Variables

Custom variables let one agent personalize every call. Define a variable once, use it as {{variable_name}} in your system prompt, welcome message, or final response, and pass its value when the agent is dispatched.

Define variables

Select Variables in the builder header to open Custom Variables, then select Add Variable.

Custom Variables panel with Type, Name, and Preview Value fields and an Add Variable button

Column	Description
Type	`String`, `Number`, or `Boolean`.
Name	The name you reference as `{{name}}`, for example `user_name`. Names must be unique.
Preview Value	The value used in test calls only, for example `John Doe`.

You can define up to 10 variables per agent.

Use variables

Type {{user_name}} in any supported field, or use Insert Variable above it.

Hi {{user_name}}, I see your order {{order_id}} is out for delivery.

Pass values in production

In production, pass the actual values in metadata.variables when you dispatch the agent to a room. Each entry’s name must match a variable you defined.

curl -X POST 'https://api.zeroruntime.ai/v2/agent/dispatch' \
  -H 'Authorization: YOUR_API_TOKEN' \
  -H 'Content-Type: application/json' \
  -d '{
    "meetingId": "abcd-efgh-ijkl",
    "agentId": "ag_7l0yt8",
    "metadata": {
      "variables": [
        { "name": "user_name", "value": "John Doe" },
        { "name": "order_id", "value": "ORD-1042" }
      ]
    }
  }'

meetingId is the room the agent joins. agentId is your agent’s ID.
The agent must be deployed.

Test calls from the Preview panel use each variable’s Preview Value instead.

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Define variables

Use variables

Pass values in production

​Define variables

​Use variables

​Pass values in production

Define variables

Use variables

Pass values in production