Koskamo

B20 Check MCP MCP server

This MCP server enables AI agents to verify B20 tokens on the Base blockchain by checking issuer powers, detecting imposter tokens, and retrieving signed EIP-712 verdicts. It supports both a free rate-limited demo route and a paid x402 endpoint for unmetered access, allowing agents to assess token safety without trusting the API blindly.

Endpoint and access

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

No sign-inEndpoint checked 2026-10-05Operated by B20 Check
MCP endpoint (Streamable HTTP)
https://b20check.com/mcp
Vendor documentation

What you can do with it

  • Verify if a B20 token on Base has active issuer backdoors
  • Detect imposter tokens using signed EIP-712 verdicts
  • Check token flags like admin active status and launcher deployment
  • Retrieve signed attestations pinned to specific Base blocks
Tools advertised by the last live check:
  • verify_b20_token
  • b20_stats

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 b20-check-mcp https://b20check.com/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 b20-check-mcp --url https://b20check.com/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable b20-check-mcp in your MCP settings.
Cursor configuration
{
  "mcpServers": {
    "b20-check-mcp": {
      "url": "https://b20check.com/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": {
    "b20-check-mcp": {
      "type": "streamableHttp",
      "url": "https://b20check.com/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start b20-check-mcp and inspect its tools.
VS Code configuration
{
  "servers": {
    "b20-check-mcp": {
      "type": "http",
      "url": "https://b20check.com/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 b20-check-mcp https://b20check.com/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": {
    "b20-check-mcp": {
      "url": "https://b20check.com/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": {
    "b20-check-mcp": {
      "serverUrl": "https://b20check.com/mcp"
    }
  }
}

Do you run B20 Check MCP?

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