A few that impress me: - Github: https://docs.github.com/en/rest/guides/getting-started-with-... - Twilio: https://www.twilio.com/docs/usage/api - Stripe: https://stripe.com/docs/api

You may also appreciate reading Swagger's tips: https://swagger.io/blog/api-documentation/best-practices-in-... and reading up on Swagger in general.