Does “Talk to Assistant” ever trigger assistant-request, or is assistant-request only for inbound phone/SIP calls when no assistant is preselected? In other words, are Transient Assistants supported in the “Talk to Assistant” flow?

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Based on the documentation I have found,

assistant-request

webhooks are only triggered for inbound phone or SIP calls when no assistant is preselected. There is no information confirming that the "Talk to Assistant" (Web) feature triggers these webhooks or supports transient assistants in that flow. If you need dynamic assistant selection or transient assistants, use the inbound phone/SIP call flow with a server URL configured as shown below:

js
// Example: Responding to assistant-request for inbound calls
app.post("/webhooks/vapi", (req, res) => {
  if (req.body?.message?.type === "assistant-request") {
    return res.json({ assistant: { /* transient assistant config */ } });
  }
  res.sendStatus(204);
});

For web-based "Talk to Assistant," please consult Vapi support for the latest capabilities. Source: - [Spam call rejection (assistant-request & transient assistants)](https://docs.vapi.ai/server-url/spam-call-rejection)

Hi Sooz, assistant-request webhooks are only sent for inbound phone/SIP call flows when Vapi needs you to provide an assistant (e.g., no assistant pre-selected). The web "Talk to Assistant" flow does not trigger assistant-request, and the web widget accepts an assistant configuration directly (transient assistants are not supported via assistant-request in web calls). For dynamic/transient assistant selection on the web, pass the assistant configuration inline to the widget or chat API; for server-driven transient assistants use the inbound phone/SIP assistant-request webhook as in your example. Relevant docs: - Session & chat quickstart: https://docs.vapi.ai/chat/quickstart - assistant-request / inbound call behavior described in Server URL / spam-call-rejection (as you referenced) - Related note from support threads: assistant-request is only for phone calls (not web), and the widget must be passed assistants directly.