agent-starters

1# Agent Starters
2 
3A named, reusable per-seat starting point. Composes an agent role, startup
4context, optional native session source, and provenance into something a
5user or rig can choose when creating, refreshing, or packaging a seat.
6 
7This registry-backed startup context is distinct from the `rig agent-image`
8surface and from a VM image. See the current behavior below before treating
9optional session provenance as an executable native session source.
10 
11## Use this when
12 
13- Creating a new seat from a known-good starting context.
14- Refreshing a seat with `rig expand` and `starter_ref`.
15- Authoring a new starter (registry entry).
16- Inspecting an existing starter's provenance, freshness, or recommended status.
17- Promoting / deprecating starters in the registry.
18- Composing a starter with a Composable Priming Pack (record manifest id/version, runtime, source session id or transcript path, ready-check evidence, freshness state).
19 
20## Don't use this when
21 
22- You want VM-style deterministic state capture. Starters don't capture VM state.
23- You want to copy provider auth material into a starter. **Starters refer to session sources and context; they do NOT copy credentials.**
24 
25## What makes a starter valuable
26…