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Parallel Tools

Parallel Tool Calling is a feature that allows you to call multiple functions in a single request. This makes it faster to get a response from the language model, especially if your tool calls are independent of each other.

Experimental Feature

Parallel tool calling is only supported by Gemini and OpenAI at the moment

Understanding Parallel Function Calling

By using parallel function callings that allow you to call multiple functions in a single request, you can significantly reduce the latency of your application without having to use tricks with now one builds a schema.

from __future__ import annotations

import openai
import instructor

from typing import Iterable, Literal
from pydantic import BaseModel


class Weather(BaseModel):
    location: str
    units: Literal["imperial", "metric"]


class GoogleSearch(BaseModel):
    query: str


client = instructor.from_openai(
    openai.OpenAI(), mode=instructor.Mode.PARALLEL_TOOLS
)  # (1)!

function_calls = client.chat.completions.create(
    model="gpt-4o-mini",
    messages=[
        {"role": "system", "content": "You must always use tools"},
        {
            "role": "user",
            "content": "What is the weather in toronto and dallas and who won the super bowl?",
        },
    ],
    response_model=Iterable[Weather | GoogleSearch],  # (2)!
)

for fc in function_calls:
    print(fc)
    #> location='Toronto' units='metric'
    #> location='Dallas' units='imperial'
    #> query='who won the super bowl'
import instructor
import vertexai
from vertexai.generative_models import GenerativeModel
from typing import Iterable, Literal
from pydantic import BaseModel

vertexai.init()

class Weather(BaseModel):
    location: str
    units: Literal["imperial", "metric"]


class GoogleSearch(BaseModel):
    query: str


client = instructor.from_vertexai(
    GenerativeModel("gemini-1.5-pro-preview-0409"),
    mode=instructor.Mode.VERTEXAI_PARALLEL_TOOLS
)  # (1)!

function_calls = client.create(
    messages=[
        {
            "role": "user",
            "content": "What is the weather in toronto and dallas and who won the super bowl?",
        },
    ],
    response_model=Iterable[Weather | GoogleSearch],  # (2)!
)

for fc in function_calls:
    print(fc)
    #> location='Toronto' units='metric'
    #> location='Dallas' units='imperial'
    #> query='who won the super bowl'
  1. Set the mode to PARALLEL_TOOLS to enable parallel function calling.
  2. Set the response model to Iterable[Weather | GoogleSearch] to indicate that the response will be a list of Weather and GoogleSearch objects. This is necessary because the response will be a list of objects, and we need to specify the types of the objects in the list.

Noticed that the response_model Must be in the form Iterable[Type1 | Type2 | ...] or Iterable[Type1] where Type1 and Type2 are the types of the objects that will be returned in the response.