vaquill-mcp

MCP server for Vaquill legal research API. Covers US federal and 50-state primary law: USC, CFR, state statutes and regulations, state and US constitutions, court rules, the Federal Register, executive orders, and agency guidance. Search primary law, resolve statutory citations, browse the hierarchy, and ground answers in official sources, all from your AI tools.

Quick Start

Prerequisites

Sign up at vaquill.ai to get your API key.

Claude.ai (Web)

No installation needed. Add as a remote MCP server in Claude.ai Settings > Integrations:

Option A: Simple URL (API key in path)

https://mcp.vaquill.ai/s/vq_key_your_key_here

Option B: Bearer token (recommended)

URL:   https://mcp.vaquill.ai/s/_
Token: vq_key_your_key_here

Available on Claude Pro, Max, Team, and Enterprise plans.

Claude Desktop

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

{
  "mcpServers": {
    "vaquill": {
      "command": "uvx",
      "args": ["vaquill-mcp"],
      "env": {
        "VAQUILL_API_KEY": "vq_key_your_key_here"
      }
    }
  }
}

Claude Code

Remote (no install):

claude mcp add-json vaquill '{"type":"http","url":"https://mcp.vaquill.ai/s/_","headers":{"Authorization":"Bearer vq_key_your_key_here"}}'

Local (via uvx):

claude mcp add vaquill -- uvx vaquill-mcp
# Then set the env var in your shell: export VAQUILL_API_KEY=vq_key_...

Or add to .claude/settings.json:

{
  "mcpServers": {
    "vaquill": {
      "command": "uvx",
      "args": ["vaquill-mcp"],
      "env": {
        "VAQUILL_API_KEY": "vq_key_your_key_here"
      }
    }
  }
}

Cursor

Add to Cursor Settings > MCP Servers:

{
  "mcpServers": {
    "vaquill": {
      "command": "uvx",
      "args": ["vaquill-mcp"],
      "env": {
        "VAQUILL_API_KEY": "vq_key_your_key_here"
      }
    }
  }
}

VS Code (Copilot)

Add to .vscode/settings.json:

{
  "mcp": {
    "servers": {
      "vaquill": {
        "command": "uvx",
        "args": ["vaquill-mcp"],
        "env": {
          "VAQUILL_API_KEY": "vq_key_your_key_here"
        }
      }
    }
  }
}

Windsurf

Add to ~/.windsurf/settings.json:

{
  "mcpServers": {
    "vaquill": {
      "command": "uvx",
      "args": ["vaquill-mcp"],
      "env": {
        "VAQUILL_API_KEY": "vq_key_your_key_here"
      }
    }
  }
}

Available Tools

Tools are generated from the live Vaquill API's OpenAPI spec at startup, so the set always matches the current API. For the authoritative, up-to-date list and per-call credit costs, run the free get_pricing tool or inspect your MCP client's tool list. The main groups (representative tools shown):

US statutes & regulations

USC, CFR, all 50 state codes, constitutions, state court rules, the Federal Register, and agency guidance.

Tool	Description
search_us_statutes	Hybrid semantic + keyword search; filter by corpusType, state, titleNumber, chapter, year, and more.
get_us_statute_section	Section metadata by actId (citation, hierarchy, official-source links).
get_us_statute_section_text	Full HTML + plain text of a section.
resolve_statute_citation	Resolve a Bluebook citation (e.g. 42 U.S.C. § 1983) straight to its section.
list_statute_divisions	Browse the statutory hierarchy one level at a time.
list_statutes_coverage	Self-describing coverage matrix: which corpora exist in which jurisdiction.

Utility

Tool	Description
get_pricing	Live API credit pricing (free, no auth).

Environment Variables

Variable	Required	Default	Description
VAQUILL_API_KEY	Yes	-	API key (vq_key_...) from vaquill.ai
VAQUILL_BASE_URL	No	https://api.vaquill.ai	API base URL
VAQUILL_TIMEOUT	No	120	Request timeout in seconds

Example Usage

Once configured, you can ask your AI assistant things like:

• "What does 17 CFR 240.10b-5 say about insider trading?"
• "Resolve 42 U.S.C. § 1983 to its section and show the full text"
• "Find California statutes on tenant repair obligations"
• "Browse the Texas statutory codes, then drill into the Penal Code"

Development

# Clone and install
git clone https://github.com/Vaquill-AI/vaquill-mcp.git
cd vaquill-mcp
uv sync --all-extras

# Run locally
VAQUILL_API_KEY=vq_key_... uv run vaquill-mcp

# Run tests
uv run pytest

# Test with FastMCP inspector
uv run fastmcp dev src/vaquill_mcp/server.py

How It Works

This package is a thin MCP wrapper around the Vaquill Developer API. At startup, it fetches the OpenAPI spec from the live API and auto-generates MCP tools using FastMCP. Tool names are derived automatically from each endpoint's OpenAPI operation id, so new API endpoints show up as clean, ready-to-use tools with no package update; key descriptions are refined for optimal LLM performance.

Because the spec is fetched at startup (not bundled), tools automatically reflect any API changes without a package update.

Credits & Pricing

API calls consume credits. The credit costs in the tables above are current at the time of writing; the get_pricing tool and each tool's own description always reflect the live price, so treat those as authoritative if they differ.

1 credit = $0.01 USD

License

MIT