Defining functions

Functions are usually declared in the tools parameter of each API request. With tool search, your application can also load deferred functions later in the interaction. Either way, each callable function uses the same schema shape. A function definition has the following properties:

Field	Description
type	This should always be function
name	The function's name (for example, get_weather)
description	Details on when and how to use the function
parameters	JSON schema defining the function's input arguments
strict	Whether to enforce strict mode for the function call

Here is an example function definition for a get_weather function

{
  "type": "function",
  "name": "get_weather",
  "description": "Retrieves current weather for the given location.",
  "parameters": {
    "type": "object",
    "properties": {
      "location": {
        "type": "string",
        "description": "City and country e.g. Bogotá, Colombia"
      },
      "units": {
        "type": "string",
        "enum": ["celsius", "fahrenheit"],
        "description": "Units the temperature will be returned in."
      }
    },
    "required": ["location", "units"],
    "additionalProperties": false
  },
  "strict": true
}

Because the parameters are defined by a JSON schema, you can leverage many of its rich features like property types, enums, descriptions, nested objects, and recursive objects.