leanlab 0.2.3

A self-improving lab for AI agents — evolve ML experiments against a frozen metric, or ship coding tasks through a spec → gate → review → merge loop with locked acceptance tests.

leanlab

Self-improving labs for AI agents. Point leanlab at a task and a team of Claude agents iterates toward a goal — evolving ML / optimization experiments against a frozen metric, or shipping coding tasks through a spec → gate → review → merge loop with locked acceptance tests.

Install

pipx install leanlab        # or:  pip install leanlab   ·   uvx leanlab

📦 On PyPI: pypi.org/project/leanlab

Requires Python 3.11+ and the claude CLI (the agents run on Claude Code).

Quick start

leanlab runs inside your own project — each lab lives in a .leanlab/<name>/ folder; the engine stays in the installed tool.

Metric lab — evolve a number (ML, optimization, anything that prints a score):

cd ~/my-project
leanlab init iris          # describe the task; Claude drafts the lab + scorer
leanlab check iris         # verify it's wired correctly (free)
leanlab lock iris          # freeze the scorer
leanlab run iris --n 5     # the agents evolve experiments (uses Claude)
leanlab serve iris         # watch the live dashboard

Coding lab — ship a coding task with locked acceptance tests:

cd ~/my-repo                              # a git repository
leanlab spec "add a /health endpoint"    # spec-writer drafts + locks the tests
leanlab build add-health                 # engineer → gate → reviewer → merge
leanlab board                            # live board: tasks, timeline, playbook

Let Claude Code drive it

cd ~/my-project && leanlab init --for-agent   # installs a Claude Code skill

Then just ask Claude Code — "use leanlab to add a /health endpoint" — and it specs, builds, and merges through the honest test gate for you.

Docs

• docs/USAGE.md — every command, in order, with examples.
• docs/OVERVIEW.md — how it works: the loop, the two lab types, the coding-lab flow, and the project structure.
• CONTRIBUTING.md — local development (uv, tests, the React board).

MIT licensed — see LICENSE.