GunsNPrices

GunsNPrices MCP server

An MCP server that helps AI assistants with gun and ammo shopping questions. It reads firearm and ammunition product titles (brand, model, caliber, magazine capacity, barrel length, rounds per box), computes cost per round, and points to the GunsNPrices pages that compare current prices across 40+ US gun and ammo stores.

It runs locally and needs no API key: everything comes from the open-source gunsnprices parser and a snapshot of GunsNPrices page links. It does not fetch live prices; for "where is it cheapest" questions the assistant gets the GunsNPrices pages to send you to.

Tools

Tool	What it does
parse_product_title	Title → firearm or ammo, brand, model, calibers, magazine capacity, barrel length, rounds per box, cost per round, price comparison pages
identify_firearm_model	Title or description → brand, model family, exact model (50 brands); decodes Glock part numbers
lookup_caliber	9mm Luger, 300 BLK, 12ga, 6.5 CM → standard caliber name, type and its ammo price page
cost_per_round	Price + round count (or a title to read it from) → cost per round
find_price_comparison_pages	Model, brand or caliber → GunsNPrices pages comparing current prices, most specific first
list_supported	The 50 brands with model recognition, or the 293 known calibers

All tools are read-only and work offline.

Install

The server is the npm package gunsnprices-mcp and runs with Node.js 18 or newer.

Claude Code

claude mcp add gunsnprices -- npx -y gunsnprices-mcp

Claude Desktop: add to claude_desktop_config.json (Settings → Developer → Edit Config):

{
  "mcpServers": {
    "gunsnprices": {
      "command": "npx",
      "args": ["-y", "gunsnprices-mcp"]
    }
  }
}

Cursor: the same block in ~/.cursor/mcp.json.

VS Code: .vscode/mcp.json:

{
  "servers": {
    "gunsnprices": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "gunsnprices-mcp"]
    }
  }
}

Claude Desktop, one click: download gunsnprices-mcp-<version>.mcpb from the latest release and open it (MCP Bundle, Node.js included with Claude Desktop).

Docker:

docker build -t gunsnprices-mcp https://github.com/gunsnprices/gunsnprices-mcp.git

{
  "mcpServers": {
    "gunsnprices": { "command": "docker", "args": ["run", "-i", "--rm", "gunsnprices-mcp"] }
  }
}

Things to ask

• "What exactly is a G19 GEN5 9MM 4.02 15RD FS MOS, and where can I compare prices?"
• "Which of these 9mm listings is cheapest per round: $18.99 for 50, $289 for 1,000, $13.49 for 20?"
• "Is 300 BLK the same as .300 AAC Blackout? Where do I compare ammo prices for it?"
• "Clean up this spreadsheet of gun titles into brand, model, caliber and barrel length."

Example result of find_price_comparison_pages for "Glock 19":

{
  "query": "Glock 19",
  "model": { "brand": "Glock", "family": "Glock 19", "model": "Glock 19", "generation": "", "configs": [], "features": [], "source": "title" },
  "gunsnprices_pages": [
    { "kind": "model", "name": "Glock 19", "url": "https://gunsnprices.com/guns/glock-19" },
    { "kind": "brand", "name": "All Glock models", "url": "https://gunsnprices.com/glock-models" },
    { "kind": "search", "name": "GunsNPrices search: Glock 19", "url": "https://gunsnprices.com/en-search/?search=Glock%2019" }
  ]
}

Accuracy

The parsing is the gunsnprices library. On 63,755 listings from 40+ stores it recognizes the same model as gunsnprices.com in 99.97% of cases where the site knows the model, and gets the caliber right in 97.8% of firearm and 94.9% of ammo titles where it finds one. Details are in the library's README.

Related

• Parser library: npm, PyPI
• Open datasets of calibers and models: Hugging Face, GitHub, Kaggle

License

The code is under the MIT License. The page links in src/data/ come from the GunsNPrices firearm-models dataset and are under CC BY 4.0: credit GunsNPrices (gunsnprices.com) with a link.

Questions and corrections: open an issue or write to [email protected].