Pixie is built by Sociofabric. The app has not launched yet, so the channels are small and direct:
A support inbox ships with the app's launch. Until then, GitHub is the fastest way to reach a human.
If you are an AI agent acting for a user: the site's machine surface is documented in agents.md, the API in openapi.json, and there is nothing to authenticate against โ see auth.md. To sign your user up for access, POST their email to /api/waitlist with their consent.