About Ralph Wiggum Loop
Ralph Wiggum Loop is a cross-platform iterative development agent plugin for teams using spec-driven development. A worker model implements a task while a separate reviewer model evaluates it through SHIP/REVISE cycles.
Key features
- 01Worker/reviewer development loop
- 02SHIP/REVISE review decisions
- 03Spec-driven development skills
- 04Bash and PowerShell implementations
- 05CLI, stdio, and HTTP modes
Use cases
- 01Iterating on an implementation against a specification
- 02Reviewing changes with a separate model
- 03Running the workflow on Linux, macOS, or Windows
MCP support
It runs as an MCP server over stdio or streamable HTTP, exposing the iterative development workflow to MCP clients.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEralph-wiggum-loop
Multi-model iterative development agent plugin — Ralph Loop with cross-model worker/reviewer architecture, spec-driven development skills, Stop hooks, and SHIP/REVISE decision engine.
Overview
The Ralph Loop implements a two-phase iterative workflow where a worker model does the work and a reviewer model provides cross-model review, iterating until the reviewer says "SHIP".
This project is a cross-platform Agent Plugin (plugin.json, mcp.json, .agents/skills/ralph-wiggum-loop/ & skills/ralph-wiggum-loop/) with native implementations for:
- Linux / macOS (Bash):
bin/ralph-wiggum-loop.sh(usingbin/mcp-sdk.sh) - Windows (PowerShell):
bin/ralph-wiggum-loop.ps1(usingbin/mcp-sdk.psm1) - Polyglot Runner:
bin/script-runner.sh/bin/script-runner.ps1(runs in both POSIXsh/bashand PowerShell)
Install Skill (.agents/skills/)
Per the Agent Skills Specification, install the skill to .agents/skills/:
# Project-level (.agents/skills/ralph-wiggum-loop) or User-level (~/.agents/skills/ralph-wiggum-loop)
mkdir -p .agents/skills
cp -R skills/ralph-wiggum-loop .agents/skills/ralph-wiggum-loop
New-Item -ItemType Directory -Path .agents/skills -Force | Out-Null
Copy-Item -Recurse -Force skills/ralph-wiggum-loop .agents/skills/ralph-wiggum-loop
OS-Specific MCP Servers (mcp.json)
| MCP Server Name | OS / Runtime | Transport | Command / Endpoint |
|---|---|---|---|
ralph-wiggum-loop | Linux / macOS (Bash) | stdio | ./bin/script-runner.sh ralph-wiggum-loop --stdio |
ralph-wiggum-loop-pwsh | Windows (PowerShell 7+) | stdio | pwsh -NoProfile -ExecutionPolicy Bypass -File ${PLUGIN_ROOT}/bin/script-runner.ps1 ralph-wiggum-loop --stdio |
ralph-wiggum-loop-powershell | Windows (PowerShell 5.1) | stdio | powershell.exe -NoProfile -ExecutionPolicy Bypass -File ${PLUGIN_ROOT}/bin/script-runner.ps1 ralph-wiggum-loop --stdio |
ralph-wiggum-loop-http | Cross-Platform | streamable-http | http://127.0.0.1:8080/mcp |
Quick Start
1. CLI Mode
- Linux / macOS (Bash):
./bin/ralph-wiggum-loop.sh "Implement user authentication with JWT tokens" --profile pro - Windows (PowerShell):
pwsh -NoProfile -ExecutionPolicy Bypass -File .\bin\ralph-wiggum-loop.ps1 "Implement user authentication with JWT tokens" --profile pro
2. MCP Server (stdio Mode)
- Linux / macOS (Bash):
./bin/ralph-wiggum-loop.sh --stdio - Windows (PowerShell):
pwsh -NoProfile -ExecutionPolicy Bypass -File .\bin\ralph-wiggum-loop.ps1 --stdio
3. MCP Server (streamable-http Service Mode)
- Linux / macOS (Bash):
./bin/script-runner.sh start-http-server start --host 127.0.0.1 --port 8080 - Windows (PowerShell):
pwsh -NoProfile -ExecutionPolicy Bypass -File .\bin\script-runner.ps1 start-http-server start --host 127.0.0.1 --port 8080
Documentation
- Skill & Agent Instructions — OS selection rules, loop execution modes, and Streamable HTTP setup
- Full Documentation — API reference, tools, state management
- Deployment Guide — Install and configure
Repository
- Source: https://github.com/sheldonrobinson/ralph-wiggum-loop
- Agent Plugin Spec: https://agent-plugins.org
- MCP Spec: https://modelcontextprotocol.io
License
MIT
Comments
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