design-solution

Produce docs/specs/<YYYY-MM-DD>-<feature>/design.md: HOW the approved requirements get satisfied. Start from the skill set's templates/design.md. Resolve pack seeds in this order, first path that exists: (1) templates/ beside this SKILL.md, (2) ${CLAUDE_PLUGIN_ROOT}/templates when that variable is set, (3) ../../../templates relative to this SKILL.md. Every heading in it is a REQUIRED slot. The requirements file is your input contract — read it fully first.

Create a todo per step (1, 2, 2b, 3, 4) before starting, and complete them in order — this skill owns its own list, distinct from specify-behavior' upstream and plan-tasks's downstream. Check each off only when its Done when: is met.

Step 1: Context and decisions

Explain in 2–4 paragraphs what exists today, which constraint shapes the approach, and the alternative that constraint rules out. To learn "what exists today" without flooding this context, dispatch a scan subagent to map the touched surface — the seams the design will name: current signatures, data shapes, save/load paths — returning a digest file (.skills/<CODE>/scan.md (or .skills/_pending-/scan.md before CODE)), not raw source. Design against the digest; pull a specific file into context only when a decision hinges on its exact contents. (No subagents? Read the surface directly, but only the parts a decision needs.)