> For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt.

# Modern.js For AI

Modern.js provides a toolkit for AI agents that makes your project agent-ready out of the box, helping you use AI to develop, upgrade, and migrate Modern.js applications more accurately and efficiently.

## Bundled docs

Modern.js ships the English docs that match your installed version together with `@modern-js/app-tools`. After you install or upgrade, they live at `node_modules/@modern-js/app-tools/docs/`, available offline with no extra setup.

AI agents use them to get APIs, config, and conventions that exactly match your framework version, rather than relying on potentially outdated training data.

## AGENTS.md

`AGENTS.md` gives AI coding agents project-level guidance — telling them to read the bundled docs before making changes and to follow Modern.js conventions. A `CLAUDE.md` is generated alongside it, reusing the same guidance for Claude Code via the `@AGENTS.md` import.

- **New projects**: `npx @modern-js/create` generates both files by default; pass `--no-agents-md` to skip them.
- **Existing projects**: run `npx @modern-js/create --agents-md-only` at the project root to create or update them. Re-run it any time; your own additions are preserved.

Modern.js only maintains the content inside the `<!-- BEGIN:modernjs-agent-rules -->` markers in `AGENTS.md`; anything you write outside them is left untouched.

## llms.txt

llms.txt is an online documentation index following the [llms.txt specification](https://llmstxt.org/), auto-generated by [`@rspress/plugin-llms`](https://rspress.rs/plugin/official-plugins/llms) for AI tools to retrieve the full docs online:

- Index: [`https://modernjs.dev/llms.txt`](https://modernjs.dev/llms.txt)
- Full text: [`https://modernjs.dev/llms-full.txt`](https://modernjs.dev/llms-full.txt) (large — fetch on demand)

Use it when you need content beyond the bundled docs — just let your agent retrieve it on demand, no need to copy docs into your project. Typical cases: looking up another framework version, a section not included in the bundle, or getting Modern.js information outside of a project (for example before a project exists, or when researching on its own).

## Skills

Skills are on-demand AI capabilities following the [Agent Skills open standard](https://github.com/vercel-labs/skills). User-facing Skills:

| Skill           | Identifier                | Description                                                                                     |
| --------------- | ------------------------- | ----------------------------------------------------------------------------------------------- |
| Upgrade to v3   | `modernjs-migrate-to-v3`  | Migrate a v2 app to v3: safe rewrites + manual checklist + migration report                     |
| Enable features | `modernjs-feature-enable` | Enable BFF / SSG / styled-components for v3 apps, and scaffold Tailwind CSS / custom Web Server |

> Skills are not force-installed or implicitly installed — you install them explicitly. RSC and micro-frontend setups are configuration or architecture decisions, not one-click `modernjs-feature-enable` actions.

## Installing Skills

Modern.js user-facing Skills live in the repo's root `skills/` directory and follow the [Agent Skills open standard](https://github.com/vercel-labs/skills). The recommended way is the standard `skills` CLI, installing straight from GitHub:

```bash
# List installable Skills
npx skills add web-infra-dev/modern.js --list

# Install a single Skill into your agent directory (--agent: claude-code / codex / cursor / ...)
npx skills add web-infra-dev/modern.js --skill modernjs-migrate-to-v3 --agent codex -y
```

It installs the entire Skill directory (`SKILL.md` + `scripts/` + `references/`) into the corresponding agent directory, ready to trigger there.

> To pin a specific version, append `#<ref>` (a tag, branch, or commit) to the repo — it installs the Skill as of that ref (replace `<tag>` with a release tag that contains this Skill):
>
> ```bash
> npx skills add web-infra-dev/modern.js#<tag> --skill modernjs-migrate-to-v3 --agent codex -y
> ```