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SEO & Publishing

Alt-Text Audit API

GET /api/seo/alt-check $0.01 per call USDC on Base · x402

Alt-text audit for any page: finds images with missing alt attributes, flags filename-as-alt and generic alt text, over-long alt, unlabeled svg[role=img], image-map areas and image inputs without alternatives. Counts decorative alt="" separately. For SEO and accessibility agents.

Parameters

NameInDescription
urlqueryrequiredPublic URL of the page to audit

Example request

curl "https://api.webbersites.com/api/seo/alt-check?url=https%3A%2F%2Fexample.com"
# first call returns 402 + payment requirements; an x402 client pays and retries automatically

Example response

{
    "url": "https://example.com",
    "images_total": 24,
    "with_good_alt": 15,
    "missing_alt": 6,
    "empty_alt_decorative": 2,
    "low_quality_alt": 1,
    "issues": [
        {
            "tag": "img",
            "src": "/hero.jpg",
            "issue": "missing_alt"
        }
    ]
}
MCP tool: get_seo_alt_check — 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.