Connect Secondhand MCP to Claude

One custom connector, about 30 seconds, and every Claude chat can search Facebook Marketplace, eBay, Depop, and Poshmark.

Claude.ai supports remote MCP connectors natively — no install, no browser extension, no API keys. You add the connector once from a desktop browser; after that it works everywhere you use Claude, including the mobile app. The free tier needs no credit card.

Setup steps

Takes about two minutes, once

  1. Open Claude settings

    On claude.ai (desktop browser), click your initials → SettingsConnectors.

  2. Add a custom connector

    Click Add custom connector at the bottom of the connectors list.

  3. Paste the connector URL

    Enter https://secondhandmcp.com/mcp and click Add.

  4. Sign in

    Claude opens a sign-in window — use an email magic link or Google. This creates your free account (10 searches/month, no card).

  5. Start searching

    In any chat, ask something like "Find a mid-century coffee table under $200 near San Francisco." Claude will call Secondhand MCP and return real listings.

Frequently asked questions

Does this work on the Claude mobile app?

Yes. Add the connector once from a desktop browser; after that it works in Claude everywhere, including iOS and Android apps.

Do I need a paid Claude plan?

Custom connectors are available on Claude paid plans. Secondhand MCP itself has a free tier — 10 searches a month, no credit card.

Which marketplaces work on the free tier?

Facebook Marketplace works immediately. eBay works with your own free API keys. Depop and Poshmark are on Pro ($5/mo).

Is it safe?

The server is read-only — it can search and fetch listings, never post, message, or buy. Authentication is OAuth 2.1; you can disconnect it from Claude settings at any time.

What you can search