@RC
In addition to the "say" message type, VAPI may support various other message types depending on its capabilities and the specific implementation. Common message types in voice APIs often include:
- `play`: to play an audio file.
- `record`: to record the caller's voice.
- `gather`: to collect digits input by the caller.
- `redirect`: to redirect the call to another URL or function.
- `hangup`: to end the call.
However, since I don't have the specific details of all the message types supported by VAPI, please ask support for more info on this to get a comprehensive list of message types and their respective JSON structures.