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Overview

Humanlayer integrates seamlessly with CrewAI to add human oversight to your AI applications. This guide shows you how to use Humanlayer with CrewAI.

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Installation

Install the required packages:

pip install humanlayer crewai crewai-tools python-dotenv

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Basic Example

Let’s create a simple math agent that performs basic arithmetic operations with human oversight.

from dotenv import load_dotenv
from crewai import Agent, Crew, Task
from crewai_tools import tool

load_dotenv()

from humanlayer import HumanLayer

hl = HumanLayer(
    # run_id is optional - it can be used to identify the agent in approval history
    run_id="crewai-math",
)

@tool
def add(a: int, b: int) -> int:
    """Add two numbers together."""
    return a + b

@tool
@hl.require_approval()
def multiply(a: int, b: int) -> int:
    """multiply two numbers"""
    return a * b

general_agent = Agent(
    role="Math Professor",
    goal="""Provide the solution to the students that are asking
    mathematical questions and give them the answer.""",
    backstory="""You are an excellent math professor that likes to solve math questions
    in a way that everyone can understand your solution""",
    allow_delegation=False,
    tools=[add, multiply],
    verbose=True,
    crew_sharing=False,
)

task = Task(
    description="multiply 2 and 5, then add 32 to the result",
    agent=general_agent,
    expected_output="A numerical answer.",
)

crew = Crew(agents=[general_agent], tasks=[task], verbose=True)

if __name__ == "__main__":
    result = crew.kickoff()
    print("\n\n---------- RESULT ----------\n\n")
    print(result)

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How it Works

  1. We create a HumanLayer instance with an optional run_id to identify this agent in the approval history
  2. Define two math functions as CrewAI tools using the @tool decorator
  3. Use @hl.require_approval() to require human approval before the multiply function can be called
  4. Create a CrewAI agent with these tools and a task to perform
  5. The agent will request approval before executing the multiply function

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Running the Example

  1. Set up your environment variables in .env
  2. Run the example:
python main.py

When the agent attempts to use the multiply function, it will pause and request human approval through your configured contact channel (Slack, Email, etc).

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Next Steps

For more framework examples, see https://github.com/humanlayer/humanlayer/tree/main/examples