### Answer Based on the available documentation, the Create Outbound SMS API does not include a parameter to directly override the first message content. [(1) ]() The initial SMS message is automatically generated and sent based on the agent's configuration. However, you can use

retell_llm_dynamic_variables

to inject dynamic variables into your agent's prompt, which may influence the generated first message:

javascript
const chatResponse = await client.chat.createSMSChat({
  from_number: '+12137771234',
  to_number: '+14155551234',
  retell_llm_dynamic_variables: {
    customer_name: 'John Doe'
  }
}) ;

To customize the first message, you would need to configure your chat agent's prompt/configuration to produce the desired initial message content. Check out these potentially useful sources for more details: - [Create Outbound SMS]() - [Send & receive SMS]() Would you like me to try to provide a general answer on other approaches?

​ To learn more, see the sources I considered: [[1] Create Outbound SMS](https://docs.retellai.com/api-references/create-sms-chat) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.