/writing-plans

name: writing-plans
description: Use when you have a spec or requirements for a multi-step task, before touching code

<!-- Adapted from obra/superpowers writing-plans skill (v5.0.7), MIT-licensed, copyright 2025 Jesse Vincent. Modifications copyright 2026 Joe Amditis. v0.1.0 added a default-on research phase; v0.2.0 reverted that change and made writing-plans a pure consumer of the brainstorming spec (research belongs at the entry-point stage where work originates). See CREDITS.md. -->

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. Proportional tests. 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 superjawn:writing-plans skill to create the implementation plan."

**Context:** This should be run in a dedicated worktree (set up via superjawn:using-git-worktrees).

**Save plans to:** `docs/superpowers/plans/YYYY-MM-DD-<feature-name>.md`

• (User preferences for plan location override this default)

Scope Check

If the spec covers multiple independent subsystems, it should have been broken into sub-project specs during brainstorming. If it wasn't, suggest breaking this into separate plans, one per subsystem. Each plan should produce working, testable software on its own.

File Structure

Before defining tasks, map out which files will be created or modified and what each one is responsible for. This is where decomposition decisions get locked in.

• Design units with clear boundaries and well-defined interfaces. Each file should have one clear responsibility.
• You reason best about code you can hold in context at once, and your edits are more reliable when files are focused. Prefer smaller, focused files over large ones that do too much.
• Files that change together should live together. Split by responsibility, not by technical layer.
• In existing codebases, follow established patterns. If the codebase uses large files, don't unilaterally restructure - but if a file you're modifying has grown unwieldy, including a split in the plan is reasonable.

This structure informs the task decomposition. Each task should produce self-contained changes that make sense independently.

Bite-Sized Task Granularity

**Each step is one action (2-5 minutes):**

• "Run the check that shows the current behavior" - step
• "Implement the minimal change" - step
• "Run the same check and confirm the expected result" - step
• "Commit" - step

Add a new test only when it protects a likely repeat failure, a stable contract, non-obvious logic, or high-impact behavior. Take its expected values from the specification or real data, not from the new code's output.

Plan Document Header

**Every plan MUST start with this header:**

# [Feature Name] Implementation Plan

> **For agentic workers:** REQUIRED SUB-SKILL: Use superjawn:subagent-driven-development (recommended) or superjawn:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.

**Goal:** [One sentence describing what this builds]

**Architecture:** [2-3 sentences about approach]

**Tech Stack:** [Key technologies/libraries]

---

Task Structure

### Task N: [Component Name]

**Files:**
- Create: `exact/path/to/file.py`
- Modify: `exact/path/to/existing.py:123-145`
- Test (only when the task keeps a new test): `tests/exact/path/to/test.py`

**Check:** [The command that proves this task, and why it is the cheapest faithful evidence]

- [ ] **Step 1: Run the check that shows current behavior**

Use an existing test or a focused command when it proves the behavior:

Run: `python -m mypkg.cli convert sample.csv`
Expected: exit 1 with "unsupported column type: date"

When the task keeps a new test, write it first and take the expected value
from the spec or real data:

```python
def test_specific_behavior():
    result = function(input)
    assert result == expected  # expected value from the spec or real data

Run: `pytest tests/path/test.py::test_name -v` Expected: FAIL with "function not defined"

• [ ] **Step 2: Write minimal implementation**

def function(input):
    return expected

• [ ] **Step 3: Run the same check to verify the result**

Run: the same command as Step 1 Expected: the behavior the spec requires (for example, exit 0, or PASS)

• [ ] **Step 4: Commit**

git add src/path/file.py  # add tests/path/test.py only if the task kept a test
git commit -m "feat: add specific feature"

## No Placeholders

Every step must contain the actual content an engineer needs. These are **plan failures**, never write them:
- "TBD", "TODO", "implement later", "fill in details"
- "Add appropriate error handling" / "add validation" / "handle edge cases"
- "Write tests for the above" (without actual test code)
- "Similar to Task N" (repeat the code, the engineer may be reading tasks out of order)
- Steps that describe what to do without showing how (code blocks required for code steps)
- References to types, functions, or methods not defined in any task

## Remember
- Exact file paths always
- Complete code in every step, if a step changes code, show the code
- Exact commands with expected output
- DRY, YAGNI, proportional tests, frequent commits

## Self-Review

After writing the complete plan, look at the spec with fresh eyes and check the plan against it. This is a checklist you run yourself, not a subagent dispatch.

**1. Spec coverage:** Skim each section/requirement in the spec. Can you point to a task that implements it? List any gaps.

**2. Placeholder scan:** Search your plan for