Azure Face Liveness API started failing today with error 400 requiring a JSON body, but documentation shows no body parameters—have API requirements changed?

Question

Our Azure Face Liveness API stopped working today (from 5:59AM AWST). We are now receiving error 400: “Request body must be a JSON object.” The official documentation does not show a request body or body parameters, and our implementation (which has been working without a body) has not changed. Can you confirm if API parameters were changed and connect us with the responsible technical team so we can restore our liveness service?

Documentation reference: https://learn.microsoft.com/en-us/azure/ai-services/computer-vision/tutorials/liveness-quick-link

Answer 1

There were some recent un-documented changes to the current API version. According to the official documentation, a request body has never been required. However, the only way to make the service function now is by adding an empty JSON object ({}) to the request body and including the header Content-Type: application/json, effectively “pretending” a body exists. Hope this helps anyone else.