A good template to use as a reference is boilerplate-card

Requirements

For a plugin repository to be valid these are the requirements:

Repository structure

• There are .js files under ROOT_OF_THE_REPO/dist/ or directly in the root of the repository.
• One of the .js files have the same name as the repository.
  • With every rule there is an exception, if the repository's name starts with "lovelace-", there can be a .js file in the repository matching the repository name with "lovelace-" striped from the name, example:

Example

Repository name: "lovelace-awesome-card"

File name of one of the files: "awesome-card.js"

When searching for accepted files HACS will look in this order:

• The distdirectory.
• On the latest release.
• The root of the repository.

All .js files it finds in the first location it finds one that matches the name will be downloaded.

If your plugin require files that are not js files, place all files (including the card file) in the dist directory.

Import type

The readme in your repository should state if the plugin should be loaded as js or module.

example:

resources:

url: ....

type: js

GitHub releases (optional)

If there are releases

When installing/upgrading it will scan the content in the latest release.

If there are multiple releases in the repository the user have some options to install a specific version. The choices will be the last 5 releases and the default branch.

If there are no releases

It will scan files in the branch marked as default.