create_react_agent takes more time compared to it's sync method

[BrownsugarZeer]

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Example Code

import time
import asyncio
from langchain_core.messages import HumanMessage
from langchain_core.tools import tool
from langchain_openai import ChatOpenAI
from langgraph.prebuilt.chat_agent_executor import create_react_agent

model = ChatOpenAI(
    model="gpt-4o-mini",
    temperature=0.0,
)


@tool
def add(x: int, y: int):
    """Add two numbers."""
    time.sleep(2)
    return x + y


@tool
def mul(x: int, y: int):
    """Multiply two numbers."""
    time.sleep(2)
    return x * y


@tool
async def aadd(x: int, y: int):
    """Add two numbers."""
    await asyncio.sleep(2)
    return x + y


@tool
async def amul(x: int, y: int):
    """Multiply two numbers."""
    await asyncio.sleep(2)
    return x * y


async def foo():
    agent = create_react_agent(
        model,
        [aadd, amul],
    )
    inputs = {"messages": [HumanMessage(content="(2+3)*4")]}
    async for s in agent.astream(inputs, stream_mode="values"):
        s["messages"][-1].pretty_print()


start_time = time.time()
asyncio.run(foo())
end_time = time.time()
print(f"Asynchronous execution time: {end_time - start_time:.2f} seconds")


def foo2():
    agent = create_react_agent(
        model,
        [add, mul],
    )
    inputs = {"messages": [HumanMessage(content="(3+4)*5")]}
    for s in agent.stream(inputs, stream_mode="values"):
        s["messages"][-1].pretty_print()


start_time = time.time()
foo2()
end_time = time.time()
print(f"Synchronous execution time: {end_time - start_time:.2f} seconds")

Description

It seems that no asynchronous when calling the time expensive function we assumed.

================================ Human Message =================================

(2+3)*4
================================== Ai Message ==================================
Tool Calls:
  aadd (call_Cp1f8TLeWvh1oPaMe869CJ0L)
 Call ID: call_Cp1f8TLeWvh1oPaMe869CJ0L
  Args:
    x: 2
    y: 3
  amul (call_MaFta75Pwx4vkrIdDag6Usmy)
 Call ID: call_MaFta75Pwx4vkrIdDag6Usmy
  Args:
    x: 5
    y: 4
================================= Tool Message =================================
Name: amul

20
================================== Ai Message ==================================

The result of \((2 + 3) \times 4\) is \(20\).
Asynchronous execution time: 5.29 seconds
================================ Human Message =================================

(3+4)*5
================================== Ai Message ==================================
Tool Calls:
  add (call_rPHe6neuP0sOuODgPuqqEsV6)
 Call ID: call_rPHe6neuP0sOuODgPuqqEsV6
  Args:
    x: 3
    y: 4
  mul (call_8Ck7xdWrNrmPAMR8uAqS8CuR)
 Call ID: call_8Ck7xdWrNrmPAMR8uAqS8CuR
  Args:
    x: 7
    y: 5
================================= Tool Message =================================
Name: mul

35
================================== Ai Message ==================================

The result of \((3 + 4) \times 5\) is \(35\).
Synchronous execution time: 4.50 seconds

System Info

System Information

OS: Windows
OS Version: 10.0.22631
Python Version: 3.10.9 (tags/v3.10.9:1dd9be6, Dec 6 2022, 20:01:21) [MSC v.1934 64 bit (AMD64)]

Package Information

langchain_core: 0.3.19
langchain: 0.3.2
langchain_community: 0.3.1
langsmith: 0.1.131
langchain_chroma: 0.1.4
langchain_experimental: 0.3.3
langchain_openai: 0.2.2
langchain_text_splitters: 0.3.0
langchainhub: 0.1.21
langgraph: 0.2.53

Optional packages not installed

langserve

Other Dependencies

aiohttp: 3.10.5
async-timeout: 4.0.3
chromadb: 0.5.11
dataclasses-json: 0.6.7
fastapi: 0.114.2
httpx: 0.27.2
jsonpatch: 1.33
langgraph-checkpoint: 2.0.4
langgraph-sdk: 0.1.36
numpy: 1.26.4
openai: 1.45.1
orjson: 3.10.7
packaging: 24.1
pydantic: 2.9.1
pydantic-settings: 2.5.2
PyYAML: 6.0.2
requests: 2.32.3
requests-toolbelt: 1.0.0
SQLAlchemy: 2.0.35
tenacity: 8.5.0
tiktoken: 0.7.0
types-requests: 2.32.0.20240914
typing-extensions: 4.12.2