### Answer To set up your inbound call webhook response, your endpoint needs to return a JSON response with a successful status code (2xx) . [(1) ]() ## Response Format The response fields should be grouped under

call_inbound

. All fields are optional: - `override_agent_id`: override the agent for this call - `override_agent_version`: override the agent version - `dynamic_variables`: set dynamic variables for the call - `metadata`: set metadata for the call - `agent_override`: override agent settings per-call ## Example Response

json
{
  "call_inbound": {
    "override_agent_id": "agent_12345",
    "override_agent_version": 1,
    "dynamic_variables": {
      "customer_name": "John Doe"
    },
    "metadata": {
      "random_id": "12345"
    }
  }
}

## Setup Steps 1. Set the

inbound_webhook_url

on your phone number configuration [(2) ]() , [(3) ]() 2. Your webhook endpoint must respond within 10 seconds with a 2xx status [(1) ]() 3. If the webhook fails, it retries up to 3 times To reject an inbound call, respond with a 200 status code without the

override_agent_id

field. Note: The inbound webhook is configured at the phone number level, not the agent level. [(7) ]()

​ To learn more, see the sources I considered: [[1] Inbound webhook](https://docs.retellai.com/features/inbound-call-webhook) [[2] Import Phone Number](https://docs.retellai.com/api-references/import-phone-number) [[3] Update Phone Number](https://docs.retellai.com/api-references/update-phone-number) ​

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

### Answer Your JSON structure looks correct. The issue is likely that the values like

{{201.statusCharacter}}

are template placeholders from your automation tool (like Make or N8N) that need to be resolved to actual string values before being sent to Retell. [(1) ]() All values in dynamic variables must be **strings**—numbers, booleans, or other data types are not supported. [(2) ]() Checklist: 1. **Ensure placeholders are resolved**: Your automation tool should replace

{{201.statusCharacter}}

with the actual value (e.g.,

"active"

) before sending the response to Retell. 2. **Verify response timing**: The webhook has a timeout of 10 seconds. If no success status (2xx) is received within that time, it will retry. [(1) ]() 3. **Check your automation logs**: Confirm the actual JSON being sent has resolved values, not the raw template syntax. Example of what Retell should receive:

json
{
  "call_inbound": {
    "dynamic_variables": {
      "status": "active",
      "customer_id": "12345",
      "customer_name": "John Doe"
    }
  }
}

, [(3) ]() , [(4) ]() If your automation tool is sending the literal

{{201.statusCharacter}}

text instead of resolved values, the agent will receive those as the actual variable values.

​ To learn more, see the sources I considered: [[1] Inbound webhook](https://docs.retellai.com/features/inbound-call-webhook) [[2] Dynamic Variables](https://docs.retellai.com/build/dynamic-variables) [[3] inbound webhook](https://discord.com/channels/1186424376300679209/1352358246371037276) [[4] Not receiving response from inbound webhook.](https://discord.com/channels/1186424376300679209/1355901739244585132) ​

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

### Answer Based on similar issues reported by other users, the problem may be with how the response is structured. [(1) ]() Try changing your response format to explicitly nest

dynamic_variables

under

call_inbound

like this:

json
{
  "call_inbound": {
    "dynamic_variables": {
      "status": "active",
      "customer_id": "12345",
      "customer_name": "John Doe"
    }
  }
}

One user reported that using

retell_llm_dynamic_variables

was not setting the variables correctly, and what fixed it was using the

call_inbound.dynamic_variables

structure instead. To verify the variables are being received: 1. Add one of your dynamic variables to the begin message (e.g.,

"Hello {{customer_name}}"

) to confirm the agent is receiving them. [(2) ]() 2. If it works in the begin message but not in the prompt, that indicates the variables are arriving but may not be referenced correctly in your prompt. In your prompt, make sure you're referencing the variables using the

{{variable_name}}

syntax, like: [(3) ]()

The customer's name is {{customer_name}} and their status is {{status}}.

If the agent speaks the variable correctly in the begin message but not in the prompt responses, try explicitly instructing the agent to use those variables in a "Context" section of your prompt. [(2) ]()

​ To learn more, see the sources I considered: [[1] Dynamic Variables](https://discord.com/channels/1186424376300679209/1356680357084135558) [[2] Dynamic Variables](https://discord.com/channels/1186424376300679209/1340177140204699649) [[3] Dynamic Variables](https://docs.retellai.com/build/dynamic-variables) ​

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