Start with the quickstart. The API reference lists every endpoint and field.
Create an account, get an API key and make your first call with curl.
Send your key in the X-Api-Key header, and keep it on your server.
Problem details, every error code, and when to retry.
60 requests per minute per key, and what a 429 means.
Pages, page sizes, sorting and the 10,000-result limit on search.
Where the data comes from, how old it is, and how to check.
Every change to the API, dated.