structx-mcp 0.1.0

Model Context Protocol server for struct-x — install in Claude Desktop, Cursor, Windsurf, or any MCP-compatible client to give your agent structured-extraction superpowers.

structx-mcp

Model Context Protocol (MCP) server for struct-x — install in Claude Desktop, Cursor, Windsurf, or any MCP-compatible client and give your agent first-class structured-extraction tools.

You: extract the product details from this Aeron chair page →
     [pastes URL or HTML]
Agent: [calls structx_extract under the hood, returns typed JSON]
     {
       "title": "Aeron Chair",
       "price_cents": 179500,
       "brand": "Herman Miller",
       …
     }

No HTTP plumbing, no schema-writing detours — the agent just uses extraction.

Install

pip install structx-mcp

Then add to your MCP client's config.

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "structx": {
      "command": "structx-mcp",
      "env": {
        "STRUCTX_API_KEY": "sx_..."
      }
    }
  }
}

Restart Claude Desktop. Confirm by typing /mcp and verifying structx is listed.

Cursor

.cursor/mcp.json (project-scope) or ~/.cursor/mcp.json (user-scope):

{
  "mcpServers": {
    "structx": {
      "command": "structx-mcp",
      "env": { "STRUCTX_API_KEY": "sx_..." }
    }
  }
}

Windsurf / any other MCP client

Same pattern — command: "structx-mcp", env: { STRUCTX_API_KEY: ... }. The server speaks the standard MCP stdio protocol.

Tools the agent gets

Tool	What it does
structx_extract	Extract structured JSON from raw content (HTML / markdown / text / JSON / emails) using a JSON Schema you provide OR a pre-built template slug. Returns per-field confidence scores.
structx_infer_schema	Don't have a schema yet? Paste raw content, get a draft schema back with per-field rationales. Plus matching templates from the public catalog.
structx_extract_from_url	Fetch a URL and extract in one call. Sandboxed (HTTPS only, public DNS only, 10MB cap, no redirects). Replaces the two-call fetch_url → extract pattern.
structx_list_templates	Browse every public template — saves the agent from hand-writing a schema for common formats (Stripe events, GitHub issues, product pages, news articles).
structx_usage	Current credit usage for the API key. Pre-flight check before batches, or post-mortem after a RateLimitError.

Why use an MCP server vs. the SDK directly?

The Python SDK (structx-sdk) is for building applications. This MCP package is for putting struct-x inside the AI tools you already use — Claude Desktop, Cursor, Windsurf. The agent calls these tools natively, no app code required.

Both are first-party; they share the same backend, same credit pool, same API key.

Security

structx_extract_from_url is sandboxed at the network layer:

• HTTPS only (no http://, file://, ftp://, etc.)
• Hostname blocklist for cloud metadata targets (169.254.169.254, metadata.google.internal, etc.)
• Hostname suffix blocklist for internal-network conventions (.internal, .local, .cluster.local, .consul)
• DNS resolution + IP classification — refuses any private, loopback, link-local, multicast, or reserved IP
• No redirect following (one less SSRF vector)
• 10MB response cap

This matches the defenses on the struct-x backend's webhook outbound-URL validator. See src/structx_mcp/_url_safety.py for the implementation.

Development

git clone https://github.com/struct-x-ai/struct-x
cd struct-x/mcp/structx-mcp

# Install editable + the SDK from the local checkout (the SDK is in
# the same monorepo at sdk/python/).
pip install -e "../../sdk/python" -e ".[dev]"

pytest -q

License

MIT — see LICENSE.