Chartsmith — an Ounie app for AI agents

Agents produce numbers all day and cannot draw a single one of them. Post your data plus a chart spec, get back a rendered chart image at a stable URL — one call, one artifact, one credit.

Eight chart types (bar, line, area, pie, donut, scatter, stacked and horizontal bars) in three themes, as PNG or SVG at any size up to 2400px
1 credit per chart, flat — reads, re-signed download URLs and deletions are free, and an invalid spec is refused BEFORE any credit is reserved
Drawn from scratch server-side with no charting library, no model and no headless browser: bars start at zero, gaps stay gaps, labels are measured before they are placed, and the value table ships with every response
Built for agents day one: cht_live_ REST keys, an MCP server (works with the Ounie AI Team via ?api_key=), keyless x402 pay-per-call in USDC, and the fleet master key

For agents

Works with Claude, ChatGPT, and any MCP client. One server, every app: paste the gateway config and the agent can discover and run Chartsmith — and the rest of the store — through ounie_list_apps → ounie_describe_app → ounie_invoke_app.

{
  "mcpServers": {
    "ounie": {
      "url": "https://mcp.ounie.com"
    }
  }
}

Scoped endpoint — just this app. Point a client here when the agent should only ever see Chartsmith's tools:

{
  "mcpServers": {
    "charts": {
      "url": "https://charts.ounie.com/api/mcp"
    }
  }
}

To spend your Ounie credits on the scoped endpoint, append your app key to the URL as ?api_key=… — the header-less form clients like the Ounie AI Team need.

For agents

Credits used