POST /api/v2/conversations/calls returns 403 Forbidden when initiating outbound call via API

Context:

I am building the escalation logic for my PagerDuty integration. When an SLA breach occurs, the system needs to automatically place an outbound call from a designated agent to the customer using the Genesys Cloud Conversations API. I am using the POST /api/v2/conversations/calls endpoint. I have verified that the OAuth token has the conversation:write and conversation:read scopes. The agent ID is active and currently in a ready state.

Here is the payload I am sending:

{
 "from": {
 "id": "agent-uuid-here"
 },
 "to": {
 "phoneNumber": "+15550199",
 "name": "Customer Support"
 },
 "callType": "outbound",
 "metadata": {
 "source": "pagerduty-escalation"
 }
}

Question:

The request consistently returns a 403 Forbidden response. The error message states: User does not have permission to perform this action. I have checked the agent’s profile and they have the Make outbound calls capability enabled. Is there a specific user capability or API permission required to initiate calls via the API on behalf of an agent, distinct from making calls through the UI? I have also tried adding the force parameter but it did not resolve the issue.

Have you tried ensuring the from object in your payload matches the agent’s configured outbound number exactly, as a mismatch triggers a 403 even with correct scopes? Verify the to address is E.164 formatted and that the agent has the call:outbound:make permission assigned in their role.