Question

Why does my chatbot fail after switching from API key authentication to OAuth login

Answer 1

When the chatbot works with an API key , and starts failing after switching to OAuth /Extra ID authentication ,the issue is usually one of these
1. Wrong token audience :(scope/resources)
For microsoft azure openAI the token which must be used is https://cognitiveservices.azure.com/.default

2. Using ID token instead of access token
OAuth login often returns
A. ID TOKEN 

B. REFRESH TOKEN 

C. ACCESS TOKEN 

 AND azure requires an access token , not ID token .

3. When the token expires and requires logic is missing 

API key never misses key quickly. OAuth access token usually expires in an hour 

So we need an automatic token refresh .

4.Service principal /managed identity lacks azure role 

With API keys,RBAC is bypassed .

With the OAuth key , Azure RBAC matters.