ralphkit 0.1.1rc4

Iterative work/review loop for Claude Code

ralphkit

A step-based pipeline for Claude Code. Define setup, loop, and cleanup phases in a YAML config. The loop iterates until the reviewer says SHIP or max iterations are reached.

Inspired by the ralph loop.

Install

pip install ralphkit

With uv:

uv tool install ralphkit

Or run directly without installing:

uvx ralphkit ralph-loop "your task here" --config ralph.yaml

Quick Start

ralph-loop "Create a Python function in prime.py that checks if a number is prime. Include unit tests." --config configs/example.yaml

Usage

ralph-loop TASK --config PATH [OPTIONS]

Arguments:

Argument	Description	Default
TASK	Task description (string or path to .md file)	required
--config PATH	Path to YAML config file	required
--max-iterations N	Override max iterations from config	from config
-f / --force	Skip confirmation prompt	off

Examples:

# Inline task
ralph-loop "Build a REST API" --config ralph.yaml

# Task from a markdown file
ralph-loop task.md --config ralph.yaml

# Override max iterations
ralph-loop "Build a REST API" --config ralph.yaml --max-iterations 5

# Skip confirmation
ralph-loop "Build a REST API" --config ralph.yaml -f

Config file

A YAML config file is required. It defines three phases — setup, loop, and cleanup — each containing a list of steps. Only loop is required.

max_iterations: 10
default_model: opus

# Optional: runs once before the loop
setup:
  - step_name: init
    task_prompt: "Initialize the project."
    system_prompt: "You are a setup agent."

# Required: iterated until SHIP or max iterations
loop:
  - step_name: worker
    task_prompt: "Read .ralphkit/task.md and begin working. This is iteration {iteration}."
    system_prompt: "You are a worker in a RALPH LOOP..."
    model: opus
  - step_name: reviewer
    task_prompt: "Review the work done for the task in .ralphkit/task.md."
    system_prompt: "You are a code reviewer..."
    model: sonnet

# Optional: runs once after the loop (always, even on failure)
cleanup:
  - step_name: finalize
    task_prompt: "Clean up temporary files."
    system_prompt: "You are a cleanup agent."

Required top-level keys: max_iterations, default_model, loop

Each step requires step_name, task_prompt, and system_prompt. The optional model field overrides default_model for that step.

Template variables

Both task_prompt and system_prompt support template variables via {variable_name}. Unrecognized variables are left as-is.

All phases:

Variable	Description
{step_name}	Current step's name
{max_iterations}	Configured max iterations
{default_model}	Pipeline's default model
{model}	Resolved model for this step
{state_dir}	State directory path (.ralphkit)

Loop phase only:

Variable	Description
{iteration}	Current iteration number (1-based)

See configs/example.yaml for a complete working config.

How It Works

 Setup (once)          Loop (iterate)              Cleanup (once, always)
┌──────────┐    ┌───────────────────────┐    ┌──────────────┐
│ step 1   │    │ step 1 (e.g. worker)  │    │ step 1       │
│ step 2   │    │ step 2 (e.g. reviewer)│    │ ...          │
│ ...      │    │ ...                   │    └──────────────┘
└──────────┘    │ SHIP? → done          │
                │ REVISE? → loop again  │
                └───────────────────────┘

Each loop iteration runs all loop steps in order, then checks the review result:

1. Loop steps — each step runs claude with its configured prompts and model.
2. After all steps, the verdict is read from .ralphkit/review-result.md.
3. SHIP → exit successfully. REVISE → feedback is preserved for the next iteration.

The cleanup phase always runs (even if the loop exits with an error), similar to a finally block.

State Files

State is persisted in .ralphkit/ in the current working directory so each stateless claude -p invocation can pick up where the last left off.

File	Purpose
task.md	The task description
iteration.md	Current iteration number
work-summary.md	What the worker did this iteration
work-complete.md	Created when the worker thinks it's done
review-result.md	SHIP or REVISE
review-feedback.md	Specific feedback from the reviewer
RALPH-BLOCKED.md	Created by a step if it cannot proceed

Requirements

• Claude Code CLI (claude must be on your PATH)
• Python 3.10+