Use when you have a spec or requirements for a multi-step task, before touching code

Writing Plans Overview Write comprehensive implementation plans assuming the engineer has zero context for our codebase and questionable taste. Document everything they need to know: which files to touch for each task, code, testing, docs they might need to check, how to test it. Give them the whole plan as bite sized tasks. DRY. YAGNI. TDD. Frequent commits. Assume they are a skilled developer, but know almost nothing about our toolset or problem domain. Assume they don't know good test design very well. Announce at start: "I'm using the writing plans skill to create the implementation plan." Context: Use the project's existing planning location and workflow. A dedicated worktree is useful when code isolation is needed, but planning does not require an unavailable brainstorming skill or authorize implementation. Save plans to: docs/plans/YYYY MM DD <feature name .md Bite Sized Task Granularity Each step is one action (2 5 minutes): "Write the failing test" step "Run it to make sure it fails" step "Implement the minimal code to make the test pass" step "Run the tests and make sure they pass" step "Commit" step Plan Document Header Every plan MUST start with this header: Task Structure python def test specific behavior(): result = function(input) assert result == expected python def function(input): return expected bash git add tests/path/test.py src/path/file.py git commit m "feat: add specific feature" The outer Task Structure template should be copied as Markdown with its inner code blocks intact. Commands and expected outputs are planned checks, not evidence that those checks ran; verify file paths and tool availability against the actual repository. Scale tests and commits to meaningful behavior and the repository policy rather than adding a test or commit mechanically for every edit. Remember Exact file paths always Complete code in plan (not "add validation") Exact commands with expected output Reference relevant skills with @ syntax DRY, YAGNI, TDD, frequent commits Execution Handoff After saving the plan, offer execution choice: "Plan complete and saved to docs/plans/<filename .md . Two execution options: 1. Subagent Driven (this session) I dispatch fresh subagent per task, review between tasks, fast iteration 2. Parallel Session (separate) Open new session with executing plans, batch execution with checkpoints Which approach?" If Subagent Driven chosen: Use an installed subagent driven development procedure if available; otherwise describe the available execution workflow without claiming this dependency is bundled. Stay in this session Fresh subagent per task + code review If Parallel Session chosen: Guide them to open new session in worktree Use an installed executing plans procedure if available; otherwise carry the saved plan and project instructions into the new session. When to Use This skill is applicable to execute the workflow or actions described in the overview. Limitations Use this skill only when the task clearly matches the scope described above. Do not treat the output as a substitute for environment specific validation, testing, or expert review. Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.

writing-plans