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3ab8cc7ada
This enables parallel tool calling w/ a combo of
1. Standard and structured response tool calls
2. Deferred (requiring human approval / edits) tool calls and structured
response tool calls
Hard to unit test w/ HITL right now end to end, so here's a repro of
things working w/ an integration test:
```py
from pydantic import BaseModel, Field
from langchain_core.tools import tool
from langchain_core.messages import HumanMessage
from langgraph.types import Command
from langgraph.checkpoint.memory import InMemorySaver
from langchain.agents.middleware_agent import create_agent
from langchain.agents.middleware.human_in_the_loop import HumanInTheLoopMiddleware
from langchain_openai import ChatOpenAI
class WeatherBaseModel(BaseModel):
temperature: float = Field(description="Temperature in fahrenheit")
condition: str = Field(description="Weather condition")
@tool
def add_numbers(a: int, b: int) -> int:
"""Add two numbers."""
return a + b
model = ChatOpenAI(model="gpt-4o-mini", temperature=0)
checkpointer = InMemorySaver()
agent = create_agent(
model=model,
tools=[add_numbers],
response_format=WeatherBaseModel,
middleware=[HumanInTheLoopMiddleware(tool_configs={"add_numbers": True})],
)
agent = agent.compile(checkpointer=checkpointer)
# First invocation should be interrupted due to human-in-the-loop middleware
response = agent.invoke(
{
"messages": [
HumanMessage(
"Add 1 and 2, then return the weather forecast with temperature 72 and condition sunny."
)
]
},
config={"configurable": {"thread_id": "1"}},
)
interrupt_description = response["__interrupt__"][0].value[0]["description"]
print(interrupt_description)
"""
Tool execution requires approval
Tool: add_numbers
Args: {'a': 1, 'b': 2}
"""
# Resume the agent with approval
response = agent.invoke(
Command(resume=[{"type": "approve"}]), config={"configurable": {"thread_id": "1"}}
)
for msg in response["messages"]:
msg.pretty_print()
"""
================================ Human Message =================================
Add 1 and 2, then return the weather forecast with temperature 72 and condition sunny.
================================== Ai Message ==================================
Tool Calls:
WeatherBaseModel (call_u6nXsEYRJbqNx4AEHgiQMpE2)
Call ID: call_u6nXsEYRJbqNx4AEHgiQMpE2
Args:
temperature: 72
condition: sunny
add_numbers (call_nuQEZF7PwfYDlVpnSt8eaInI)
Call ID: call_nuQEZF7PwfYDlVpnSt8eaInI
Args:
a: 1
b: 2
================================= Tool Message =================================
Name: WeatherBaseModel
Returning structured response: temperature=72.0 condition='sunny'
================================= Tool Message =================================
Name: add_numbers
3
"""
print(repr(response["response"]))
"""
WeatherBaseModel(temperature=72.0, condition='sunny')
"""
```