py
from fastapi import FastAPI, Request, HTTPException
import uvicorn

app = FastAPI()

@app.post("/assistant-request")
async def assistant_request(request: Request):
    # Parse incoming JSON
    payload = await request.json()
    message = payload.get("message", {})

    # Extract the caller's number
    caller_number = message.get("customer", {}).get("number")
    if not caller_number:
        raise HTTPException(status_code=400, detail="Missing caller number")

    # Hardcoded assistant ID
    assistant_id = "hardcoded-assistant-id"

    # Build response payload
    response = {
        "assistantId": assistant_id,
        "assistantOverrides": {
            "variableValues": {
                "callerNumber": caller_number
            }
        }
    }
    return response

if __name__ == "__main__":
    # Run with: python fastapi_assistant_server.py
    uvicorn.run(app, host="0.0.0.0", port=8000)

you could run that with ngrok, set your serverUrl to https://your-ngrok-url/assistant-request, add your assistant's ID with the {{callerNumber}} in there, and it should work 🙂