diff --git a/README.md b/README.md
index 2c62394..4dc9013 100644
--- a/README.md
+++ b/README.md
@@ -5,6 +5,19 @@ Twitter OpenAPI(Swagger) specification
 - [Dart](https://github.com/fa0311/twitter_openapi_dart)
 - [React Documents](https://github.com/fa0311/twitter-openapi-docs)
 
+## Usage
+
+```shell
+openapi-generator-cli generate -g <language> -i https://raw.githubusercontent.com/fa0311/twitter-openapi/main/dist/openapi-3.0.yaml -o ./generated
+```
+
+Note that the license also inherits to the output.
+
+## Contribute
+
+- `src` *.yaml files should be written according to the [v3.0/schema.json](https://raw.githubusercontent.com/OAI/OpenAPI-Specification/main/schemas/v3.0/schema.json)
+- `dist` Do not rewrite this file as it is an automatically generated OpenAPI file.
+
 ## License
 
 [agpl-3.0](./LICENSE.txt)