> ## Documentation Index
> Fetch the complete documentation index at: https://docs.universalbench.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart

> Connect UniversalBench to your AI in under five minutes.

There are two ways to connect UniversalBench. Choose the one that matches how you are using it.

## Option A: Connect via the Anthropic Connectors Directory (recommended for Claude.ai)

If you found UniversalBench in the Claude.ai connectors directory, just click **Connect**. The OAuth flow handles everything. You will be asked to sign in or create an account, then Claude.ai is connected automatically. No URL to copy, no config file to edit.

That is it. Skip to [Run your first call](#run-your-first-call).

## Option B: Connect with a personal URL (Claude Desktop, Cursor, Claude Code, custom agents)

For any MCP client outside of Claude.ai, sign up at [universalbench.dev](https://universalbench.dev). After you verify your email, your dashboard shows your personal MCP URL:

```
https://universalbench-mcp.penantiaglobal.workers.dev/u/ubk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
```

Treat this URL like a password. Anyone with it can make calls billed to your account.

<Tabs>
  <Tab title="Claude Desktop">
    Edit `~/Library/Application Support/Claude/claude_desktop_config.json` on macOS or `%APPDATA%\Claude\claude_desktop_config.json` on Windows:

    ```json theme={null}
    {
      "mcpServers": {
        "universalbench": {
          "url": "https://universalbench-mcp.penantiaglobal.workers.dev/u/ubk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
        }
      }
    }
    ```

    Restart Claude Desktop. UniversalBench appears in the tool list within seconds.
  </Tab>

  <Tab title="Cursor">
    Add to your Cursor MCP config:

    ```json theme={null}
    {
      "mcpServers": {
        "universalbench": {
          "url": "https://universalbench-mcp.penantiaglobal.workers.dev/u/ubk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
        }
      }
    }
    ```
  </Tab>

  <Tab title="Claude Code">
    From any directory:

    ```bash theme={null}
    claude mcp add universalbench https://universalbench-mcp.penantiaglobal.workers.dev/u/ubk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    ```
  </Tab>

  <Tab title="Direct HTTP">
    Call the API directly. The URL is the auth, no header needed:

    ```bash theme={null}
    curl -X POST https://universalbench-mcp.penantiaglobal.workers.dev/u/ubk_your_key \
      -H "Content-Type: application/json" \
      -H "Accept: application/json, text/event-stream" \
      -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"ub_write","arguments":{"code":"print(sum(range(100)))"}}}'
    ```
  </Tab>
</Tabs>

## Run your first call

Ask your AI something that requires execution:

> Use UniversalBench to find all prime numbers under 10,000 and tell me the largest gap between consecutive primes.

Your AI routes the heavy lifting to UniversalBench, which runs the Python and returns just the answer. Your AI synthesizes a clean response from a small result instead of generating thousands of tokens in its own context.

## What to try next

<Columns cols={2}>
  <Card title="Web search with live data" icon="globe">
    Ask your AI to search the web for current information. UniversalBench returns clean snippets with sources.
  </Card>

  <Card title="Invoke any LLM" icon="brain">
    Use `invoke_llm` to call models from any provider on demand. Compare outputs, route by cost, or run a cheap model as a first pass.
  </Card>

  <Card title="Keep state across calls" icon="database">
    Pass `session_id` so your Python variables and imports persist between calls. Build a dataframe once, query it many times.
  </Card>

  <Card title="Store secrets safely" icon="lock">
    Use `secrets_vault` to store API keys encrypted server side. Your AI uses them by name without ever seeing the value.
  </Card>
</Columns>

## Pricing

You start with 1,000 free calls every month, no credit card required. After that, top up your wallet starting at \$5 and pay \$0.008 per call. No subscription, funds never expire. See the [billing page](/billing) for the full breakdown.

## Need help

Email [hello@universalbench.dev](mailto:hello@universalbench.dev). The dashboard at [universalbench.dev](https://universalbench.dev) shows your usage, wallet balance, and lets you rotate your URL if needed.