MCP Server

Connect AI agents to szum via Model Context Protocol.

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

No API key needed. Connect and start rendering charts immediately – up to 200 renders per month per IP, shared with keyless GET. For higher limits, add an API key:

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
generate_signed_url	Generate a signed URL for embedding charts in emails and tags (Pro)	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. generate_signed_url requires a Pro plan – renders via the generated URL count against your monthly limit (CDN cache hits do not).

Resources

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

Connect from Claude Code

claude mcp add szum --transport http https://szum.io/mcp

For higher limits, add your API key:

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

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"
    }
  }
}

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

Connect from Cursor

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

Usage and billing

Without an API key, each render_chart call counts against the IP-based limit of 200 renders per month, shared with keyless GET /chart. With an API key, renders count against your plan limit. All other tools are free. The generate_signed_url tool is only available with a Pro API key.

API Endpoint

POST JSON, get an image. Or embed via GET.

Authentication

GET embeds are keyless. Sign up for an API key to unlock POST requests and signed URLs.