Idea created after response in ticket:
In Azure OpenAI it is possible for a “Content filter” to trigger and results in a 400 status code. https://go.microsoft.com/fwlink/?linkid=2198766
Instead of having the LLM process action in the flow give a -1 (unknown) and no other information, give it a different code or additionally some info that is was the “Content filter” that triggered. This way the error handling can be more user friendly in this situation.
