RunStepService Walkthrough

RunStepService is Hexi's orchestration use case.

Responsibilities

1. ensure .hexi state exists,
2. load model config and policy,
3. emit start/progress events,
4. gather bounded workspace context,
5. request and parse ActionPlan,
6. execute actions through ports,
7. emit review and terminal done.

Failure behavior

• plan parse errors emit error then terminal done.
• action execution errors emit error, review, then terminal done.

Why this shape matters

• orchestration remains in core,
• side effects stay in adapters,
• behavior is testable with fake ports.