It's only available at the [Crime Data API end point](https://crime-data-explorer.fr.cloud.gov/api), you have to first [request a data.gov api key](https://api.data.gov/signup/) then you can access it on

    https://api.usa.gov/crime/fbi/sapi/api/agencies?api_key=<api_key>

This is documented on the [GitHub project crime-data-api](https://github.com/fbi-cde/crime-data-api), and the official [Crime Data API page](https://crime-data-explorer.fr.cloud.gov/api).

On Dec 20, 2018, the result of the API call is 7.7MB of JSON.