runs only under DSH_EXAMPLE_MODE=lib and was missed before. The Agent Note records two limits found in review: a cold-resumed continuable child joins its parent's current composition rather than the one its header names, and `toolFilter` does not constrain a joined child. The latter is a regression from the agent-plane move rather than anything this change introduces — with the same tools in the global layer the filter applies normally — and is tracked in #2185. Refs #2185
preset/ — per-session agent composition
English | 中文
An agent preset is a directory holding one agent.cordis.yml. Mounting it under an agent's scope context gives that session its own tools and prompt sections while every other live session keeps its own, so one process can run several differently composed agents at once.
| Package | Role | ctx key |
|---|---|---|
agent-presets/ |
Preset vocabulary, filesystem discovery over trusted and user-authored roots, and the guarded per-agent mount | ctx.agentPresets |
persona/ |
The agent persona as a composable row, so a preset can change identity and not only tools | — |
The presets the deployment ships live in apps/cli/config/agent-presets/ — one directory each, and that directory listing is the roster. Naming them here too would be a second list to keep in step, and the first one to fall behind.
The composition split this group assumes: registries and cross-session facilities are process singletons and stay in the host composition, while a preset carries what one agent contributes to them. A preset that names a row publishing a process-global service is rejected at mount rather than allowed to collide with the next session.
Design: the per-session agent-preset note.