POST /api/v2/conversations/calls 400 error with auto-generated client

NICE CXone API & Integrations
1

Looking for advice on why my auto-generated client keeps throwing a 400 when executing POST /api/v2/conversations/calls. The OpenAPI spec defines toAddress as a simple string, yet the gateway rejects the payload with malformed participant address. I verified token rotation, confirmed the routing queue ID, and stripped whitespace from the SIP URI. The codegen templates use strict string serialization, so no extra escaping occurs. The gateway drops the request before routing. I suspect the underlying schema actually expects a nested object despite the spec claiming otherwise. Raw curl yields identical results. The SDK method conversationsApi.createConversationCall(req) returns the error immediately. Could spec version 2024-06-01 contain a typo that breaks the model generation pipeline? I need to know if I should patch the mustache templates to force a ConversationCall wrapper or if this is a platform validation quirk.

2

Take a look at at the fromAddress and toAddress schema. It expects tel: or sip: prefixes explicitly. The SDK often strips these if you pass a plain string. Try constructing the participant object manually in TypeScript:

const call = new PlatformClient.PostConversationsCallsCallbody();
call.fromAddress = { address: 'tel:+15550199', name: 'Bot' };
call.toAddress = { address: 'tel:+15550100', name: 'User' };

Warning: Ensure your OAuth token has the call:write scope, otherwise it throws 401, not 400.

3

TL;DR: The generated client likely omits the required name field in the participant object.

I usually solve this by bypassing the strict SDK model and sending the raw JSON payload directly to ensure the address object is fully formed.

payload = {
 "fromAddress": {"address": "tel:+15550199", "name": "Bot"},
 "toAddress": {"address": "sip:[email protected]", "name": "Target"},
 "routing": {"queueId": "your-queue-id"}
}
4

If I recall correctly, the Guest API WebSocket protocol enforces stricter schema validation than the standard REST endpoints, which explains why the auto-generated client fails. The 400 error usually stems from the SDK serializing the participant object incorrectly when the schema expects explicit tel: or sip: prefixes within the nested address object.

  • Construct the participant object manually rather than relying on the SDK’s auto-generation. This ensures the address string includes the required URI scheme and the name field is populated.
  • Verify that the OAuth token includes the conversations:call:write scope. The Guest API often requires explicit permissions even for internal routing tests.
  • Inspect the raw JSON payload before sending. The SDK might be omitting the routing object, which is mandatory for queue-based calls.

Here is a TypeScript snippet that works for me:

const payload = {
 fromAddress: { address: 'tel:+15550199', name: 'Widget' },
 toAddress: { address: 'sip:[email protected]', name: 'Agent' },
 routing: { type: 'queue', queueId: 'your-queue-id' }
};