# machinegrade validate MCP server

> Validates AI-generated JSON, OpenAPI responses, and SQL syntax against specified contracts to ensure deterministic output quality.

- Repository: https://github.com/machinegrade/validate
- Page: https://hostedmcp.org/servers/machinegrade/validate
- Transport: stdio, remote
- Stars: 2
- License: MIT
- Latest version: 0.1.2

## Install

### Claude Code

```sh
claude mcp add --env 'SANDBOX_API_KEY=<YOUR_SANDBOX_API_KEY>' validate -- npx -y @machinegrade/validate
```

### Cursor (`~/.cursor/mcp.json`)

```json
{
  "mcpServers": {
    "validate": {
      "command": "npx",
      "args": [
        "-y",
        "@machinegrade/validate"
      ],
      "env": {
        "SANDBOX_API_KEY": "<YOUR_SANDBOX_API_KEY>"
      }
    }
  }
}
```

### VS Code (`.vscode/mcp.json`)

```json
{
  "servers": {
    "validate": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@machinegrade/validate"
      ],
      "env": {
        "SANDBOX_API_KEY": "<YOUR_SANDBOX_API_KEY>"
      }
    }
  }
}
```

### VS Code CLI

```sh
code --add-mcp '{"name":"validate","type":"stdio","command":"npx","args":["-y","@machinegrade/validate"],"env":{"SANDBOX_API_KEY":"<YOUR_SANDBOX_API_KEY>"}}'
```

### Claude Desktop (`claude_desktop_config.json`)

```json
{
  "mcpServers": {
    "validate": {
      "command": "npx",
      "args": [
        "-y",
        "@machinegrade/validate"
      ],
      "env": {
        "SANDBOX_API_KEY": "<YOUR_SANDBOX_API_KEY>"
      }
    }
  }
}
```

### Codex

```sh
codex mcp add validate --env 'SANDBOX_API_KEY=<YOUR_SANDBOX_API_KEY>' -- npx -y @machinegrade/validate
```

### Codex config.toml (`~/.codex/config.toml`)

```toml
[mcp_servers.validate]
command = "npx"
args = ["-y", "@machinegrade/validate"]

[mcp_servers.validate.env]
SANDBOX_API_KEY = "<YOUR_SANDBOX_API_KEY>"
```

### Gemini CLI

```sh
gemini mcp add -s user -e 'SANDBOX_API_KEY=<YOUR_SANDBOX_API_KEY>' validate npx -- -y @machinegrade/validate
```

### Gemini settings.json (`~/.gemini/settings.json`)

```json
{
  "mcpServers": {
    "validate": {
      "command": "npx",
      "args": [
        "-y",
        "@machinegrade/validate"
      ],
      "env": {
        "SANDBOX_API_KEY": "<YOUR_SANDBOX_API_KEY>"
      }
    }
  }
}
```

## Environment variables

| Name | Required | Secret | Description |
|---|---|---|---|
| `SANDBOX_API_KEY` | yes | yes | API key issued via POST https://api.machinegrade.dev/keys (free tier: 500 calls/month) |
| `SANDBOX_URL` | no | no | Base URL of the validate API |

## FAQ

### What can I validate with this server?

You can validate JSON artifacts against a JSON Schema, check API response bodies against an OpenAPI specification, and verify SQL syntax for specific dialects.

### Is there a free tier available?

Yes, there is a free tier that allows for 500 calls per month with a rate limit of 60 calls per minute.