# @margint-ai/mcp

> Query your Margint per-customer AI margin from Claude Desktop, Cursor, or any MCP client.

Ask the LLM "which customers are losing me money this month?" and have it pull the answer from your Margint workspace. Read-only, scoped to a single API key.

## Install

Add to your MCP client config (Claude Desktop example, `~/Library/Application Support/Claude/claude_desktop_config.json`):

```json
{
    "mcpServers": {
        "margint": {
            "command": "npx",
            "args": ["-y", "@margint-ai/mcp"],
            "env": {
                "MARGINT_API_KEY": "m_live_..."
            }
        }
    }
}
```

For Cursor: same JSON, in **Settings → Features → MCP**.

Get a key at [app.margint.dev](https://app.margint.dev) → **Settings → API Keys**.

## Tools exposed

| Tool                      | What it does                                                |
| ------------------------- | ----------------------------------------------------------- |
| `margint_list_customers`  | List tracked customers with margin, revenue, cost           |
| `margint_get_customer`    | Drill into one customer's costs by feature/model            |
| `margint_cost_overview`   | Workspace-wide totals + breakdowns by provider/model/feature |
| `margint_check_budget`    | Check whether a customer is at/over their monthly budget    |

All tools accept a `range` parameter (`7d`, `30d`, `90d` — default `30d`).

## Configuration

| Env var              | Default                  | Notes                                |
| -------------------- | ------------------------ | ------------------------------------ |
| `MARGINT_API_KEY`    | _required_               | Your workspace API key               |
| `MARGINT_BASE_URL`   | `https://app.margint.dev` | Override for self-hosted Margint     |

## Privacy

The MCP server only forwards your prompts to Margint's read API — it never reads your LLM call payloads. The API key scopes access to a single workspace.

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MIT licensed. © Margint. Questions: `hi@margint.dev`.