Creating a predefined agent with a description kicks off summoning in a
background goroutine. It finishes 10-20 seconds after the create response and
writes SOUL.md, IDENTITY.md, CAPABILITIES.md and the agent frontmatter.
For a client that manages agents as code that is data loss. Such a client
brings its own context files and writes them through agents.files.set as soon
as create returns; summoning lands afterwards and replaces them. Nothing
fails: no error from the API, nothing in the logs, and the agent quietly runs
on generated text instead of the committed role. The only way to avoid it
today is to poll the agent status until it leaves "summoning" — which means
every automation has to know that summoning exists at all.
POST /v1/agents now accepts an optional "summon" field. Absent or true keeps
today's behaviour, so existing clients are unaffected. False creates the agent
active with the seeded template files and starts no LLM call; summoning is
still available afterwards via POST /v1/agents/{id}/resummon.
The status fallback also now resets an explicitly requested "summoning" status
when nothing will summon the agent: that status is only ever cleared by the
summoner, so such an agent would otherwise stay stuck in it forever.
Surface parity: CLI and WS RPC (agents.create) create agents without a
description and never summoned, so they need no flag; the web UI create flow
wants summoning and keeps the default.
