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<@1145576664366055464> Error: 400 Bad Request
{"status":"error","message":"Start node id does not exist in node ids"}

Thanks for tagging me <@1247202314565976215>. I'll look through relevant sources and get back to you shortly.

### Answer
 

This error occurs when the `start_node_id` you specified does not match any `id` in your `nodes` array. [(1) ](<https://docs.retellai.com/api-references/create-conversation-flow>)

When creating or updating a conversation flow, the `start_node_id` must reference an existing node. [(2) ](<https://docs.retellai.com/api-references/update-conversation-flow>) , [(1) ](<https://docs.retellai.com/api-references/create-conversation-flow>)

For example, if your `start_node_id` is `"start"`, you must have a node with `"id": "start"` in your nodes array: 

```javascript
const conversationFlowResponse = await client.conversationFlow.create({
  model_choice: { model: 'gpt-4.1', type: 'cascading' },
  nodes: [
    {
      id: 'start',
      instruction: { text: 'Greet the customer and ask how you can help them.', type: 'prompt' },
      type: 'conversation',
    },
  ],
  start_speaker: 'agent',
}) ;
```


**To fix this:**
1. Check your `start_node_id` value 
2. Ensure a node with that exact `id` exists in your `nodes` array 
3. Node IDs are case-sensitive, so verify the casing matches exactly

​
To learn more, see the sources I considered:

[[1] Create Conversation Flow](https://docs.retellai.com/api-references/create-conversation-flow)
[[2] Update Conversation Flow](https://docs.retellai.com/api-references/update-conversation-flow)
​

Feel free to tag <@1145576664366055464> with additional questions. I also appreciate feedback, it helps me improve.