> ## Documentation Index
> Fetch the complete documentation index at: https://docs.caylex.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Needle

> Semantic search and document management for AI

The Needle MCP Server brings powerful semantic search and document management capabilities to AI agents within your Caylex projects, enabling them to retrieve relevant information from files such as PDFs, DOCX, and XLSX with context-aware precision. Built on the Model Context Protocol, Needle acts as a bridge between your AI agents and document collections (called 'collections' in Needle), allowing agents to perform RAG (Retrieval-Augmented Generation) workflows and maintain long-term memory over large document sets. Once connected in Caylex, your agents can search across uploaded documents, manage collections, and surface buried knowledge instantly — without manual file parsing. Authentication is handled via a Needle API key passed as a Bearer token in the Authorization header, which you configure when adding the server to your Caylex project.

<Warning>
  **Prerequisites:**

  * A Needle account is required — obtain your API key from the Needle Settings page at needle.app/dashboard/settings.
  * Documents must be uploaded to Needle collections before agents can search or retrieve them through the MCP server.
</Warning>

<Note>
  **Important API details:**

  * Authentication requires a valid Needle API key sent as a Bearer token in the Authorization request header.
  * The server supports both SSE and Streamable HTTP transport; the Streamable HTTP endpoint is recommended as SSE has been deprecated in the latest MCP specification.
  * Pagination behavior is supported by the server according to the repository changelog, so large document collections may return results in pages.
</Note>

## Server Details

| Property        | Value                                                    |
| --------------- | -------------------------------------------------------- |
| **Transport**   | Streamable HTTP                                          |
| **Server Type** | External                                                 |
| **Endpoint**    | [https://mcp.needle.app/mcp](https://mcp.needle.app/mcp) |
| **Categories**  | Memory & Knowledge, AI & Machine Learning                |

## Authentication

This server supports the following authentication method:

### Header Authentication

This server authenticates via HTTP headers. During the server onboarding flow, you will be prompted to confirm the required headers. Note that you do not provide the values for the headers during the server on-boarding.
Header values are provided by the users during the [Auth Link](/auth/auth-links) flow.

## Getting Started

<Steps>
  <Step title="Add the server">
    Navigate to the **Server Library** and click on the **New Server** button. Find **Needle** in the Caylex Catalog.
  </Step>

  <Step title="Server Onboarding flow">
    Go through the server onboarding flow.
  </Step>

  <Step title="Use in a project">
    Add the server to a [project](https://app.caylex.dev/projects) by configuring project connections. Its tools are now available to any agents connected to that project.
  </Step>
</Steps>

## Related Servers

<CardGroup cols={2}>
  <Card title="Notion" href="/server-catalog/notion" icon="https://d338mlbnszozgc.cloudfront.net/logos/notion.svg" />

  <Card title="Google Drive" href="/server-catalog/google-drive" icon="https://d338mlbnszozgc.cloudfront.net/logos/google-drive.svg" />
</CardGroup>

## References

<CardGroup cols={1}>
  <Card title="https://docs.needle-ai.com/docs/guides/mcp/needle-mcp-server/" href="https://docs.needle-ai.com/docs/guides/mcp/needle-mcp-server/" icon="arrow-up-right-from-square" />

  <Card title="https://docs.needle-ai.com/docs/mcp/" href="https://docs.needle-ai.com/docs/mcp/" icon="arrow-up-right-from-square" />

  <Card title="https://github.com/needle-ai/needle-mcp" href="https://github.com/needle-ai/needle-mcp" icon="arrow-up-right-from-square" />
</CardGroup>