# Supervisor API

> The REST API of the Supervisor, that Home Assistant Core, the command line, and apps use to manage the system, apps, backups, and updates.

Source: https://contributors.home-assistant.io/glossary/supervisor-api/

- In code: `http://supervisor/`, `SUPERVISOR_TOKEN`, `hassio_api`

Inside an app, the API is at `http://supervisor/`, and the Supervisor gives every app its own token in the `SUPERVISOR_TOKEN` environment variable. What an app may call depends on what it asks for in its configuration, like `hassio_api: true`.

Many paths still use the old name of apps, like `/addons`. See the [Supervisor API reference](https://contributors.home-assistant.io/apps/supervisor-api/).

## Related terms

- [Supervisor](https://contributors.home-assistant.io/glossary/supervisor/): The part of Home Assistant OS that runs Home Assistant Core and apps, each in its own container, and handles their updates and backups.
- [App](https://contributors.home-assistant.io/glossary/app/): Extra software that runs next to Home Assistant on Home Assistant OS, like an MQTT broker or a file editor.
- [Bashio](https://contributors.home-assistant.io/glossary/bashio/): A library of Bash functions for apps, with helpers for reading the app's options, logging, and talking to the Supervisor API.