deepagent/deepagents_sourcecode/examples/ralph_mode

Ralph Mode for DeepAgents

What is Ralph?

Ralph is an autonomous looping pattern created by Geoff Huntley that went viral in late 2025. The original implementation is literally one line:

while :; do cat PROMPT.md | agent ; done

Each loop starts with fresh context—the simplest pattern for context management. No conversation history to manage, no token limits to worry about. Just start fresh every iteration.

The filesystem and git allow the agent to track progress over time. This serves as its memory and worklog.

Quick Start

# Install uv (if you don't have it)
curl -LsSf https://astral.sh/uv/install.sh | sh

# Create a virtual environment
uv venv
source .venv/bin/activate

# Install the CLI
uv pip install deepagents-cli

# Download the script (or copy from examples/ralph_mode/ if you have the repo)
curl -O https://raw.githubusercontent.com/langchain-ai/deepagents/master/examples/ralph_mode/ralph_mode.py

# Run Ralph
python ralph_mode.py "Build a Python programming course for beginners. Use git."

Usage

# Unlimited iterations (Ctrl+C to stop)
python ralph_mode.py "Build a Python course"

# With iteration limit
python ralph_mode.py "Build a REST API" --iterations 5

# With specific model
python ralph_mode.py "Create a CLI tool" --model claude-haiku-4-5-20251001

How It Works

1. You provide a task — declarative, what you want (not how)
2. Agent runs — creates files, makes progress
3. Loop repeats — same prompt, but files persist
4. You stop it — Ctrl+C when satisfied

Credits

• Original Ralph concept by Geoff Huntley
• Brief History of Ralph by HumanLayer