MCP Server

Model Context Protocol (MCP) is an open standard for connecting AI agents to tools. szum exposes an MCP server so agents can render charts, validate configs, and browse themes directly.

Endpoint

POST https://szum.io/mcp

Authenticate with the same API key you use for POST /chart:

Authorization: Bearer YOUR_API_KEY

Tools

Tool	Description	Counts as render?
`render_chart`	Render a chart config, returns a URL to the image (expires in 1h)	Yes
`validate_chart`	Validate a config against the schema	No
`list_themes`	List available themes	No
`list_marks`	List mark types with properties	No
`get_examples`	Get example chart configs	No

Only render_chart increments your monthly render count. All other tools are free.

Resources

URI	Description
`szum://schema`	Full JSON Schema for chart configs
`szum://llms-txt`	Compact API reference

Connect from Claude Desktop

Add this to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "szum": {
      "type": "http",
      "url": "https://szum.io/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Connect from Claude Code

claude mcp add szum --transport http https://szum.io/mcp -H "Authorization: Bearer YOUR_API_KEY"

Connect from Cursor

Add this to your Cursor MCP settings (.cursor/mcp.json):

{
  "mcpServers": {
    "szum": {
      "type": "http",
      "url": "https://szum.io/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Usage and billing

MCP uses the same API key, rate limits, and monthly render allowance as the HTTP API. Each render_chart call counts as one render against your plan limit. Burst rate limits apply per key.