@striderlabs/mcp-mercari

MCP (Model Context Protocol) server for automating Mercari resale marketplace operations using Playwright and Browserbase.

Overview

This server exposes Mercari functionality as MCP tools, enabling AI assistants to search listings, manage your selling inventory, view purchase/sales history, and create new listings.

Requirements

• Node.js >= 18
• A Browserbase account with CDP URL
• Mercari account (for authenticated operations)

Installation

npm install @striderlabs/mcp-mercari

Or from tarball:

npm install ./striderlabs-mcp-mercari-1.0.0.tgz

Configuration

Set the following environment variable:

export BROWSERBASE_CDP_URL="wss://connect.browserbase.com?apiKey=YOUR_KEY&sessionId=YOUR_SESSION"

Usage with Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "mercari": {
      "command": "npx",
      "args": ["@striderlabs/mcp-mercari"],
      "env": {
        "BROWSERBASE_CDP_URL": "wss://connect.browserbase.com?apiKey=YOUR_KEY&sessionId=YOUR_SESSION"
      }
    }
  }
}

Tools

search_listings

Search Mercari listings by keyword, category, and price range.

Parameters:

• keyword (required): Search term
• category (optional): Category filter (e.g. "Electronics", "Clothing")
• min_price (optional): Minimum price in USD
• max_price (optional): Maximum price in USD
• condition (optional): new | like_new | good | fair | poor
• limit (optional): Max results (default: 20)

Example:

{
  "keyword": "iPhone 14",
  "max_price": 600,
  "condition": "good",
  "limit": 10
}

get_listing_details

Get detailed information about a specific listing.

Parameters:

• listing_id (required): Mercari item ID or full URL

Example:

{
  "listing_id": "m12345678"
}

get_my_listings

Get listings you're currently selling (requires authentication).

Parameters:

• status (optional): on_sale | sold_out | all (default: on_sale)

create_listing

Create a new item listing on Mercari (requires authentication).

Parameters:

• title (required): Item title
• description (required): Item description
• price (required): Price in USD
• condition (required): new | like_new | good | fair | poor
• category (optional): Item category
• shipping_from (optional): State code (e.g. "CA")
• images (optional): Array of local file paths to item images

Example:

{
  "title": "Nike Air Max 90 Size 10",
  "description": "Worn twice, great condition. No box.",
  "price": 85,
  "condition": "like_new",
  "shipping_from": "CA",
  "images": ["/path/to/shoe-front.jpg", "/path/to/shoe-side.jpg"]
}

get_purchases

View your purchase history (requires authentication).

Parameters:

• limit (optional): Max items to return (default: 20)

get_sales

View your sales history (requires authentication).

Parameters:

• limit (optional): Max items to return (default: 20)

Authentication

Authenticated tools (get_my_listings, create_listing, get_purchases, get_sales) require an active Mercari session in the Browserbase browser. To authenticate:

1. Use Browserbase's live view to navigate to mercari.com and log in manually
2. The session cookies will persist for subsequent tool calls

How It Works

This server uses Playwright to control a browser via Browserbase's CDP endpoint. Each tool call:

1. Connects to the remote browser via CDP
2. Navigates to the relevant Mercari page
3. Extracts or fills in data using DOM selectors
4. Returns structured JSON results

License

MIT