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.

webrain mcp

Logs go to stderr — never redirect stderr into the MCP stream. HTTP — for remote or streamable-http clients:

webrain mcp --http 9223   # endpoint: http://127.0.0.1:9223/mcp

Register it in a client

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

// Cursor — .mcp.json
{
  "mcpServers": {
    "webrain": { "command": "webrain", "args": ["mcp"] }
  }
}

// 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:

{
  "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 · Cursor · GitHub Copilot
Tools Reference — the 15 tools
Agent Decision Guide — which tool for which task

Getting Started

MCP Clients

Concepts

Guides

Comparisons

Reference

Project

MCP Server

MCP Server

Transports

Register it in a client

Verify it’s live

Client guides

​MCP Server

​Transports

​Register it in a client

​Verify it’s live

​Client guides

MCP Server

Transports

Register it in a client

Verify it’s live

Client guides