A REXX exec in TSO/E can issue TSO/E commands, APPC/MVS calls, MVS™ module invocations, ISPF commands, and ISPF/PDF EDIT commands. If you have TSO/E CONSOLE command authority and an extended MCS console session is active, you can also issue MVS system and subsystem commands in a REXX exec. Each type of invocation is associated with a different host command environment.