Identifying ApigeeX generated errors

Hello, Apigee Community!

  1. Is there a way I can access the error.class property value from inside an Api Proxy policy or in a flow hook sharedflow ?

Error
error.class state type error Identifier

#### Properties

com.apigee.oauth.v2.OauthAdaptorVerificationException
PROXY_REQ_FLOW
ErrorPoint
Invalid ApiKey
fault
  1. What is the best way to identify (in a generic way) in a postproxy sharedfow that an error is ApigeeX generated and it is not an error from the backend sistem or any other custom error set in a previous step?

Thank you!