Stumpy

The MCP plugin lets your agent connect to external MCP servers, giving it access to tools and capabilities beyond what Stumpy provides built-in. If a service offers an MCP server, your agent can use it.

What It Does

MCP (Model Context Protocol) is a standard for connecting AI agents to external tools. Once you add an MCP server, your agent can use the tools that server provides.

For example, you might connect your agent to:

• A company's internal API exposed as an MCP server
• A specialized data service
• Custom tools you've built for your own workflow
• Third-party services that offer MCP endpoints Many popular services are already listed as ready-made cards on the Connect an App page. Use a custom MCP server for anything that isn't.

Adding an MCP Server

1. On your agent's page, click "Connect App" in the sidebar
2. Scroll to the "Custom MCP Server" card and click Enable (or Manage, if it's already on)
3. On the MCP Servers page, fill in the Add MCP Server form: - Server Name: a name for your reference - Server URL: the MCP endpoint, for example https://example.com/mcp - Headers (optional): click "+ Add header" to send custom headers, such as an API key, with every request. Up to 10 per server.
4. Click Add Server Adding a server turns on the MCP plugin if it isn't on already. You can connect multiple MCP servers.

Servers That Use OAuth

You don't pick an authentication method. Stumpy checks each server when you add it. If the server requires you to sign in, it shows "Needs authentication" with an Authenticate button. Click it and sign in with that service. If the sign-in later expires, the button changes to Re-authenticate.

How Your Agent Uses External Tools

Once connected, the tools from external servers appear alongside your agent's built-in tools. Your agent uses them automatically based on what you ask.

For example, if you connect an MCP server that provides a "query_database" tool, you can ask your agent "look up the latest sales figures" and it will use that tool to fetch the data.

You don't need to tell your agent which tools to use. It sees the available tools and their descriptions and chooses the right one for the task.

Removing a Server

On the MCP Servers page, click Disconnect next to the server. To remove every MCP server at once, click the "x" next to MCP in the sidebar's Connections list and confirm.

MCP Servers vs. MCP Setup

These are two different things:

MCP Servers (this page) lets your agent connect to external MCP servers to use their tools. Your agent is the client, calling out to other servers.

MCP Setup lets you manage your Stumpy agents from MCP clients like Claude Code, Claude Desktop, or ChatGPT. You are the client, managing your agents from external tools.

They can be used together. Your agent can use tools from external servers, and you can manage your agents from MCP clients.

Limitations

• The external MCP server must be reachable over the internet by URL
• Header values and sign-in credentials are encrypted before storage
• Tool availability depends on the external server being online and responsive
• Your agent trusts the tools provided by connected servers, so only connect to servers you trust