Comet Phase 3: Plan and Build

On first entering a phase, handing off to a new Agent, or restoring context, read and follow Task Context and Artifact Language. Prefer the current continuation or claimed Action's contextRequest; do not retrieve repeatedly during uninterrupted work in the same phase.

After entry returns layout, follow comet-classic/reference/classic-layout.md to bind each logical root to its directory. Do not reload the protocol if it is already in context. Use the adapter for all OpenSpec CLI calls and the bound <classic-*> roots for paths; do not run an extra root show first.

SDK Run path

On first entering the current SDK phase, handing off to a new Agent, or restoring context, read phase entry and recovery and the current phase's section in that reference. Reuse them when already available and still valid in this session. Continue with the phase below; recovery routes based on nextAction.kind apply only to older responses without a continuation mode.

Reuse the current valid result's agent.continuation / data.nextAction and bound state. Run comet state next <change-name> --json only on a cold resume, after external state changes, or when necessary information is missing. For data.runtimeFormat: sdk, advance only this Run; the implementation methods, plan content, and reviews are in SDK execution methods; submit state and evidence through this section. data.phase must be build. Reuse valid layout and configuration already in context; use comet state check <change-name> build --json only when they are missing. For nextAction.kind: reconcile, run comet state check <change-name> build --recover --json and establish the original outcome before repeating external work.