Koskamo

Username Inspector MCP

A free, public Model Context Protocol server that allows AI assistants to check username availability across 12 reselling platforms and compare seller fees. It provides tools to look up profile status, retrieve profile links, and calculate net profit after fees for US sellers, operating without requiring API keys or sign-ups.

Endpoint and access

No sign-in: your client connects and lists tools immediately, with no account or key.

Username Inspector MCP logo, by Username InspectorNo sign-inEndpoint checked 2026-10-18Operated by Username Inspector
MCP endpoint (Streamable HTTP)
https://usernameinspector.com/api/mcp
Vendor documentation

What you can do with it

  • Check if a specific username is available on platforms like eBay, Poshmark, and Vinted
  • Compare net profit and fees for a sale across multiple resale marketplaces
  • Retrieve public profile links for a username on 12 platforms without contacting marketplaces
Tools advertised by the last live check:
  • check_username
  • compare_fees

Connect from your client

Each snippet registers the same endpoint; pick the client you use.

This server is operated by the named third party. Listing and endpoint checks are not an endorsement or a security audit. Review the operator's permissions, terms, and data handling before connecting. How listings are checked and corrected.

Claude Code

Run this once in a terminal. It registers a Streamable HTTP server. Use --scope project to write .mcp.json for the repo.
Claude Code configuration
claude mcp add --transport http username-inspector-mcp https://usernameinspector.com/api/mcp

Codex

Run this once. Codex stores MCP servers in ~/.codex/config.toml (or .codex/config.toml in a trusted project).
Codex configuration
codex mcp add username-inspector-mcp --url https://usernameinspector.com/api/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable username-inspector-mcp in your MCP settings.
Cursor configuration
{
  "mcpServers": {
    "username-inspector-mcp": {
      "url": "https://usernameinspector.com/api/mcp"
    }
  }
}

Cline

Merge this into cline_mcp_settings.json (Cline → MCP Servers → Configure). The type must be streamableHttp for a remote HTTP server.
Cline configuration
{
  "mcpServers": {
    "username-inspector-mcp": {
      "type": "streamableHttp",
      "url": "https://usernameinspector.com/api/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start username-inspector-mcp and inspect its tools.
VS Code configuration
{
  "servers": {
    "username-inspector-mcp": {
      "type": "http",
      "url": "https://usernameinspector.com/api/mcp"
    }
  }
}

Gemini CLI

Run this once. It writes .gemini/settings.json in the current project; pass --scope user for ~/.gemini/settings.json.
Gemini CLI configuration
gemini mcp add --transport http username-inspector-mcp https://usernameinspector.com/api/mcp

Claude Desktop

Merge this into claude_desktop_config.json (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\), then restart Claude Desktop.
Claude Desktop configuration
{
  "mcpServers": {
    "username-inspector-mcp": {
      "url": "https://usernameinspector.com/api/mcp"
    }
  }
}

Windsurf

Merge this into ~/.codeium/windsurf/mcp_config.json, then refresh MCP in Cascade. Windsurf remote servers use serverUrl, not url.
Windsurf configuration
{
  "mcpServers": {
    "username-inspector-mcp": {
      "serverUrl": "https://usernameinspector.com/api/mcp"
    }
  }
}

Do you run Username Inspector MCP?

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