Agentic

MCP Integration

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The Tesser MCP server exposes every public API endpoint as a tool that AI agents can discover and invoke. It uses Streamable HTTP transport at:

Code
 
https://sandbox.tesserx.co/v1/mcp

Authentication uses the same Auth0 credentials as the REST API, in one of two ways:

• OAuth discovery (recommended) — the server advertises OAuth metadata, so clients that support the MCP authorization spec (e.g. Cursor) run the OAuth flow and refresh tokens for you. See OAuth discovery.
• Manual bearer token — a fallback for clients without OAuth discovery (e.g. Claude Code today). You fetch a token and set it as a header. See Manual token.

OAuth discovery

The MCP endpoint serves RFC 9728 metadata at /.well-known/oauth-protected-resource, pointing clients at our Auth0 server. A 401 also returns a WWW-Authenticate: resource_metadata hint, so a compliant client discovers everything with no extra config.

Cursor — .cursor/mcp.json

Code
 
{
  "mcpServers": {
    "tesser-payments": {
      "url": "https://sandbox.tesserx.co/v1/mcp",
      "auth": {
        "CLIENT_ID": "${env:TESSER_API_KEY}",
        "CLIENT_SECRET": "${env:TESSER_API_SECRET}"
      }
    }
  }
}

Cursor runs the OAuth flow on first use and refreshes tokens automatically.

Manual token

For clients without OAuth discovery, fetch a token and pass it as a header. Set it in the shell before launching your IDE:

Code
 
export MCP_TOKEN=$(bash scripts/mcp-token.sh)

Claude Code — .claude/settings.local.json

Code
 
{
  "mcpServers": {
    "tesser-payments": {
      "type": "url",
      "url": "https://sandbox.tesserx.co/v1/mcp",
      "headers": {
        "Authorization": "Bearer ${MCP_TOKEN}"
      }
    }
  }
}

Run /mcp in Claude Code to reload.

Cursor — .cursor/mcp.json

Code
 
{
  "mcpServers": {
    "tesser-payments": {
      "type": "url",
      "url": "https://sandbox.tesserx.co/v1/mcp",
      "headers": {
        "Authorization": "Bearer ${MCP_TOKEN}"
      }
    }
  }
}

Restart Cursor. (Prefer OAuth discovery, which refreshes tokens for you.)

Windsurf — .windsurf/mcp.json

Code
 
{
  "mcpServers": {
    "tesser-payments": {
      "type": "url",
      "url": "https://sandbox.tesserx.co/v1/mcp",
      "headers": {
        "Authorization": "Bearer ${MCP_TOKEN}"
      }
    }
  }
}

Restart Windsurf.

Token refresh

Manual tokens expire after ~24h; calls then fail with 401. Re-run the export above and restart your IDE (or /mcp in Claude Code). See Manual MCP Setup for details, or use OAuth discovery to avoid refreshing.