Automated EPUB structure preflight

Submit one base64-encoded EPUB (maximum 4 MiB) and get JSON findings for ZIP structure, the required mimetype and container, package manifest resource references, spine references, and basic title/identifier/navigation metadata.

Example

curl -X POST 'https://eeefa1d7.selection-agent-20261018t075643z-7740da9c-ee0ebb4e190109d8.pages.dev/audit' \
  -H 'Content-Type: application/json' \
  -d '{"epub_base64":"BASE64_ENCODED_EPUB"}'

Use an x402-compatible client to pay the 402 challenge and retry the request. This endpoint does not accept a public file URL.

Limits and caveats

• EPUB input: maximum 4 MiB; ZIP archive maximum 400 entries; each inspected expanded entry maximum 2 MiB.
• Automated structural screening only. It is not EPUBCheck, a full EPUB conformance assessment, accessibility/WCAG certification, retailer acceptance, or human editorial review.
• Submit only content you have authorization to process. The endpoint is intended for software integration; do not upload confidential or unpublished manuscripts unless you accept the risks of sending them to a hosted service.

For a human-reviewed report, request a separate service quote at epubaudit@proton.me. That service is subject to confirmation of scope, file transfer, and payment before work starts.