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

# MCP Server

> Run webrain as a Model Context Protocol server — stdio or HTTP transport, JSON-RPC on stdout, and the exact configuration for any MCP client.

# MCP Server

webrain is a **Model Context Protocol (MCP) server**. Start it and any
MCP-capable client (Claude, Claude Code, Cursor, GitHub Copilot, Codex, …)
discovers its **15 tools** automatically — no wrappers, no daemon.

## Transports

**stdio** — the default; the client spawns `webrain mcp` and speaks JSON-RPC on
stdout.

```bash theme={null}
webrain mcp
```

Logs go to **stderr** — never redirect stderr into the MCP stream.

**HTTP** — for remote or streamable-http clients:

```bash theme={null}
webrain mcp --http 9223   # endpoint: http://127.0.0.1:9223/mcp
```

## Register it in a client

```jsonc theme={null}
// VS Code (GitHub Copilot) — .vscode/mcp.json
{
  "servers": {
    "webrain": {
      "type": "stdio",
      "command": "webrain",
      "args": ["mcp"]
    }
  }
}
```

```jsonc theme={null}
// Cursor — .mcp.json
{
  "mcpServers": {
    "webrain": { "command": "webrain", "args": ["mcp"] }
  }
}
```

```json theme={null}
// Claude Desktop — claude_desktop_config.json
{
  "mcpServers": {
    "webrain": { "command": "webrain", "args": ["mcp"] }
  }
}
```

Point `CDP_URL` at a running engine to reuse an already-open browser:

```jsonc theme={null}
{
  "servers": {
    "webrain": {
      "type": "stdio",
      "command": "webrain",
      "args": ["mcp"],
      "env": { "CDP_URL": "http://127.0.0.1:9222" }
    }
  }
}
```

## Verify it's live

Ask the LLM to call `webrain_guide` — it returns the browser / challenge /
extraction decision guide. Then try:

> Scrape all product titles + prices from URL X

The model calls `webrain_navigate` → `webrain_extract` (mode=autoschema) →
`webrain_extract` (mode=schema).

## Client guides

* [Claude](/mcp/claude) · [Cursor](/mcp/cursor) · [GitHub Copilot](/mcp/copilot)
* [Tools Reference](/reference/tools) — the 15 tools
* [Agent Decision Guide](/guides/agent-decision-guide) — which tool for which task