---
description: Plan development milestones and generate milestone documents with the features for each milestone
---

# Plan Milestones (Milestone Planning Phase)

This command breaks the product down into an ordered set of **milestones** and generates milestone documents under `docs/milestones/`. Each milestone document lists the features it contains, sized so that each feature can be implemented with one `/add-feature` run.

**Planning preferences (optional)**: `$ARGUMENTS` (e.g. `/plan-milestones 3 milestones, MVP in 2 weeks, auth first`)

## How to Run

```bash
claude
> /plan-milestones
> /plan-milestones 3 milestones, MVP first, payments last
```

## Position in the Workflow

```
/setup-project
  ↓
/define-design
  ↓
/generate-app web | flutter | winui3
  ↓
/plan-milestones        ← you are here
  ↓
/add-feature (once per feature, milestone by milestone)
```

## Pre-Run Check

1. Confirm the persistent documents exist. If any of these are missing, stop and tell the user to run `/setup-project` first:
   - `docs/product-requirements.md`
   - `docs/functional-design.md`
   - `docs/architecture.md`
2. Check whether the design files (`docs/design/ui-blueprint.json` etc.) exist. If they do not, warn the user that milestones will be planned without a design spec and suggest running `/define-design` first. Continue only if the user accepts.
3. Create the milestones directory if it does not exist:
   ```bash
   mkdir -p docs/milestones
   ```

## Procedure

### Step 0: Read the Inputs

Read all of the following:

- `docs/product-requirements.md` (especially user stories and priorities)
- `docs/functional-design.md`
- `docs/architecture.md`
- `docs/design/ui-blueprint.json` and `docs/design/design-brief.md` (if present)
- `docs/ideas/*` (if present)
- The planning preferences provided in `$ARGUMENTS` (if any)

### Step 1: Gather Planning Preferences (ask the user once)

If `$ARGUMENTS` does not already answer these, ask the user about the following. If the user does not provide detailed preferences, **propose a sensible default** derived from the PRD priorities and confirm it before proceeding.

- **Number of milestones** (default: 2–4 depending on scope)
- **MVP definition** — what is the smallest product worth releasing?
- **Priorities** — features that must come first or last
- **Constraints** — deadlines, dependencies on external systems, team capacity

Collect the answers in a single round; do not pause again until generation is complete.

### Step 2: Load the Milestone Planning Skill

Load the **milestone-planning skill** (`Skill('milestone-planning')`) for the planning rules and the milestone document template.

### Step 3: Build the Feature Inventory

Derive the complete list of features from the documents:

- Every user story / requirement in the PRD (with its priority)
- Every functional module in the functional design
- Every screen and user action in `ui-blueprint.json` (if present)

Size each feature so it can be implemented with **one `/add-feature` run**. Split anything larger; merge trivial fragments.

### Step 4: Group Features into Milestones

- **Milestone 1 is the MVP**: the smallest set of features that forms a coherent, end-to-end usable product.
- Later milestones build on earlier ones, ordered by priority and dependency (a feature never lands before something it depends on).
- Every feature belongs to **exactly one** milestone. Explicitly park out-of-scope items in a final "Later / Icebox" section of the roadmap.

### Step 5: Create the Roadmap Overview

Create `docs/milestones/roadmap.md` containing:

- A table of all milestones: number, name, goal, feature count, status (`Not started` / `In progress` / `Completed`)
- The ordering rationale (why this sequence)
- A pointer to the current milestone
- The "Later / Icebox" list of consciously deferred items

### Step 6: Create One Document per Milestone

For each milestone, create `docs/milestones/milestone-[NN]-[kebab-case-name].md` (e.g. `milestone-01-mvp.md`) following the milestone-planning skill's template. Each document lists the milestone's features, and each feature includes:

- A checkbox for status tracking (`- [ ]`)
- Description and user value
- Related PRD requirements / user stories
- Affected screens from `ui-blueprint.json` (if a design spec exists)
- Acceptance criteria
- The ready-to-run command: `/add-feature [feature name]`

### Step 7: Consistency Check

Re-read all generated files and confirm:

- Every P0/P1 requirement in the PRD is covered by a milestone (or explicitly parked in the icebox).
- Every feature appears in exactly one milestone.
- Dependencies are ordered correctly across milestones.
- Milestone 1 is a coherent, usable MVP on its own.
- Each feature name works as a `/add-feature` argument.

Fix any inconsistencies found before finishing.

## Completion Criteria

- `docs/milestones/roadmap.md` exists
- One `milestone-[NN]-[name].md` per milestone exists
- Every feature is assigned to exactly one milestone with acceptance criteria

Completion message:
```
"Milestone planning is complete!

Milestone documents created:
✅ docs/milestones/roadmap.md            (overview + status)
✅ docs/milestones/milestone-01-....md   (MVP)
✅ docs/milestones/milestone-NN-....md

Next steps:
- Review docs/milestones/ and adjust priorities if needed
- Run /execute-milestones to implement all milestones one by one autonomously (a separate steering directory is created per milestone)
- Or go feature by feature: run /add-feature [first feature of milestone 1]
- Either way, each feature is marked complete in its milestone document as it finishes
"
```