# Building an API Product

Sell access to your data or services through a managed API with authentication, rate limiting, and usage-based billing.

## What You Get

- API endpoints generated from your entities and actions
- API key management for your customers
- Usage tracking and rate limiting
- Billing tied to API usage
- Documentation (auto-generated)

## Example: Data API

1. Define entities for your data (Products, Locations, Prices)
2. Enable API as a Service
3. Set up billing: Free (100 calls/day), Pro (10,000 calls/day, $49/month)
4. Map API call limits to plans
5. Deploy

Your customers sign up, get API keys, and start querying your data. You track usage and bill accordingly.