Computer Vision.
Clarifai API is a free Machine Learning API that requires OAuth authentication, is served over HTTPS and has unconfirmed CORS support.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
NLP API for text generation, embeddings, classification and summarization with a free trial tier
Yes. The Clarifai API is listed in the Machine Learning category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Clarifai API uses OAuth authentication, so you need to register for credentials before making requests.
CORS support for the Clarifai API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Clarifai API is served over HTTPS, so it's safe to use in production.