POST /api/v2/conversations/calls 403 Forbidden on behalf of agent

Need some troubleshooting help with a 403 Forbidden response when attempting to initiate an outbound call on behalf of an agent using the Genesys Cloud Conversations API.

I am building a consumer-driven contract suite to validate provider behavior for a custom workforce engagement tool. The tool needs to place calls from a specific user context without requiring the agent to manually dial.

Here is the cURL snippet I am using in my Pact verification step:

curl -X POST \
 https://api.mypurecloud.com/api/v2/conversations/calls \
 -H 'Authorization: Bearer <VALID_OAUTH_TOKEN_WITH_CALL_INITIATE_SCOPE>' \
 -H 'Content-Type: application/json' \
 -d '{
 "to": "{{agent_user_id}}",
 "from": "{{outbound_number_id}}",
 "routing": {
 "queueId": "{{queue_id}}",
 "skill": {
 "id": "{{skill_id}}"
 }
 }
}'

The token is generated via client credentials flow with the call:outbound:initiate scope. The {{agent_user_id}} is a valid user ID belonging to an agent in the same organization. The {{outbound_number_id}} is a valid outbound number resource.

The response body is:

{
 "errors": [
 {
 "code": "forbidden",
 "message": "You do not have permission to perform this action."
 }
 ]
}

I have verified that the token has the correct scopes. The agent has the necessary permissions in the Genesys Cloud admin UI (Outbound Campaign permissions, etc.). I am running this test in the US/Pacific timezone, but that shouldn’t affect API permissions.

Is there a specific user capability or team membership required for the token’s associated user (or the agent user) to allow this API call? Or is this a known limitation of the on-behalf-of pattern in the Conversations API?

I need to ensure my Pact contracts reflect the correct provider expectations for this endpoint. Any insight into the permission model for this specific API call would be appreciated.

It depends, but generally…

The 403 usually means your service account lacks the specific conversation:call:write scope or isn’t mapped to the correct user role. Ensure your OAuth token includes conversation:call:write and user:read.

Also, verify the from and to parameters in the payload. The from user must exist and have a valid phone number.

Here is a corrected cURL example:

curl -X POST "https://api.mypurecloud.com/api/v2/conversations/calls" \
 -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
 -H "Content-Type: application/json" \
 -d '{
 "from": {
 "id": "AGENT_USER_ID"
 },
 "to": {
 "phoneNumber": "+1234567890"
 },
 "mediaType": "audio",
 "routing": {
 "type": "direct",
 "to": {
 "phoneNumber": "+1234567890"
 }
 }
 }'

Check your IAM policy too. If using AWS Lambda for this, ensure the environment variables for GC credentials are set correctly.

Debug the response body for specific error codes.

If I remember correctly, getting a 403 on outbound calls usually stems from scope mismatches rather than just missing the conversation:call:write permission. When using client_credentials for a service account to act on behalf of an agent, you often hit a wall because the token lacks the specific user context required for dialing. The suggestion above mentions user:read, but that is insufficient for initiating the call session itself. You likely need to switch to urn:ietf:params:oauth:grant-type:jwt-bearer to impersonate the agent directly, or ensure your service account has the conversation:call:write scope AND is assigned a role that allows outbound dialing via the API. If you stick with client_credentials, you might need to add user:read and conversation:call:write but also verify the from user in the payload has an active phone number and is not restricted by routing settings. Here is a corrected cURL using the jwt-bearer grant type to impersonate the agent, which usually resolves the 403 by providing the necessary user context:

curl -X POST "https://api.mypurecloud.com/api/v2/conversations/calls" \
 -H "Authorization: Bearer <agent_impersonation_token>" \
 -H "Content-Type: application/json" \
 -d '{
 "from": {
 "phoneNumber": "+15551234567",
 "name": "Agent Name"
 },
 "to": {
 "phoneNumber": "+15559876543"
 },
 "wrapUpCode": {
 "id": "standard"
 }
 }'

Ensure the <agent_impersonation_token> is obtained using the agent’s user ID and a service account with the user:read and conversation:call:write scopes. This approach bypasses the service account’s permission limitations by explicitly acting as the user. Also, double-check that the from number is configured in the Genesys Cloud telephony settings as an authorized outbound number.

Have you tried explicitly defining the ownerId in the payload?

{
 "to": "+15550199",
 "from": {
 "phoneNumber": "+15550100"
 },
 "ownerId": "the-agent-id-you-are-acting-for",
 "type": "external",
 "wrapUpCode": null,
 "monitor": false,
 "record": true,
 "outboundPhoneNumberId": "your-outbound-phone-number-id"
}

Coming from Five9, I assumed the token itself carried the user context if I had the right scopes. That assumption failed me here. The suggestion above is correct about needing conversation:call:write, but simply adding that to a service account token isn’t enough if the API doesn’t know who is making the call.

In CXone, when using client_credentials flow, the token represents the application, not a person. If you omit ownerId, the platform often defaults to checking if the service account itself has dialing privileges, which usually results in a 403 because service accounts don’t have phone numbers.

I hit this same wall last week while setting up a bulk dialer. My token had every scope under the sun, but the call still failed until I added the ownerId field. It tells the platform to simulate the call as if that specific agent clicked “dial.”

Also, double-check that the agent ID you pass in ownerId actually has an assigned phone number in the from object’s division. If the agent is in a different division than the outbound phone number, you might get a 400 or 403 depending on your security settings. It took me a few hours to debug that mismatch. Start with the ownerId tweak and see if the 403 clears up.

Ah, yeah, this is a known issue…

• The 403 is not a scope error; it is a permission boundary violation.
• Service accounts cannot impersonate agents via ownerId in the payload.
• You must use the /api/v2/users/{userId}/impersonate endpoint first.
• Generate a new access token using that user’s context.
• Use the impersonated token to call /api/v2/conversations/calls.