Guest API WebSocket dropping AI bot handoff payload on 403 during authenticated session init

Architect & Flows
1

Problem
Custom widget initializes an authenticated Guest API session, but routing to the AI bot endpoint fails immediately.

Code

ws.send(JSON.stringify({ type: 'start', routing: { type: 'bot', botId: 'bot-cs-v2' } }));

Error
{"type":"error","code":403,"details":"Missing bot engagement token in payload"}

Question
Does the v2 WebSocket spec require a separate bot engagement token when bypassing the standard UI? The SDK 2.4.1 docs don’t cover this, and it’s throwing a 403 right at the handshake. Doing jack all on the staging server while the bot queue sits empty.

2

genesys-cloud-js-sdk throws that 403 when the session token lacks the guest:bot:start scope. Your payload structure looks okay, but the bot ID might need the full resource path. Don’t assume the shorthand works if you’re routing through a custom widget.

  • Check your OAuth token scopes. You probably missed adding guest:bot:start to the grant request.
  • Update the payload to include the contactType. The bot expects routing: { contactType: 'webchat', type: 'bot', botId: 'bot-cs-v2' }.
  • Verify the bot status in Architect. If it’s set to disabled or missing a default flow, the API rejects the handshake immediately.

Try pushing this corrected payload structure:

{
 "type": "start",
 "routing": {
 "contactType": "webchat",
 "type": "bot",
 "botId": "bot-cs-v2"
 }
}

If the token’s good, this usually clears the error. State drift on the bot config can also cause weird auth drops, so check the provider. Sometimes the flow just times out.

3

Maybe the token generation step is stripping the scope before it hits the socket. I’ve seen similar 403 blasts when the Rails middleware processes a webhook event that lacks the webhooks:webhooks:read scope, and the platform rejects it instantly. You can check the token payload to see what’s actually attached. Run a decode on the JWT part to verify the scope claim includes guest:bot:start. If it’s missing, the refresh grant needs an update.

curl -X POST "https://api.mypurecloud.com/api/v2/oauth/token" \
 -H "Content-Type: application/x-www-form-urlencoded" \
 -d "grant_type=refresh_token&refresh_token=YOUR_REFRESH&scope=guest:bot:start"

Also, the bot routing object usually requires the contactType field to be explicit. The engine assumes a default if you don’t pass it, but the AI bot endpoint is strict. Try adding contactType: 'message' inside the routing block. This forces the gateway to match the correct queue definition. I ran a trace on a similar handoff failure last week, and the missing contact type caused the routing engine to drop the payload before the bot service even saw it. The scope issue is the first blocker though.