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

# What is the Model Context Protocol (MCP)?

> A look at Anthropic's MCP standard and how Bridger fits into it.

The **Model Context Protocol (MCP)** is an open protocol released by Anthropic for AI models to access
external tools, data, and systems in a standardized way. It's based on JSON-RPC 2.0 and uses STDIO or
HTTP + SSE transports.

## Core concepts

<CardGroup cols={2}>
  <Card title="Server" icon="server">
    A process that exposes tools (`tools`), resources (`resources`), and prompts (`prompts`).
  </Card>

  <Card title="Client" icon="plug">
    Claude Desktop, Cursor, custom agents — attach to a Server and call tools.
  </Card>

  <Card title="Tool" icon="wrench">
    A callable function with a name, description, and input schema (JSON Schema).
  </Card>

  <Card title="Transport" icon="route">
    Two standard transports: STDIO (local process) or Streamable HTTP (remote).
  </Card>
</CardGroup>

## Standard methods

The MCP methods the Bridger Gateway currently handles are as follows.

| Method                             | Purpose                                                        | Bridger                       |
| ---------------------------------- | -------------------------------------------------------------- | ----------------------------- |
| `initialize`                       | Handshake — exchange protocol version and capabilities         | Supported                     |
| `notifications/initialized`        | Initialization-complete notification                           | Supported                     |
| `tools/list`                       | Retrieve metadata of exposed tools                             | Supported                     |
| `tools/call`                       | Run a tool — takes `name` + `arguments` and returns the result | Supported                     |
| `resources/list`, `resources/read` | Query static/dynamic resources                                 | Not supported (tools-focused) |
| `prompts/list`, `prompts/get`      | Predefined prompt templates                                    | Not supported (tools-focused) |

<Note>
  Bridger is a **tools-focused** gateway. `resources/*` and `prompts/*` are standard MCP methods
  but are not handled by the Gateway today; any other method responds with `Method not found`.
</Note>

## Bridger and MCP

Bridger is an **MCP Server hosting platform**. Without writing, deploying, or operating your own
MCP server, any OpenAPI spec is instantly converted into MCP tools.

```text theme={null}
OpenAPI spec (preset YAML or BYOAPI registration)
        │
        ▼
  ┌─────────────────────────────┐
  │  Bridger Gateway              │
  │  (mcp.datari.kr/mcp)        │
  ├─────────────────────────────┤
  │  • tools/list                │
  │  • tools/call                │
  │  • SSE event stream          │
  └─────────────────────────────┘
        │
        ▼
   Claude / Cursor / custom agents
```

* A single domain (`mcp.datari.kr`) multiplexes **hundreds of tools** by name (`getultrashortcast`,
  `getapttrade`...). Official preset servers are distinguished by `{category}/{name}` IDs, while BYOAPI
  tools use the `@{owner}/{slug}` namespace.
* Use all registered tools with **a single API Key** — no need to spin up a separate Server.
* Clients work as-is with any MCP-compatible client (Claude Desktop, Cursor, a ChatGPT Actions adapter, your own SDK).

## Next steps

<CardGroup cols={2}>
  <Card title="View the architecture" icon="diagram-project" href="/en/concepts/architecture">
    How the Gateway, Registry, and middleware fit together.
  </Card>

  <Card title="Call your first tool" icon="play" href="/en/getting-started/first-tool">
    Run a real JSON-RPC call yourself.
  </Card>
</CardGroup>