Supported Agents

Open Ralph Wiggum works with multiple AI coding agents. Switch between them using the --agent flag:

| Agent | Flag | Description | |-------|------|-------------| | Claude Code | --agent claude-code | Anthropic's Claude Code CLI for autonomous coding | | Codex | --agent codex | OpenAI's Codex CLI for AI-powered development | | Copilot CLI | --agent copilot | GitHub Copilot CLI for agentic coding | | OpenCode | --agent opencode | Default agent, open-source AI coding assistant |

# Use Claude Code
ralph "Build a REST API" --agent claude-code --max-iterations 10

# Use OpenAI Codex
ralph "Create a CLI tool" --agent codex --max-iterations 10

# Use Copilot CLI
ralph "Refactor the auth module" --agent copilot --max-iterations 10

# Use OpenCode (default)
ralph "Fix the failing tests" --max-iterations 10

What is Open Ralph Wiggum?

Open Ralph Wiggum implements the Ralph Wiggum technique — an autonomous agentic loop where an AI coding agent (Claude Code, Codex, or OpenCode) receives the same prompt repeatedly until it completes a task. Each iteration, the AI sees its previous work in files and git history, enabling self-correction and incremental progress.

This is a CLI tool that wraps any supported AI coding agent in a persistent development loop. No plugins required — just install and run.

# The essence of the Ralph loop:
while true; do
  claude-code "Build feature X. Output <promise>DONE</promise> when complete."  # or codex, opencode
done

Why this works: The AI doesn't talk to itself between iterations. It sees the same prompt each time, but the codebase has changed from previous iterations. This creates a powerful feedback loop where the agent iteratively improves its work until all tests pass.

Multi-Agent Flexibility

Switch between AI coding agents without changing your workflow:

• Claude Code (--agent claude-code) — Anthropic's powerful coding agent
• Codex (--agent codex) — OpenAI's code-specialized model
• Copilot CLI (--agent copilot) — GitHub's agentic coding tool
• OpenCode (--agent opencode) — Open-source default option

Key Features

• Multi-Agent Support — Use Claude Code, Codex, or OpenCode with the same workflow
• Self-Correcting Loops — Agent sees its previous work and fixes its own mistakes
• Autonomous Execution — Set it running and come back to finished code
• Task Tracking — Built-in task management with --tasks mode
• Live Monitoring — Check progress with --status from another terminal
• Mid-Loop Hints — Inject guidance with --add-context without stopping

Why Use an Agentic Loop?

| Benefit | How it works | |---------|--------------| | Self-Correction | AI sees test failures from previous runs, fixes them | | Persistence | Walk away, come back to completed work | | Iteration | Complex tasks broken into incremental progress | | Automation | No babysitting—loop handles retries | | Observability | Monitor progress with --status, see history and struggle indicators | | Mid-Loop Guidance | Inject hints with --add-context without stopping the loop |

Installation

Prerequisites:

• Bun runtime
• At least one AI coding agent CLI:
  • Claude Code — Anthropic's Claude Code CLI
  • Codex — OpenAI's Codex CLI
  • Copilot CLI — GitHub's Copilot CLI
  • OpenCode — Open-source AI coding assistant

npm (recommended)

npm install -g @th0rgal/ralph-wiggum

Bun

bun add -g @th0rgal/ralph-wiggum

From source

git clone https://github.com/Th0rgal/open-ralph-wiggum
cd open-ralph-wiggum
./install.sh

git clone https://github.com/Th0rgal/open-ralph-wiggum
cd open-ralph-wiggum
.\install.ps1

This installs the ralph CLI command globally.

Quick Start

# Simple task with iteration limit
ralph "Create a hello.txt file with 'Hello World'. Output <promise>DONE</promise> when complete." \
  --max-iterations 5

# Build something real
ralph "Build a REST API for todos with CRUD operations and tests. \
  Run tests after each change. Output <promise>COMPLETE</promise> when all tests pass." \
  --max-iterations 20

# Use Claude Code instead of OpenCode
ralph "Create a small CLI and document usage. Output <promise>COMPLETE</promise> when done." \
  --agent claude-code --model claude-sonnet-4 --max-iterations 5

# Use Codex instead of OpenCode
ralph "Create a small CLI and document usage. Output <promise>COMPLETE</promise> when done." \
  --agent codex --model gpt-5-codex --max-iterations 5

# Use Copilot CLI
ralph "Create a small CLI and document usage. Output <promise>COMPLETE</promise> when done." \
  --agent copilot --max-iterations 5

# Complex project with Tasks Mode
ralph "Build a full-stack web application with user auth and database" \
  --tasks --max-iterations 50

Environment Variables

Configure agent binaries with these environment variables:

| Variable | Description | Default | |----------|-------------|---------| | RALPH_OPENCODE_BINARY | Path to OpenCode CLI | "opencode" | | RALPH_CLAUDE_BINARY | Path to Claude Code CLI | "claude" | | RALPH_CODEX_BINARY | Path to Codex CLI | "codex" | | RALPH_COPILOT_BINARY | Path to Copilot CLI | "copilot" |

Note for Windows users: Ralph automatically resolves .cmd extensions for npm-installed CLIs. If you encounter "command not found" errors, you can use these environment variables to specify the full path to the executable.

Commands

Running a Loop

ralph "<prompt>" [options]

Options:
  --agent AGENT            AI agent to use: opencode (default), claude-code, codex, copilot
  --min-iterations N       Minimum iterations before completion allowed (default: 1)
  --max-iterations N       Stop after N iterations (default: unlimited)
  --completion-promise T   Text that signals completion (default: COMPLETE)
  --abort-promise TEXT     Phrase that signals early abort (e.g., precondition failed)
  --tasks, -t              Enable Tasks Mode for structured task tracking
  --task-promise T         Text that signals task completion (default: READY_FOR_NEXT_TASK)
  --model MODEL            Model to use (agent-specific)
  --rotation LIST          Agent/model rotation for each iteration (comma-separated)
  --prompt-file, --file, -f  Read prompt content from a file
  --prompt-template PATH   Use custom prompt template (see Custom Prompts)
  --no-stream              Buffer agent output and print at the end
  --verbose-tools          Print every tool line (disable compact tool summary)
  --no-plugins             Disable non-auth OpenCode plugins for this run (opencode only)
  --no-commit              Don't auto-commit after iterations
  --allow-all              Auto-approve all tool permissions (default: on)
  --no-allow-all           Require interactive permission prompts
  --help                   Show help

Tasks Mode

Tasks Mode allows you to break complex projects into smaller, manageable tasks. Ralph works on one task at a time and tracks progress in a markdown file.

# Enable Tasks Mode
ralph "Build a complete web application" --tasks --max-iterations 20

# Custom task completion signal
ralph "Multi-feature project" --tasks --task-promise "TASK_DONE"

Task Management Commands

# List current tasks
ralph --list-tasks

# Add a new task
ralph --add-task "Implement user authentication"

# Remove task by index
ralph --remove-task 3

# Show status (tasks shown automatically when tasks mode is active)
ralph --status

How Tasks Mode Works

1. Task File: Tasks are stored in .ralph/ralph-tasks.md
2. One Task Per Iteration: Ralph focuses on a single task to reduce confusion
3. Automatic Progression: When a task completes (<promise>READY_FOR_NEXT_TASK</promise>), Ralph moves to the next
4. Persistent State: Tasks survive loop restarts
5. Focused Context: Smaller contexts per iteration reduce costs and improve reliability

Task status indicators:

• [ ] - Not started
• [/] - In progress
• [x] - Complete

Example task file:

# Ralph Tasks

- [ ] Set up project structure
- [x] Initialize git repository
- [/] Implement user authentication
  - [ ] Create login page
  - [ ] Add JWT handling
- [ ] Build dashboard UI

Custom Prompt Templates

You can fully customize the prompt sent to the agent using --prompt-template. This is useful for integrating with custom workflows or tools.

ralph "Build a REST API" --prompt-template ./my-template.md

Available variables:

| Variable | Description | |----------|-------------| | {{iteration}} | Current iteration number | | {{max_iterations}} | Maximum iterations (or "unlimited") | | {{min_iterations}} | Minimum iterations | | {{prompt}} | The user's task prompt | | {{completion_promise}} | Completion promise text (e.g., "COMPLETE") | | {{abort_promise}} | Abort promise text (if configured) | | {{task_promise}} | Task promise text (for tasks mode) | | {{context}} | Additional context added mid-loop | | {{tasks}} | Task list content (for tasks mode) |

Example template (my-template.md):

# Iteration {{iteration}} / {{max_iterations}}

## Task
{{prompt}}

## Instructions
1. Check beads for current status
2. Decide what to do next
3. When the epic in beads is complete, output:
   <promise>{{completion_promise}}</promise>

{{context}}

Monitoring & Control

# Check status of active loop (run from another terminal)
ralph --status

# Add context/hints for the next iteration
ralph --add-context "Focus on fixing the auth module first"

# Clear pending context
ralph --clear-context

Status Dashboard

The --status command shows:

• Active loop info: Current iteration, elapsed time, prompt
• Pending context: Any hints queued for next iteration
• Current tasks: Automatically shown when tasks mode is active (or use --tasks)
• Iteration history: Last 5 iterations with tools used, duration
• Struggle indicators: Warnings if agent is stuck (no progress, repeated errors)

╔══════════════════════════════════════════════════════════════════╗
║                    Ralph Wiggum Status                           ║
╚══════════════════════════════════════════════════════════════════╝

🔄 ACTIVE LOOP
   Iteration:    3 / 10
   Elapsed:      5m 23s
   Promise:      COMPLETE
   Prompt:       Build a REST API...

📊 HISTORY (3 iterations)
   Total time:   5m 23s

   Recent iterations:
   🔄 #1: 2m 10s | Bash:5 Write:3 Read:2
   🔄 #2: 1m 45s | Edit:4 Bash:3 Read:2
   🔄 #3: 1m 28s | Bash:2 Edit:1

⚠️  STRUGGLE INDICATORS:
   - No file changes in 3 iterations
   💡 Consider using: ralph --add-context "your hint here"

Mid-Loop Context Injection

Guide a struggling agent without stopping the loop:

# In another terminal while loop is running
ralph --add-context "The bug is in utils/parser.ts line 42"
ralph --add-context "Try using the singleton pattern for config"

Context is automatically consumed after one iteration.

Troubleshooting

Plugin errors

This package is CLI-only. If OpenCode tries to load a ralph-wiggum or open-ralph-wiggum plugin, remove it from your OpenCode plugin list (opencode.json), or run:

ralph "Your task" --no-plugins

ProviderModelNotFoundError / Model not configured

If you see ProviderModelNotFoundError or "Provider returned error", you need to configure a default model:

For OpenCode:

1. Edit ~/.config/opencode/opencode.json:

   {
     "$schema": "https://opencode.ai/config.json",
     "model": "your-provider/model-name"
   }

2. Or use the --model flag: ralph "task" --model provider/model

For other agents: Use the --model flag to specify the model explicitly.

"command not found" on Windows

Ralph automatically tries .cmd extensions on Windows. If you still have issues:

1. Set the full path using environment variables:

   $env:RALPH_OPENCODE_BINARY = "C:\path\to\opencode.cmd"

2. Or add the CLI to your PATH

"bun: command not found"

Install Bun: https://bun.sh

Writing Good Prompts

Include Clear Success Criteria

❌ Bad:

Build a todo API

✅ Good:

Build a REST API for todos with:
- CRUD endpoints (GET, POST, PUT, DELETE)
- Input validation
- Tests for each endpoint

Run tests after changes. Output <promise>COMPLETE</promise> when all tests pass.

Use Verifiable Conditions

❌ Bad:

Make the code better

✅ Good:

Refactor auth.ts to:
1. Extract validation into separate functions
2. Add error handling for network failures
3. Ensure all existing tests still pass

Output <promise>DONE</promise> when refactored and tests pass.

Always Set Max Iterations

# Safety net for runaway loops
ralph "Your task" --max-iterations 20

Recommended PRD Format

Ralph treats prompt files as plain text, so any format works. For best results, use a concise PRD with:

• Goal: one sentence summary of the desired outcome
• Scope: what is in/out
• Requirements: numbered, testable items
• Constraints: tech stack, performance, security, compatibility
• Acceptance criteria: explicit success checks
• Completion promise: include <promise>COMPLETE</promise> (or match your --completion-promise)

Example (Markdown):

# PRD: Add Export Button

## Goal
Let users export reports as CSV from the dashboard.

## Scope
- In: export current report view
- Out: background exports, scheduling

## Requirements
1. Add "Export CSV" button to dashboard header.
2. CSV includes columns: date, revenue, sessions.
3. Works for reports up to 10k rows.

## Constraints
- Keep current UI styling.
- Use existing CSV utility in utils/csv.ts.

## Acceptance Criteria
- Clicking button downloads a valid CSV.
- CSV opens cleanly in Excel/Sheets.
- All existing tests pass.

## Completion Promise
<promise>COMPLETE</promise>

JSON Feature List (Recommended for Complex Projects)

For larger projects, a structured JSON feature list works better than prose. Based on Anthropic's research on effective agent harnesses, JSON format reduces the chance of agents inappropriately modifying test definitions.

Create a features.json file:

{
  "features": [
    {
      "category": "functional",
      "description": "Export button downloads CSV with current report data",
      "steps": [
        "Navigate to dashboard",
        "Click 'Export CSV' button",
        "Verify CSV file downloads",
        "Open CSV and verify columns: date, revenue, sessions",
        "Verify data matches displayed report"
      ],
      "passes": false
    },
    {
      "category": "functional",
      "description": "Export handles large reports up to 10k rows",
      "steps": [
        "Load report with 10,000 rows",
        "Click 'Export CSV' button",
        "Verify export completes without timeout",
        "Verify all rows present in CSV"
      ],
      "passes": false
    },
    {
      "category": "ui",
      "description": "Export button matches existing dashboard styling",
      "steps": [
        "Navigate to dashboard",
        "Verify button uses existing button component",
        "Verify button placement in header area"
      ],
      "passes": false
    }
  ]
}

Then reference it in your prompt:

Read features.json for the feature list. Work through each feature one at a time.
After verifying a feature works end-to-end, update its "passes" field to true.
Do NOT modify the description or steps - only change the passes boolean.
Output <promise>COMPLETE</promise> when all features pass.

Why JSON? Agents are less likely to inappropriately modify JSON test definitions compared to Markdown. The structured format keeps agents focused on implementation rather than redefining success criteria.

When to Use Ralph

Good for:

• Tasks with automatic verification (tests, linters, type checking)
• Well-defined tasks with clear completion criteria
• Greenfield projects where you can walk away
• Iterative refinement (getting tests to pass)

Not good for:

• Tasks requiring human judgment
• One-shot operations
• Unclear success criteria
• Production debugging

How It Works

┌─────────────────────────────────────────────────────────────┐
│                                                             │
│   ┌──────────┐    same prompt    ┌──────────┐              │
│   │          │ ───────────────▶  │          │              │
│   │  ralph   │                   │ AI Agent │              │
│   │   CLI    │ ◀─────────────── │          │              │
│   │          │   output + files  │          │              │
│   └──────────┘                   └──────────┘              │
│        │                              │                     │
│        │ check for                    │ modify              │
│        │ <promise>                    │ files               │
│        ▼                              ▼                     │
│   ┌──────────┐                   ┌──────────┐              │
│   │ Complete │                   │   Git    │              │
│   │   or     │                   │  Repo    │              │
│   │  Retry   │                   │ (state)  │              │
│   └──────────┘                   └──────────┘              │
│                                                             │
└─────────────────────────────────────────────────────────────┘

1. Ralph sends your prompt to the selected agent
2. The agent works on the task, modifies files
3. Ralph checks output for completion promise
4. If not found, repeat with same prompt
5. AI sees previous work in files
6. Loop until success or max iterations

Project Structure

ralph-wiggum/
├── bin/ralph.js                  # CLI entrypoint (npm wrapper)
├── ralph.ts                      # Main loop implementation
├── package.json                  # Package config
├── install.sh / install.ps1     # Installation scripts
└── uninstall.sh / uninstall.ps1 # Uninstallation scripts

State Files (in .ralph/)

During operation, Ralph stores state in .ralph/:

• ralph-loop.state.json - Active loop state
• ralph-history.json - Iteration history and metrics
• ralph-context.md - Pending context for next iteration
• ralph-tasks.md - Task list for Tasks Mode (created when --tasks is used)

Uninstall

npm uninstall -g @th0rgal/ralph-wiggum

npm uninstall -g @th0rgal/ralph-wiggum

Agent-Specific Notes

Claude Code

Claude Code is Anthropic's official CLI for Claude. Use it with Open Ralph Wiggum for powerful autonomous coding:

ralph "Refactor the auth module and ensure tests pass" \
  --agent claude-code \
  --model claude-sonnet-4 \
  --max-iterations 15

OpenAI Codex

Codex is OpenAI's code-specialized agent. Perfect for code generation and refactoring tasks:

ralph "Generate unit tests for all utility functions" \
  --agent codex \
  --model gpt-5-codex \
  --max-iterations 10

OpenCode

OpenCode is an open-source AI coding assistant. It's the default agent:

ralph "Fix all TypeScript errors" --max-iterations 10

Copilot CLI

Copilot CLI is GitHub's agentic coding tool (public preview). It requires a GitHub Copilot subscription and authentication via GH_TOKEN, GITHUB_TOKEN, or prior copilot /login.

Install:

npm install -g @github/copilot
# or
brew install copilot-cli

Usage:

ralph "Refactor the auth module and add tests" \
  --agent copilot \
  --max-iterations 15

# With a specific model
ralph "Build a REST API" \
  --agent copilot \
  --model claude-opus-4.6 \
  --max-iterations 10

Notes:

• Default model is Claude Sonnet 4.5; override with --model
• --allow-all (default) maps to --allow-all + --no-ask-user in Copilot CLI
• --no-plugins has no effect with Copilot CLI
• Authentication: set GH_TOKEN / GITHUB_TOKEN env var, or run copilot /login first

Agent Rotation

Agent rotation lets you cycle through different agent/model combinations across iterations. This is useful for leveraging the strengths of different models or comparing their performance on a task.

Format

Each rotation entry uses the agent:model format:

--rotation "agent1:model1,agent2:model2,agent3:model3"

Valid agents: opencode, claude-code, codex, copilot

Example Usage

# Alternate between OpenCode and Claude Code
ralph "Build a REST API" \
  --rotation "opencode:claude-sonnet-4,claude-code:claude-sonnet-4" \
  --max-iterations 10

# Cycle through three different configurations
ralph "Refactor the auth module" \
  --rotation "opencode:claude-sonnet-4,claude-code:claude-sonnet-4,codex:gpt-5-codex" \
  --max-iterations 15

# Include Copilot in the rotation
ralph "Build a REST API" \
  --rotation "opencode:claude-sonnet-4,copilot:claude-sonnet-4" \
  --max-iterations 10

Flag Interaction

When --rotation is used, the --agent and --model flags are ignored. The rotation list takes precedence for agent/model selection.

Cycling Behavior

The rotation cycles back to the first entry after reaching the end:

• Iteration 1 → Entry 1
• Iteration 2 → Entry 2
• Iteration 3 → Entry 1 (wraps around for a 2-entry rotation)
• ...and so on

Error Messages

Invalid rotation entries produce clear error messages:

Invalid agent name:

Error: Invalid agent 'invalid' in rotation entry 'invalid:model'. Valid agents: opencode, claude-code, codex, copilot

Malformed entry (missing colon):

Error: Invalid rotation entry 'opencode-model'. Expected format: agent:model

Empty values:

Error: Invalid rotation entry 'opencode:'. Both agent and model are required.

Status Display

When using --status with an active rotation, the output shows all rotation entries and marks the current one:

🔄 ACTIVE LOOP
   Iteration:    3 / 10
   Prompt:       Build a REST API...

   Rotation (position 1/2):
   1. opencode:claude-sonnet-4  **ACTIVE**
   2. claude-code:claude-sonnet-4

Iteration History

The --status command shows which agent and model was used for each iteration:

📊 HISTORY (3 iterations)
   Total time:   5m 23s

   Recent iterations:
   #1  2m 10s  opencode / claude-sonnet-4  Bash(5) Write(3) Read(2)
   #2  1m 45s  claude-code / claude-sonnet-4  Edit(4) Bash(3) Read(2)
   #3  1m 28s  opencode / claude-sonnet-4  Bash(2) Edit(1)

Learn More

• Original Ralph Wiggum technique by Geoffrey Huntley
• Ralph Orchestrator

See Also

Check out 🏝️ sandboxed.sh — a dashboard for orchestrating AI agents with workspace management, real-time monitoring, and multi-agent workflows.

License

MIT