adk-python/contributing/samples/crewai_tool_kwargs

CrewAI Tool **kwargs Parameter Handling

This sample demonstrates how CrewaiTool correctly handles tools with **kwargs parameters, which is a common pattern in CrewAI tools.

What This Sample Demonstrates

Key Feature: **kwargs Parameter Passing

CrewAI tools often accept arbitrary parameters via **kwargs:

def _run(self, query: str, **kwargs) -> str:
    # Extra parameters are passed through kwargs
    category = kwargs.get('category')
    date_range = kwargs.get('date_range')
    limit = kwargs.get('limit')

The CrewaiTool wrapper detects this pattern and passes all parameters through (except framework-managed ones like self and tool_context).

Contrast with Regular Tools

For comparison, tools without **kwargs only accept explicitly declared parameters:

def _run(self, query: str, category: str) -> str:

Prerequisites

Required: CrewAI Tools (Python 3.10+)

pip install 'crewai-tools>=0.2.0'

Required: API Key

export GOOGLE_API_KEY="your-api-key-here"
# OR
export GOOGLE_GENAI_API_KEY="your-api-key-here"

Running the Sample

Option 1: Run the Happy Path Test

cd contributing/samples/crewai_tool_kwargs
python main.py

Expected output:

============================================================
CrewAI Tool **kwargs Parameter Test
============================================================

🧪 Test 1: Basic search (no extra parameters)
User: Search for Python tutorials
Agent: [Uses tool and returns results]

🧪 Test 2: Search with filters (**kwargs test)
User: Search for machine learning articles, filtered by...
Agent: [Uses tool with category, date_range, and limit parameters]

============================================================
✅ Happy path test completed successfully!
============================================================

What Gets Tested

✅ CrewAI tool integration - Wrapping a CrewAI BaseTool with ADK ✅ Basic parameters - Required query parameter passes correctly ✅ **kwargs passing - Extra parameters (category, date_range, limit) pass through ✅ End-to-end execution - Tool executes and returns results to agent

Code Structure

crewai_tool_kwargs/
├── __init__.py       # Module initialization
├── agent.py          # Agent with CrewAI tool
├── main.py           # Happy path test
└── README.md         # This file

Key Files

agent.py:

• Defines CustomSearchTool (CrewAI BaseTool with **kwargs)
• Wraps it with CrewaiTool
• Creates agent with the wrapped tool

main.py:

• Test 1: Basic search (no extra params)
• Test 2: Search with filters (tests **kwargs)

How It Works

1. CrewAI Tool Definition (agent.py):

   class CustomSearchTool(BaseTool):
       def _run(self, query: str, **kwargs) -> str:
           # kwargs receives: category, date_range, limit, etc.
   

2. ADK Wrapping (agent.py):

   adk_search_tool = CrewaiTool(
       crewai_search_tool,
       name="search_with_filters",
       description="..."
   )
   

3. LLM Function Calling (main.py):

   • LLM sees the tool in function calling format
   • LLM calls with: {query: "...", category: "...", date_range: "...", limit: 10}
   • CrewaiTool passes ALL parameters to **kwargs

4. Tool Execution:

   • query → positional parameter
   • category, date_range, limit → collected in **kwargs
   • Tool logic uses all parameters

Troubleshooting

ImportError: No module named 'crewai'

pip install 'crewai-tools>=0.2.0'

Python Version Error

CrewAI requires Python 3.10+:

python --version  # Should be 3.10 or higher

Missing API Key

export GOOGLE_API_KEY="your-key-here"

Related

• Parent class: FunctionTool - Base class for all function-based tools
• Unit tests: tests/unittests/tools/test_crewai_tool.py