Social Card Generator API

POST /api/og/card $0.03 per call USDC on Base · x402

Social card generator: POST {title, subtitle, domain, theme, accent} and receive a finished 1200x630 OpenGraph card — PNG (base64) plus the source SVG. Three themes (dark, light, midnight), custom accent color, automatic text wrapping. Pairs with /api/og/check: check the page, then generate the missing card.

Parameters

Name	In		Description
`title`	body	required	Card headline (required, wraps to 3 lines, max 140 chars)
`subtitle`	body		Smaller supporting line (optional)
`domain`	body		Shown bottom-left in accent color (optional)
`theme`	body		dark (default), light, or midnight
`accent`	body		Hex accent color override, e.g. #ff6b35

Example request

curl -X POST "https://api.webbersites.com/api/og/card" \
  -H "Content-Type: application/json" \
  -d '{"title":"Ship Faster With Agent-Native APIs","subtitle":"Pay-per-call data for autonomous software","domain":"x402.webbersites.com","theme":"dark"}'
# first call returns 402 + payment requirements; an x402 client pays and retries automatically

Example response

{
    "width": 1200,
    "height": 630,
    "theme": "dark",
    "svg": "<svg …>",
    "png_base64": "iVBORw0…",
    "data_uri": "data:image/png;base64,…"
}

MCP tool: post_og_card — via npx -y webbersites-x402-mcp (local, key stays on your machine) or the remote endpoint https://api.webbersites.com/mcp.

How payment works

There is no signup and no API key. Call the endpoint; it replies 402 Payment Required with machine-readable payment requirements. Your client signs a USDC transfer authorization (EIP-3009, gasless) and retries with the X-PAYMENT header — @x402/fetch does this automatically. See the overview for a working snippet.