https://help.github.com/ja/actions/automating-your-workflow-with-github-actions/creating-a-javascript-action を参考にしている

Hello world javascript action

This action prints "Hello World" or "Hello" + the name of a person to greet to the log.

Inputs

who-to-greet

Required The name of the person to greet. Default "World".

Outputs

time

The time we greeted you.

Example usage

uses: actions/hello-world-javascript-actions@v1
with:
  who-to-greet: 'Mona the Octocat'