ralph（Ralph 助手）

Ralph PRD Converter

Converts existing PRDs to prd.json and sets up an isolated git worktree for autonomous execution.

The Job

1. Take a PRD (markdown file or text) and convert it to prd.json
2. Create a git worktree for Ralph to work in
3. Save prd.json and initialize progress tracking in the worktree

Output Format

{
  "project": "[Project Name]",
  "branchName": "ralph/[feature-name-kebab-case]",
  "description": "[Feature description from PRD title/intro]",
  "userStories": [
    {
      "id": "US-001",
      "title": "[Story title]",
      "description": "As a [user], I want [feature] so that [benefit]",
      "acceptanceCriteria": [
        "Criterion 1",
        "Criterion 2",
        "Typecheck passes"
      ],
      "priority": 1,
      "passes": false,
      "notes": ""
    }
  ]
}

Story Size: The Number One Rule

Each story must be completable in ONE Ralph iteration (one context window).

Ralph spawns a fresh Amp instance per iteration with no memory of previous work. If a story is too big, the LLM runs out of context before finishing and produces broken code.

Right-sized stories:

• Add a database column and migration
• Add a UI component to an existing page
• Update a server action with new logic
• Add a filter dropdown to a list

Too big (split these):

• "Build the entire dashboard" - Split into: schema, queries, UI components, filters
• "Add authentication" - Split into: schema, middleware, login UI, session handling
• "Refactor the API" - Split into one story per endpoint or pattern

Rule of thumb: If you cannot describe the change in 2-3 sentences, it is too big.

Story Ordering: Dependencies First

Stories execute in priority order. Earlier stories must not depend on later ones.

Correct order:

1. Schema/database changes (migrations)
2. Server actions / backend logic
3. UI components that use the backend
4. Dashboard/summary views that aggregate data

Wrong order:

1. UI component (depends on schema that does not exist yet)
2. Schema change

Acceptance Criteria: Must Be Verifiable

Each criterion must be something Ralph can CHECK, not something vague.

Good criteria (verifiable):

• "Add status column to tasks table with default 'pending'"
• "Filter dropdown has options: All, Active, Completed"
• "Clicking delete shows confirmation dialog"
• "Typecheck passes"
• "Tests pass (use vitest-testing skill)"
• "Write tests using vitest-testing skill"

Bad criteria (vague):

• "Works correctly"
• "User can do X easily"
• "Good UX"
• "Handles edge cases"

Always include as final criterion:

"Typecheck passes"

For stories with testable logic, also include:

"Tests pass (use vitest-testing skill)"

For stories that change UI, also include:

"Verify in browser using dev-browser skill"

Frontend stories are NOT complete until visually verified. Ralph will use the dev-browser skill to navigate to the page, interact with the UI, and confirm changes work.

Conversion Rules

1. Each user story becomes one JSON entry
2. IDs: Sequential (US-001, US-002, etc.)
3. Priority: Based on dependency order, then document order
4. All stories: passes: false and empty notes
5. branchName: Derive from feature name, kebab-case, prefixed with ralph/
6. Always add: "Typecheck passes" to every story's acceptance criteria

Splitting Large PRDs

If a PRD has big features, split them:

Original:

"Add user notification system"

Split into:

1. US-001: Add notifications table to database
2. US-002: Create notification service for sending notifications
3. US-003: Add notification bell icon to header
4. US-004: Create notification dropdown panel
5. US-005: Add mark-as-read functionality
6. US-006: Add notification preferences page

Each is one focused change that can be completed and verified independently.

Example

Input PRD:

# Task Status Feature

Add ability to mark tasks with different statuses.

## Requirements
- Toggle between pending/in-progress/done on task list
- Filter list by status
- Show status badge on each task
- Persist status in database

Output prd.json:

{
  "project": "TaskApp",
  "branchName": "ralph/task-status",
  "description": "Task Status Feature - Track task progress with status indicators",
  "userStories": [
    {
      "id": "US-001",
      "title": "Add status field to tasks table",
      "description": "As a developer, I need to store task status in the database.",
      "acceptanceCriteria": [
        "Add status column: 'pending' | 'in_progress' | 'done' (default 'pending')",
        "Generate and run migration successfully",
        "Typecheck passes",
        "Tests pass (use vitest-testing skill)"
      ],
      "priority": 1,
      "passes": false,
      "notes": ""
    },
    {
      "id": "US-002",
      "title": "Display status badge on task cards",
      "description": "As a user, I want to see task status at a glance.",
      "acceptanceCriteria": [
        "Each task card shows colored status badge",
        "Badge colors: gray=pending, blue=in_progress, green=done",
        "Typecheck passes",
        "Verify in browser using dev-browser skill"
      ],
      "priority": 2,
      "passes": false,
      "notes": ""
    },
    {
      "id": "US-003",
      "title": "Add status toggle to task list rows",
      "description": "As a user, I want to change task status directly from the list.",
      "acceptanceCriteria": [
        "Each row has status dropdown or toggle",
        "Changing status saves immediately",
        "UI updates without page refresh",
        "Typecheck passes",
        "Verify in browser using dev-browser skill"
      ],
      "priority": 3,
      "passes": false,
      "notes": ""
    },
    {
      "id": "US-004",
      "title": "Filter tasks by status",
      "description": "As a user, I want to filter the list to see only certain statuses.",
      "acceptanceCriteria": [
        "Filter dropdown: All | Pending | In Progress | Done",
        "Filter persists in URL params",
        "Typecheck passes",
        "Verify in browser using dev-browser skill"
      ],
      "priority": 4,
      "passes": false,
      "notes": ""
    }
  ]
}

Worktree Setup

After generating prd.json, create an isolated git worktree for Ralph to work in.

1. Create the worktree

# From the repo root — create worktree with a new branch from main
git worktree add .claude/worktrees/ralph/<feature-name> -b ralph/<feature-name> main

Where <feature-name> is the kebab-case feature name (the part after ralph/ in branchName).

2. Install dependencies and pull env

cd .claude/worktrees/ralph/<feature-name>
bun install
bun run env:pull

3. Save files into the worktree

Save prd.json to the worktree's ralph directory:

.claude/worktrees/ralph/<feature-name>/scripts/ralph/prd.json

Initialize progress.txt in the worktree:

.claude/worktrees/ralph/<feature-name>/scripts/ralph/progress.txt

With content:

# Ralph Progress Log
Started: <current date>
---

4. Tell the user how to run Ralph

# From the main repo root
scripts/ralph/ralph-tree.sh ralph/<feature-name>

# With options
scripts/ralph/ralph-tree.sh ralph/<feature-name> --tool claude 15

Checklist Before Saving

Before writing prd.json, verify:

• Each story is completable in one iteration (small enough)
• Stories are ordered by dependency (schema to backend to UI)
• Every story has "Typecheck passes" as criterion
• UI stories have "Verify in browser using dev-browser skill" as criterion
• Acceptance criteria are verifiable (not vague)
• No story depends on a later story
• Worktree created at .claude/worktrees/ralph/<feature-name>/
• bun install and bun run env:pull run in worktree
• prd.json saved into the worktree's scripts/ralph/
• progress.txt initialized in the worktree