----------------------------- **While I generate an answer, here are some sources that might be helpful**: * [Phone Calling]() * [Get Call]() * [Create Phone Call]() * [List Calls]() -----------------------------

### Answer In the context of Vapi, the operation and configuration of outbound calls, including setting or changing caller ID attributes, adhere strictly to Vapi's defined parameters and capabilities. When interfacing with telephony providers like Twilio through Vapi, you utilize Vapi's functionalities and limitations, which might not directly map to every feature or parameter available through the provider's native API or service interface. Regarding the specific "From" parameter for changing the caller ID on outbound calls as you'd do directly with Twilio, Vapi's documentation or the provided information sources do not explicitly detail the process for altering the caller ID or passing through such parameters directly in the same manner as Twilio's API allows. This suggests that attempting to directly transfer or mimic Twilio's "From" parameter functionality through Vapi without adhering to Vapi's specific API structure and parameter requirements might lead to errors or unsupported operation notifications, such as the one you encountered. Vapi's documentation and API reference guide the configuration and execution of outbound calls through its platform, emphasizing the use of Vapi's defined parameters and structures. If you are integrating Twilio with Vapi for outbound calls, ensuring compatibility and supported operation within Vapi's framework is crucial. For detailed guidance or if looking to implement functionalities like changing the caller ID that directly leverages provider-specific features not documented within Vapi's scope, reviewing Vapi's documentation or consulting with their support for tailored advice might be necessary. For outbound calls with Vapi, you typically work within the guidelines and parameters provided by Vapi's API documentation, such as setting up an assistant, defining the phone number to use (through either purchasing or importin

g numbers into Vapi), and configuring the call details accordingly [(1)]() [(2)]() [(3)]() . If the functionality you seek (like modifying the "From" parameter directly as you would in Twilio) falls outside the documented capabilities or generates errors, it indicates a need to adjust the approach within the constraints and supported features of Vapi's platform.

Got it. Tagging @User for additional help.

it is becoming a blocker now for our project