automation

Leon

Name: Leon
Author: leon-ai

Leon is your open-source personal assistant.

17,501 stars1,470 forksTypeScriptUpdated 9/10/2026100% free · open source

What it does

Leon is an open‑source, self‑hosted AI assistant you can talk to via the web UI or CLI.

When to use it

•You need a privacy‑first personal assistant that runs on your own server.
•You want to add custom “skills” (e.g., fetch stock prices, send Slack messages) without vendor lock‑in.
•You prefer a free alternative to ChatGPT that you can extend with TypeScript code.

Ready-to-paste prompt

In the web UI, type: **"Create a Trello card for our next sprint with the title ‘User onboarding flow’ and assign it to @alice"** – Leon will call the Trello API (once you configure the Trello skill) and confirm the card creation.

Heads up: Leon won’t work until you provide a valid LLM API key (OpenAI, Anthropic, etc.) in the .env file; missing or wrong keys cause the server to start but all assistant requests fail with 401 errors.

Saves to your device

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

🛠️ Technical setup

Expect 20–40 minutes in a terminal — or let your AI agent drive it.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283 && curl -fsSL https://workflowstacks.com/api/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283/claude-skill -o ~/.claude/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

How Leon works

Codeflow

Free to inspect

Leon is a very large TypeScript project (~105k lines across 832 code files, plus 38 test files). It is a full software project: use it through its install path rather than reading it end to end. Last commit this month, MIT license, has a test suite.

Size

Very large codebase

~105k lines · 832 code files · days to read — use, don't read

Setup

Developer setup

A real software project. Use it via its install path; don't expect to read it all.

Runs on

Node.js

Needs API keys (.env)

TypeScript 72%Python 15%JavaScript 9%Sass 3%SCSS 1%

Where to start reading

1
README.md
Start here — what it does and how to install it
2
AGENTS.md
The instructions the AI actually follows
3
package.json
Dependencies and the commands it exposes
4
.env.sample
The API keys and settings you must provide
5
skills/agent/live-tutorial/SKILL.md
Inside skills/ — an example of what the AI is told to do

What's in each folder

skills/Prompts, skills & agent definitions247 files

app/Core code — the actual logic42 files

core/Core code — the actual logic22 files

server/Backend / API243 files

bin/Command-line entry points11 files

tools/Helper scripts232 files

web-app/Folder148 files

aurora/Folder116 files

READMEHas testsDocumentedCI checksMIT licenseUpdated this month

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

🛠️ Technical setup

Expect 20–40 minutes in a terminal — or let your AI agent drive it.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283 && curl -fsSL https://workflowstacks.com/api/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283/claude-skill -o ~/.claude/skills/e7392fc5-7a5c-4a24-a871-98e918c3f283/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

Quick Actions

Details

Creator

leon-ai

Language

TypeScript

Do this with a working workflow

Pages we wrote and tested that put a skill like this to work — importable n8n templates, outcome guides and Claude Desktop configs.

Free n8n template

AI Support Agent (Chat)

A chat agent that answers customer questions from YOUR business info — with conversation memory. It never invents policies; anything it doesn't know, it hands to a human.