crewAI/docs/tools/llamaindex-tool.mdx

---
title: LlamaIndexTool
description: A wrapper tool for integrating LlamaIndex tools and query engines with CrewAI
icon: link
---

## LlamaIndexTool

The LlamaIndexTool serves as a bridge between CrewAI and LlamaIndex, allowing you to use LlamaIndex tools and query engines within your CrewAI agents. It supports both direct tool wrapping and query engine integration.

## Installation

```bash
pip install 'crewai[tools]'
pip install llama-index  # Required for LlamaIndex integration
```

## Usage Examples

### Using with LlamaIndex Tools

```python
from crewai import Agent
from crewai_tools import LlamaIndexTool
from llama_index.core.tools import BaseTool as LlamaBaseTool
from pydantic import BaseModel, Field

# Create a LlamaIndex tool
class CustomLlamaSchema(BaseModel):
    query: str = Field(..., description="Query to process")

class CustomLlamaTool(LlamaBaseTool):
    name = "Custom Llama Tool"
    description = "A custom LlamaIndex tool"
    
    def __call__(self, query: str) -> str:
        return f"Processed: {query}"

# Wrap the LlamaIndex tool
llama_tool = CustomLlamaTool()
wrapped_tool = LlamaIndexTool.from_tool(llama_tool)

# Create an agent with the tool
agent = Agent(
    role='LlamaIndex Integration Agent',
    goal='Process queries using LlamaIndex tools',
    backstory='Specialist in integrating LlamaIndex capabilities.',
    tools=[wrapped_tool]
)
```

### Using with Query Engines

```python
from crewai import Agent
from crewai_tools import LlamaIndexTool
from llama_index.core import VectorStoreIndex, Document

# Create a query engine
documents = [Document(text="Sample document content")]
index = VectorStoreIndex.from_documents(documents)
query_engine = index.as_query_engine()

# Create the tool
query_tool = LlamaIndexTool.from_query_engine(
    query_engine,
    name="Document Search",
    description="Search through indexed documents"
)

# Create an agent with the tool
agent = Agent(
    role='Document Researcher',
    goal='Find relevant information in documents',
    backstory='Expert at searching through document collections.',
    tools=[query_tool]
)
```

## Tool Creation Methods

### From LlamaIndex Tool

```python
@classmethod
def from_tool(cls, tool: Any, **kwargs: Any) -> "LlamaIndexTool":
    """
    Create a CrewAI tool from a LlamaIndex tool.

    Args:
        tool (LlamaBaseTool): A LlamaIndex tool to wrap
        **kwargs: Additional arguments for tool creation

    Returns:
        LlamaIndexTool: A CrewAI-compatible tool wrapper

    Raises:
        ValueError: If tool is not a LlamaBaseTool or lacks fn_schema
    """
```

### From Query Engine

```python
@classmethod
def from_query_engine(
    cls,
    query_engine: Any,
    name: Optional[str] = None,
    description: Optional[str] = None,
    return_direct: bool = False,
    **kwargs: Any
) -> "LlamaIndexTool":
    """
    Create a CrewAI tool from a LlamaIndex query engine.

    Args:
        query_engine (BaseQueryEngine): The query engine to wrap
        name (Optional[str]): Custom name for the tool
        description (Optional[str]): Custom description
        return_direct (bool): Whether to return query engine response directly
        **kwargs: Additional arguments for tool creation

    Returns:
        LlamaIndexTool: A CrewAI-compatible tool wrapper

    Raises:
        ValueError: If query_engine is not a BaseQueryEngine
    """
```

## Integration Example

```python
from crewai import Agent, Task, Crew
from crewai_tools import LlamaIndexTool
from llama_index.core import VectorStoreIndex, Document
from llama_index.core.tools import QueryEngineTool

# Create documents and index
documents = [
    Document(text="AI is a technology that simulates human intelligence."),
    Document(text="Machine learning is a subset of AI.")
]
index = VectorStoreIndex.from_documents(documents)
query_engine = index.as_query_engine()

# Create the tool
search_tool = LlamaIndexTool.from_query_engine(
    query_engine,
    name="AI Knowledge Base",
    description="Search through AI-related documents"
)

# Create agent
researcher = Agent(
    role='AI Researcher',
    goal='Research AI concepts',
    backstory='Expert at finding and explaining AI concepts.',
    tools=[search_tool]
)

# Define task
research_task = Task(
    description="""Find and explain what AI is and its relationship  
    with machine learning.""",
    agent=researcher
)

# The agent will use:
# {
#   "query": "What is AI and how does it relate to machine learning?"
# }

# Create crew
crew = Crew(
    agents=[researcher],
    tasks=[research_task]
)

# Execute
result = crew.kickoff()
```

## Notes

- Automatically adapts LlamaIndex tool schemas for CrewAI compatibility
- Renames 'input' parameter to 'query' for better integration
- Supports both direct tool wrapping and query engine integration
- Handles schema validation and error resolution
- Thread-safe operations
- Compatible with all LlamaIndex tool types and query engines