# learn.ninja

> Give your AI agent an article, notes, docs, a transcript, or code. It writes one short, interactive lesson and gives you a link to share. Free, no account.

learn.ninja is a skill for AI agents. The agent turns what the user gives it (a topic, an article, notes, docs, a transcript, or code) into one short, interactive lesson in a JSON format, checks it, and publishes it to a link like https://learn.ninja/l/how-compound-interest-works-k3x9a2mq. Learners play it in the browser: short screens called bricks, with feedback on every answer.

## When to use it

- The user asks to make, generate, or publish a lesson, quiz, tutorial, or interactive explainer.
- The user wants to learn, or teach someone, a concept from something they're reading.

## Install

```bash
npx skills add https://learn.ninja -g
```

Then read the skill's SKILL.md and follow it: write the lesson, run `validate` until it passes, then `publish`, and give the user the link. Lessons are free, need no account, and last 24 hours.

## Docs

- [Introduction](https://learn.ninja/docs.md): learn.ninja turns anything you give your agent into one short, interactive lesson you can share as a link.
- [Install the skill](https://learn.ninja/docs/install.md): Add the learn.ninja skill to Claude Code, Codex, Cursor, or any agent that supports skills.
- [Quick start](https://learn.ninja/docs/quick-start.md): Make, play, change, and share your first lesson in a few minutes.
- [Blank](https://learn.ninja/docs/bricks/blank.md): Fill the gaps in a sentence, formula, or code with word chips.
- [Choice](https://learn.ninja/docs/bricks/choice.md): Pick one answer, or every answer that applies.
- [Compare](https://learn.ninja/docs/bricks/compare.md): Two options side by side; pick the better one.
- [Concept](https://learn.ninja/docs/bricks/concept.md): Teaches one idea in a few sentences, often with a visual, a formula, or code.
- [Hotspot](https://learn.ninja/docs/bricks/hotspot.md): Tap the right spot in a visual or a line of code.
- [Overview](https://learn.ninja/docs/bricks.md): A lesson is made of bricks, one per screen. Here's every kind and when your agent uses it.
- [Match](https://learn.ninja/docs/bricks/match.md): Link each item on the left to its partner on the right.
- [Order](https://learn.ninja/docs/bricks/order.md): Put items in the right order.
- [Scenario](https://learn.ninja/docs/bricks/scenario.md): A realistic situation; choose what you'd do.
- [Sort](https://learn.ninja/docs/bricks/sort.md): Drag each item into the group it belongs to.
- [How lessons work](https://learn.ninja/docs/lessons/how-lessons-work.md): What's in a lesson, the order it plays in, and how answers are scored.
- [Lesson format](https://learn.ninja/docs/lessons/lesson-format.md): Every field of a lesson file (spec 0.3), with short examples. The same reference the skill reads.
- [Links and editing](https://learn.ninja/docs/lessons/sharing.md): How lesson links work, how long they last, who can see them, and how to change a lesson.
- [For agents](https://learn.ninja/docs/reference/agents.md): Machine-readable versions of this site, for AI agents and tools.
- [Publish API](https://learn.ninja/docs/reference/api.md): The HTTP API behind publishing. The CLI uses it; you can too.
- [CLI](https://learn.ninja/docs/reference/cli.md): The learn command the skill uses to check and publish lessons.
- [JSON Schema](https://learn.ninja/docs/reference/json-schema.md): The formal definition of a lesson file, for editors, validators, and your own tools.
- [Overview](https://learn.ninja/docs/skills.md): How the learn.ninja skill is built. A core every lesson uses, plus topic packs with extra guidance for particular subjects.
- [Languages](https://learn.ninja/docs/skills/languages.md): The topic pack for teaching a foreign language. Your agent reads it for vocabulary, phrase, and grammar lessons.
- [Math](https://learn.ninja/docs/skills/math.md): The topic pack for arithmetic, percentages, algebra, probability, and money math. Your agent reads it for lessons with numbers and formulas.
- [Write a pack](https://learn.ninja/docs/skills/write-a-pack.md): Add a topic pack for a subject you know how to teach, or improve an existing one.

## Optional

- [Full docs in one file](https://learn.ninja/llms-full.txt)
- [Home page as Markdown](https://learn.ninja/index.md)
- [Lesson JSON Schema](https://learn.ninja/schema/lesson.schema.json)
- [Skill index](https://learn.ninja/.well-known/skills/index.json)