RALPH — Autonomous PRD Implementation

RALPH (Repeated Autonomous Loop for PRD Handling) implements a PRD stored as GitHub issues — autonomously, with TDD, and a code review gate after every iteration.

The Pipeline

This skill is the execution engine for a 4-step coding workflow:

Step	Command	What It Does
1	/grill-me	Stress-test your idea with relentless questions before building
2	/write-a-prd	Turn the idea into an engineering spec (PRD) as a GitHub issue
3	/prd-to-issues	Break the PRD into vertical-slice sub-issues with dependencies
4	/ralph	Implement each sub-issue autonomously with TDD + code review

Steps 1-3 use skills from Matt Pocock. Install them:

npx skills@latest add mattpocock/skills -s grill-me
npx skills@latest add mattpocock/skills -s write-a-prd
npx skills@latest add mattpocock/skills -s prd-to-issues

Setup

After installing this skill, copy the RALPH scripts to your project root:

mkdir -p ralph
cp .agents/skills/ralph/afk-ralph.sh ralph/
cp .agents/skills/ralph/ralph-once.sh ralph/
cp .agents/skills/ralph/prompt.md ralph/
cp .agents/skills/ralph/review-prompt.md ralph/
chmod +x ralph/*.sh

Requirements

• Claude Code CLI
• GitHub CLI (gh) — authenticated
• Docker Desktop with Sandbox support (AFK mode only)
• Git

Usage

/ralph <issue-number> — Human-in-the-loop (start here)

./ralph/ralph-once.sh 42

Implements one sub-issue from PRD #42, then stops for your review. Run again for the next one. Recommended for your first few iterations.

/ralph <issue-number> afk [max-iterations] — Autonomous

./ralph/afk-ralph.sh 42 20

Runs up to 20 iterations inside a Docker sandbox. Each iteration: implement one sub-issue, run tests, commit, code review, close issue. When all sub-issues are done, pushes the branch and opens a PR.

Instructions

When the user invokes this skill:

1. Parse arguments: first is the PRD issue number (required), second is mode (once or afk, default once), third is max iterations for afk mode (default 20)
2. If no issue number is provided, ask for it
3. Verify ralph/ directory exists at the project root. If not, guide the user through setup (copy scripts from .agents/skills/ralph/)
4. For once mode (default):

   ./ralph/ralph-once.sh <issue-number>
   

5. For afk mode:

   ./ralph/afk-ralph.sh <issue-number> <max-iterations>
   

6. Report the result when complete

How It Works

1. Scripts fetch the PRD issue and all sub-issues via gh CLI
2. Sub-issues are found by searching for Parent PRD #<number> in their body
3. Each iteration: Claude picks one open, unblocked sub-issue and implements it using TDD
4. Tests must pass before every commit (auto-detected from project config)
5. After committing, a code review gate checks for bugs, logic errors, security issues, and architecture violations
6. Claude closes the sub-issue on GitHub with a comment linking the commit
7. Loop continues until all sub-issues are closed

Sub-Issue Format

Sub-issues created by /prd-to-issues follow this format:

## Parent PRD
#42

## What to build
Description of the work...

## Acceptance criteria
- [ ] Criterion 1
- [ ] Criterion 2

## Blocked by
- #43

Tips

• Start with /ralph (once mode). Validate the first iteration before going AFK.
• Keep sub-issues small. One logical change per sub-issue prevents context rot.
• Use /grill-me first. The more you think before coding, the better RALPH performs.
• Use blocked-by. Declare dependencies so RALPH works in the right order.