> For the complete documentation index, see [llms.txt](https://docs.flowiseai.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flowiseai.com/integrations/llamaindex/tools/query-engine-tool.md).

# Query Engine Tool

Turns Query Engine into a Tool which can then be used by [Sub-Question Query Engine](/integrations/llamaindex/engine/sub-question-query-engine.md) or Agent.

<figure><img src="/files/huVYnQTXA64D1nyKeHvV" alt=""><figcaption></figcaption></figure>

## Inputs

* Vector Store Index

## Parameters

| Name             | Description                                         |
| ---------------- | --------------------------------------------------- |
| Tool Name        | Name of the tool                                    |
| Tool Description | A description to tell when LLM should use this tool |

## Outputs

| Name            | Description                                                                                                            |
| --------------- | ---------------------------------------------------------------------------------------------------------------------- |
| QueryEngineTool | Connecting point to Agent or [Sub-Question Query Engine](/integrations/llamaindex/engine/sub-question-query-engine.md) |