MCP setup

This server speaks the Model Context Protocol so every endpoint you register also surfaces as a callable tool inside Claude (Desktop, Code, or any MCP-aware client). One endpoint definition → one REST route + one MCP tool, no duplicate code.

For the smoothest setup, use Claude.ai's custom-connector flow — it handles OAuth (Dynamic Client Registration + PKCE) for you, no JSON editing required.

  1. Settings → Connectors → Add custom server.
  2. Paste https://api.fulcrumgo.com/mcp/ as the server URL. Submit.
  3. Sign in via magic-link, approve the consent screen, and your tools appear in the conversation.

If you'd rather skip the OAuth handshake (e.g. for a trusted personal account), mint a URL token at /dashboard/url-tokens/ → + New URL token. Copy the full https://.../mcp/k/mcpurl_.../ URL it prints once and paste that into the same Claude.ai connector field. No bearer header needed — the token is part of the path.

Claude Desktop

Claude Desktop only natively supports stdio MCP servers, so connecting to a remote HTTP endpoint needs a small stdio shim. The standard one is mcp-remote.

Edit claude_desktop_config.json (location: ~/Library/Application Support/Claude/ on macOS, %APPDATA%\Claude\ on Windows):

{
  "mcpServers": {
    "this-api": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://api.fulcrumgo.com/mcp/",
        "--header",
        "Authorization: Bearer mcpsk_your_key_here"
      ]
    }
  }
}

Restart Claude Desktop. Open a new conversation; the available tools appear automatically — every endpoint registered with @endpoint(slug=...) surfaces as a tool named after its slug (e.g. the hello endpoint shows up as hello).

Claude Code

From your terminal:

claude mcp add this-api https://api.fulcrumgo.com/mcp/ \
  --transport http \
  --header "Authorization: Bearer mcpsk_your_key_here"

This writes the server entry into ~/.claude.json (user scope). Use claude mcp list to verify, and claude mcp remove this-api to detach. You can also point a session at an ad-hoc config with claude --mcp-config <file.json>.

Cursor

Cursor accepts remote MCP servers directly — no shim needed. Edit ~/.cursor/mcp.json (or the in-app settings):

{
  "mcpServers": {
    "this-api": {
      "url": "https://api.fulcrumgo.com/mcp/",
      "headers": {
        "Authorization": "Bearer mcpsk_your_key_here"
      }
    }
  }
}

Restart Cursor; tools appear under your configured server name.

Authentication

Use the same Authorization: Bearer mcpsk_<key> token used for REST. Each tool invocation counts against your credit quota — see the billing page for your current balance.

If your client supports OAuth-based MCP authentication (instead of a static bearer), point it at:

https://api.fulcrumgo.com/oauth/authorize/

The Authorization Server metadata is published at /.well-known/oauth-authorization-server and we support Dynamic Client Registration (DCR) per RFC 7591 so most clients self-register without operator action.

Troubleshooting

  • No tools show up: open Claude Desktop devtools (Help → Developer Tools), check the MCP server log for connection errors. Most common cause: wrong token.
  • Tools show but return errors: check the request log on /dashboard/usage/ for the failing call — status codes match the error codes guide.
  • Tool name ends with __v2 / __v3: the endpoint ships multiple versions and the suffix marks the non-default one. The unsuffixed name is the stable v1; pick the suffixed version only if you specifically need its behavior.

Local development

When developing endpoints locally, point your MCP client at http://localhost:8000/mcp/ (note: http, not https). Restart the client after registering a new endpoint — Claude reads the tool list once at connection time.