writing-plans
Writing Plans
Overview
Write implementation plans for an engineer who has not seen this codebase or the agreed requirements and decision sources. Assume they write idiomatic code in the project's language once they know the exact interface and the exact test, and that they will make a reasonable choice wherever the plan leaves one open. What they cannot know is what you decided: which files, which names and signatures, which values from the agreed requirements and decision sources, which tests prove each task. Document those. Give them the whole plan as bite-sized tasks. DRY. YAGNI. TDD. Frequent commits.
Announce at start: "I'm using the writing-plans skill to create the implementation plan."
Context: For heavy work an isolated worktree may have been created via the using-git-worktrees skill; small work runs inline on the current branch.
Save plans to: docs/plans/NNNN-<feature-name>.md (next number in sequence)
Scope Check
If the agreed work covers independently deliverable subsystems, recommend separate numbered plans with their own outcomes and acceptance criteria. Use applicable decision sources; separate feature specs are optional.