How much does a call cost?

$0.03 USDC on Base, paid with x402 before the operation runs.

POST JSON to /api/v1/accessibility/heading-structure-audit. An unpaid request returns 402. Pay the exact USDC amount on Base, then retry with payment-signature and Idempotency-Key.

Audit heading structure API

Read heading elements in source order and flag empty headings and skipped levels. A missing h1 is a potential issue, not a confirmed failure.

The Audit heading structure operation is part of the Accessibility Intelligence API on BRAINIAC.software. Read heading elements in source order and flag empty headings and skipped levels. A missing h1 is a potential issue, not a confirmed failure. It is exposed as POST /api/v1/accessibility/heading-structure-audit and priced at $0.03 USDC on Base. Payment uses the x402 exact scheme: an unpaid call returns HTTP 402 with payment requirements; after paying the exact USDC amount, retry the same request with a payment-signature header and Idempotency-Key. No account and no API key are required. Data sources for this product: HTML supplied in the request. One public HTML page fetched with the same public-page reader used by Web Intelligence. Limitations: Static HTML is not a WCAG conformance audit. JavaScript is not run, and browser or manual checks stay separate from confirmed issues. Contrast is calculated only when both colours are written on the same element. Stylesheet and inherited colours are not guessed. Outputs are compliance prechecks, drafts, or data lookups for human review. They are not official determinations, legal advice, identity confirmation, or certified filings. Related operations in this group include Audit HTML accessibility, Audit image alt text, Audit form accessibility, Audit link accessibility. Open the group documentation for the full request schema, field notes, and response examples before integrating.

POST$0.03 USDC

/api/v1/accessibility/heading-structure-audit

Example request

curl -i -X POST "https://www.brainiac.software/api/v1/accessibility/heading-structure-audit" \
  -H 'content-type: application/json' \
  -H 'Idempotency-Key: <fresh-64-character-random-hex-key>' \
  --data-binary @- <<'JSON'
{
  "html": "<html lang=\"en\"><body><h1>Welcome</h1><h3>Details</h3><h2></h2></body></html>"
}
JSON

An unpaid probe returns HTTP 402 with x402 payment requirements. After paying the exact USDC amount on Base, retry the identical request with a payment-signature header.

FAQ

Do I need an API key? No. Pay the listed USDC amount with x402.
What network? Base (eip155:8453), USDC.
Is this an official determination? No. Results are for human review against the cited sources.

Audit HTML accessibility — $0.05 USDC
Audit image alt text — $0.03 USDC
Audit form accessibility — $0.04 USDC
Audit link accessibility — $0.03 USDC

Audit heading structure API

Example request

FAQ

Related operations

Related APIs