aw-create-plan

# Create Plan Artifact Generate `.agent/{branch-name}/plan.md` — the planner→executor handoff document — alongside `checks.yaml`, the executable acceptance checks derived from the Acceptance Criteria. **A new Claude session MUST be able to execute from `plan.md` alone without the original conversation.** **`plan.md` is a handoff artifact, not an exhaustive knowledge base.** Keep it lean (see the Core/Extended tiering in Step 2). `checks.yaml` is the **living contract** — it is re-derived on every iteration (statuses reset to `pending`) and self-validates against reality on every executor loop, so it does not go stale the way prose does. When something is unclear, prefer asking the still-running planner agent (or the user) over bloating the document to answer every future question. ## Snapshot mode (opt-in) **By default this skill writes only `plan.md`** (overwritten in place each iteration; the `version:` frontmatter is the iteration counter). `.agent/` is gitignored per-developer scratch, so immutable `plan.vN.md` snapshot chains are **not** written by default — they are rarely re-read and cost a redundant write per iteration, with no measured effect on task success ([research §5.4](../autonomous-workflow/references/anthropic-architecture-research.md#54-what-is-not-evidence-backed)). **Opt in to snapshots** with `Skill("aw-create-plan", "snapshot")` — then the skill also writes an immutable `plan.v{N}.md` alongside `plan.md` (`plan.v1.md`, `plan.v2.md`, … as history) f...