Secondhand MCP

A Model Context Protocol (MCP) server that lets AI assistants search secondhand marketplaces. Search Facebook Marketplace, eBay, Depop, and Poshmark for used and secondhand items — filter by price, category, condition, size, and color, then get full listing details with photos, descriptions, and seller info.

Works with Claude Desktop, Claude Code, Cursor, and other clients that run MCP servers locally.

[!TIP] Using ChatGPT? This one won't work there.

It runs on your computer, so it only works where your computer is — Claude Desktop, Claude Code, Cursor. Secondhand MCP Cloud is the same search, always on, so whichever assistant you actually use can reach it. Free tier, no card.

	This repo	Cloud
Claude Desktop, Code, Cursor	✅	✅
ChatGPT, Claude, and other assistants	—	✅
Searching from your phone	—	✅
Chrome running in the background	needed	not needed
Price	free, forever	free tier, then $4.99

Supported Marketplaces

Marketplace	Auth Required	Notes
Facebook Marketplace	No	Location-based search
eBay	Yes (API keys)	Official Browse API
Depop	No	Requires Chrome installed
Poshmark	No	Requires Chrome installed

Setup

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "secondhand": {
      "command": "npx",
      "args": ["-y", "secondhand-mcp"],
      "env": {
        "EBAY_CLIENT_ID": "your-ebay-client-id",
        "EBAY_CLIENT_SECRET": "your-ebay-client-secret",
        "EBAY_MARKETPLACE_ID": "EBAY_US"
      }
    }
  }
}

Claude Code

Add to ~/.claude/.mcp.json:

{
  "mcpServers": {
    "secondhand": {
      "command": "npx",
      "args": ["-y", "secondhand-mcp"],
      "env": {
        "EBAY_CLIENT_ID": "your-ebay-client-id",
        "EBAY_CLIENT_SECRET": "your-ebay-client-secret",
        "EBAY_MARKETPLACE_ID": "EBAY_US"
      }
    }
  }
}

eBay, Depop, and Poshmark are all optional — if eBay API keys are missing or Chrome isn't installed, those marketplaces are automatically disabled and the rest still work.

Depop & Poshmark / Chrome Requirement

Depop and Poshmark require a headless browser. If Google Chrome or Chromium is installed on your system, both are automatically enabled — no config needed. If Chrome isn't found, they are silently skipped.

On macOS, the first time you search Depop or Poshmark, you may see a system prompt asking to allow Node.js to control Chrome. This is expected — puppeteer needs to launch Chrome in headless mode. Allow it once and it won't ask again.

The browser runs invisibly in the background and only launches when you actually search Depop or Poshmark.

Configuration

Choosing Marketplaces

By default all marketplaces are enabled. To limit which are active, set the MARKETPLACES env var (comma-separated):

{
  "env": {
    "MARKETPLACES": "facebook,ebay"
  }
}

Valid values: facebook, ebay, depop, poshmark

eBay API Keys

eBay uses the official Browse API. You need a free eBay developer account:

1. Create an account at developer.ebay.com
2. Create an application to get a Client ID and Client Secret
3. Add them to your MCP config as EBAY_CLIENT_ID and EBAY_CLIENT_SECRET

eBay Marketplace / Region

By default the server targets the US eBay site. To search a different regional marketplace, set the EBAY_MARKETPLACE_ID environment variable:

{
  "env": {
    "EBAY_MARKETPLACE_ID": "EBAY_DE"
  }
}

Common values:

Value	Site
EBAY_US	ebay.com (default)
EBAY_DE	ebay.de
EBAY_GB	ebay.co.uk
EBAY_AU	ebay.com.au
EBAY_FR	ebay.fr
EBAY_IT	ebay.it
EBAY_ES	ebay.es
EBAY_CA	ebay.ca

The full list is available in the eBay API docs.

Tools

search_marketplace

Search for items across marketplaces.

Parameter	Required	Default	Description
query	Yes		Search terms
marketplace	No	facebook	facebook, ebay, depop, poshmark, or all
location	No	san francisco	City to search in (Facebook only)
radiusMiles	No	25	Search radius in miles, up to 500 (Facebook only)
maxPrice	No		Maximum price
minPrice	No		Minimum price
limit	No	20	Max results
showSold	No	false	Include sold items (Facebook only)
includeImages	No	false	Include image URLs in output
sort	No	relevance	Sort order (Depop, Poshmark): relevance, newest, most_popular, price_low_to_high, price_high_to_low
condition	No		Item condition. eBay: new, like_new, good, fair. Depop: new, like_new, excellent, good, fair, used. Poshmark: new (NWT), like_new (NWOT), good, fair
category	No		Product category. Depop: tops, bottoms, dresses, coats-jackets, footwear, accessories, bags, jewellery, activewear, swimwear. Poshmark: Jackets_&_Coats, Dresses, Shoes, Accessories, etc.
brand	No		Brand filter (Poshmark only): e.g. "Nike", "Levi's", "Gucci"
department	No		Department filter (Poshmark only): Women, Men, Kids
sizes	No		Size filter (Depop, Poshmark): e.g. ["S", "M", "L"] or ["US 9", "US 10"]
colors	No		Color filter (Depop, Poshmark): black, white, red, blue, green, yellow, orange, pink, purple, brown, grey, cream, multi, silver, gold

Data returned per marketplace:

Field	Facebook	eBay	Depop	Poshmark
Title	Yes	Yes	Yes	Yes
Price	Yes	Yes	Yes	Yes
Location	City	City, State	—	—
Condition	—	Yes	—	—
Photo count	1 thumbnail	1 thumbnail	1 thumbnail	1 thumbnail
Seller	Yes	Yes	—	—

get_listing_details

Get full details for a specific listing using an ID from search results.

Parameter	Required	Default	Description
listingId	Yes		Listing ID from search results
marketplace	No	facebook	facebook, ebay, depop, or poshmark

Data returned per marketplace:

Field	Facebook	eBay	Depop	Poshmark
Description	Yes	Yes	Yes	Yes
All photos	Yes	Yes	Yes	Yes
Location	City	City, State, Country	—	—
Seller	Name	Username	Username	Username
Delivery types	Yes	—	—	—
Shipping	Yes/No	Service codes	Yes/No	Always included

list_marketplaces

List all enabled marketplaces and their status.

search / fetch (deep research)

Convenience pair following the ChatGPT Deep Research tool contract — exact names, a single string argument each:

• search(query) — searches every enabled marketplace at once and returns { results: [{ id, title, text, url }] }, where id is marketplace:listingId
• fetch(id) — returns full listing details for a search result ID as { id, title, text, url, metadata }

Useful for research-style clients that expect these standard tool names; for filtered searches use search_marketplace.

How It Works

Facebook Marketplace — Searches listings by location, radius, price, and query. Resolves city names to coordinates. No login or browser needed. Facebook serves non-browser callers a gated version of its search API from time to time (a single result with more pages behind it, or stubs with no listing inside); when that happens the server reads the logged-out search page instead, which still carries a full first page of results.

eBay — Uses the official eBay Browse API with OAuth 2.0 client credentials. Tokens are cached and auto-refreshed. The target regional marketplace is controlled by EBAY_MARKETPLACE_ID (default: EBAY_US).

Depop — Uses a headless browser to search listings with support for category, condition, size, and color filters. The browser instance is shared across requests.

Poshmark — Uses a headless browser to search listings with support for condition, size, color, sort, and price filters. Poshmark is not location-based — all items ship nationally.

Development

git clone https://github.com/jlsookiki/secondhand-mcp.git
cd secondhand-mcp
npm install
npm run build

Adding a Marketplace

1. Create a new file in src/marketplaces/
2. Extend BaseMarketplace and implement search() and optionally getListingDetails()
3. Add the constructor to allMarketplaces in src/marketplaces/index.ts

Limitations

• Facebook: May break if Facebook changes their frontend
• eBay: Requires developer API keys (free tier available)
• Depop: Requires Chrome/Chromium installed; slower than Facebook/eBay (~5s per search)
• Poshmark: Requires Chrome/Chromium installed; no official API so relies on page scraping
• Rate limiting: Don't make too many requests too quickly

License

MIT