AC xApp: Uses the E2 simulator used to test the RIC located in it/test (/test/simulators/e2sim). The simulator allows the xApp to subscribe to the SGNB ADDITION REQUEST message and generates INDICATION with the payload.
MC xApp: Uses build it generator of X2 messages in protobuf format.
ML xApp: ?
KPI Mon: Plan is to use the E2 simulator in it/test with a new ASN.1 message payload.