[1] W3C API Overview ( 版) <https://w3c.github.io/w3c-api/>
There are two ways to do that:
Using the apikey query parameter: https://api.w3.org/groups?apikey=mgug2t7fylcksswc4gcs08s4gooo0ok
Using the HTTP Authorization header: Authorization: W3C-API apikey="mgug2t7fylcksswc4gcs08s4gooo0ok"
[3] 401 応答に WWW-Authenticate:
は含まれないようです。