It's freely available to anyone - the data (after securely hashing IPs) is provided as a service for everyone in the open podcast system.
There is a bit about the data api in the privacy policy [1]. Feel free to engage over on the github repo if you are blocked on anything or to chat about it [2].
The Open Podcast Prefix Project (OP3) is a free and open-source podcast prefix analytics service committed to open data and listener privacy.
It would be helpful to link "open data" to an op3.dev/opendata page that either defines data usage rights or states something like "podcast analytics data is intended for use by individual podcast publishers. For usage of aggregated data, please contact []". Maybe an FAQ with examples of acceptable commercial usage.
The "listener privacy" text could be linked to op3.dev/privacy.
Is there a license for the data provided by the API?
> The idea is not to allow the download of a complete database like PodcastIndex.org
Can an API data client publish a private or public mirror of the entire database?