@retailerapi/mcp

Model Context Protocol server for retailerapi.com — a unified product-data API covering major US retailers. Two tools your AI agent can call directly: product lookups and live offers.

Works with Claude Desktop, Claude Code, Cursor, and any other MCP-compatible client over stdio.

Covered retailers: Walmart, Amazon, eBay, Target, Best Buy, Lowe’s, Home Depot. Set include_cross_retailer=true on a product lookup to surface cached cells for every retailer we have for that UPC.

Quick start

1. Get an API key

Sign in at app.retailerapi.com and create a key on the API Keys page. Keys look like rk_live_…. Free tier is 1,000 lookups/month — no card.

2. Add the server to your MCP client

Claude Desktop

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

{
  "mcpServers": {
    "retailerapi": {
      "command": "npx",
      "args": ["-y", "@retailerapi/mcp"],
      "env": {
        "RETAILERAPI_KEY": "rk_live_your_key_here"
      }
    }
  }
}

Restart Claude Desktop. The retailerapi tools will appear in the tool picker.

Claude Code

claude mcp add retailerapi npx -y @retailerapi/mcp \
  --env RETAILERAPI_KEY=rk_live_your_key_here

Cursor

Add to ~/.cursor/mcp.json (or the project-level .cursor/mcp.json):

{
  "mcpServers": {
    "retailerapi": {
      "command": "npx",
      "args": ["-y", "@retailerapi/mcp"],
      "env": {
        "RETAILERAPI_KEY": "rk_live_your_key_here"
      }
    }
  }
}

Generic stdio

RETAILERAPI_KEY=rk_live_your_key_here npx @retailerapi/mcp

The process speaks MCP over stdio (newline-delimited JSON-RPC on stdin/stdout). Logs go to stderr.

Tools

lookup_product

Resolve any identifier (UPC / EAN / ISBN / GTIN / Amazon ASIN / retailer item_id) into a normalized product summary. Base call (1 token) returns: title, brand, image, current price, identifiers, weight, dimensions, MSRP, description, categories, full price history, aggregated stats, retailer_links (free ‘where to find it’), Bucket-1 facts (sold_tag, estimated_sales, is_best_seller, pack_count, hazmat), and computed marketplace fees (referral_fee_usd, wfs_fee_usd). Fees are FREE in base call — Keepa parity.

Set include_cross_retailer=true to add the cross_retailer block — a map keyed by retailer slug of cached per-retailer cells (price, in_stock, Bucket-1 fields) for every retailer we have for this UPC (+2 tokens). Read-only over our cache. Set include_seller_context=true to add live seller-side state (is_restricted, WFS eligibility) on marketplace retailers (+3 tokens).