Update README

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

README.md

@@ -1,3 +1,44 @@
 # Actions Toolkit
 
 Toolkit for Docker (GitHub) Actions.
+
+## :test_tube: Experimental
+
+This repository is considered **EXPERIMENTAL** and under active development
+until further notice. It is subject to non-backward compatible changes or
+removal in any future version.
+
+## About
+
+This repository contains the source code for the toolkit that is consumed as
+a library by most of our GitHub Actions:
+
+* [docker/bake-action](https://github.com/docker/bake-action)
+* [docker/build-push-action](https://github.com/docker/build-push-action)
+* [docker/login-action](https://github.com/docker/login-action)
+* [docker/metadata-action](https://github.com/docker/metadata-action)
+* [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action)
+* [docker/setup-qemu-action](https://github.com/docker/setup-qemu-action)
+
+This toolkit provides some utilities and common logic when developing GitHub
+Actions and also acts as a minimal wrapper around our build tooling such as
+[Buildx](https://github.com/docker/buildx) and [BuildKit](https://github.com/moby/buildkit)
+and provides an easier API for interacting with them.
+
+## Installation
+
+```console
+$ npm install @docker/actions-toolkit
+```
+
+## Usage
+
+```js
+const { Toolkit } = require('@docker/actions-toolkit')
+const toolkit = new Toolkit()
+```
+
+## Contributing
+
+Want to contribute to the Actions Toolkit? Awesome! You can find information
+about contributing to this project in the [CONTRIBUTING.md](/.github/CONTRIBUTING.md)