Use BiOS from Claude Desktop

Claude app for macOS and Windows

Works today

Claude Desktop was the first app to support MCP and remains the easiest way to use BiOS conversationally. After a two-minute setup, a plain chat with Claude can upload datasets, start training runs, and deploy the results.

Before you start

You need a BiOS API key. In your dashboard, open API Keys, click Create API Key, pick a permission preset, and copy the sk_live_ key. It is shown only once.

Node.js 18 or newer must be installed; the server runs with npx, so there is nothing else to install.

Setup

1
Open the config file
In Claude Desktop, open Settings, choose the Developer tab, and click Edit Config. This creates and opens claude_desktop_config.json if it does not exist yet.
macOS: ~/Library/Application Support/Claude/claude_desktop_config.json. Windows: %APPDATA%\Claude\claude_desktop_config.json.

Add the BiOS server

Paste this into the file (or merge the usfbios entry into your existing mcpServers block) and save:

claude_desktop_config.json

{
  "mcpServers": {
    "usfbios": {
      "command": "npx",
      "args": ["-y", "@usfbios/mcp-server"],
      "env": {
        "USFBIOS_API_KEY": "sk_live_your_api_key"
      }
    }
  }
}

3
Restart Claude Desktop
Quit the app completely (not just the window) and reopen it. Claude Desktop launches MCP servers at startup.
4
Check the tools menu
Click the tools icon in the chat input area. You should see the usfbios server with its full tool list. Now just ask Claude to do something on BiOS.

Check that it works

The tools icon in the chat input lists the usfbios server without a warning triangle.
Ask "Check my BiOS wallet balance". Claude should request permission to call get_wallet_balance and return your credits.

Try these prompts

“Search for Llama models under 13B parameters and recommend a GPU for LoRA fine-tuning”

“Upload ~/data/support-qa.jsonl and start an SFT job on Llama 3.1 8B with LoRA”

“What is the status of my running training jobs? Show the loss curve for the latest one”

“Deploy my finished fine-tune and give me the endpoint URL”

Your assistant has 38 BiOS tools in total. The tool reference documents each one.

Troubleshooting

The server does not appear after a restart

Make sure you fully quit the app (Cmd+Q on macOS, or quit from the system tray on Windows) rather than closing the window. Also validate the JSON: a trailing comma is the most common cause.

The server never starts, or logs show "npx: command not found"

The MCP server runs on Node.js. Install Node 18 or newer from nodejs.org, restart your client, and try again. Run npx -y @usfbios/mcp-server in a terminal to confirm it starts (it waits for input; press Ctrl+C to exit).

Tools appear but every call fails with an authentication error

Check that USFBIOS_API_KEY is set to a key that starts with sk_live_ and has not expired. Keys are shown only once at creation, so if in doubt create a fresh one under Dashboard, then API Keys.

A tool call fails with a permission error

Your key may be scoped too narrowly. Ask the assistant to call introspect_api_key to see exactly which scopes the key has, then create a key with the preset you need (Read Only, Training, or Full Access).

Frequently asked questions

Do I need a paid Claude plan?

Local MCP servers work in Claude Desktop on free and paid plans. You only need a BiOS account and an API key.

Does this work in the Claude mobile app or on claude.ai?

Yes, through the hosted connector instead of this local setup: add https://mcp.usbios.ai/mcp as a custom connector and sign in with your BiOS account. The Claude on the web guide walks through it. Claude Desktop can use either path.