PRD-driven loop
Generate a PRD and task list from raw requirements so the loop has a durable source of truth instead of a single prompt.
Ralph Loop
_____ _ _____ _ _
| __ \ /\ | | | __ \| | | |
| |__) | / \ | | | |__) | |__| |
| _ / / /\ \ | | | ___/| __ |
| | \ \ / ____ \| |____| | | | | |
|_| \_\/_/ \_\______|_| |_| |_|
A long-running AI agent loop that can code for days.
Ralph iterates through a task list, runs your favorite agentic CLI in Docker Sandboxes, and keeps working until the job is done.
$ npx @pageai/ralph-loop█
agent-loop.exe
// live-ish terminal playback
Point it at a task list. Let it loop.
ralph loop sessionpid: long-running
$ sbx run --name ralph-loop claude .
ralph: docker sandbox online
[001] task: create PRD + task list ✓
[002] task: implement feature slice ✓
[003] task: run tests and typecheck ✓
ralph: loop complete, ready for review █
// start here
Watch the walkthrough
▶ ralph wiggum loop demo
// features
Built for unattended agent work
Ralph is a hackable, long-running loop. Point it at a task list, walk away, and come back to a stack of commits.
Task lookup table
Per-task specs with detailed steps. Scales to hundreds of tasks without losing context between iterations.
Docker Sandboxes per agent
Deterministic ralph-<agent>-<dir>-<hash> sandboxes. Isolated, reusable, and stopped cleanly on exit.
Multi-agent ready
Claude, Codex, Cursor, Copilot, Gemini, opencode out of the box. Pass agent flags through the same script.
Live observability
Step detection, stream preview, screenshot capture, full history logs, and per-iteration timing while it runs.
Steerable mid-flight
Edit .agent/STEERING.md while the loop is running. Ralph reads it each iteration and prioritizes critical work.