3Stone Shield API · Accessibility engineering

Find accessibility problems. Verify that they were fixed.

Scan a deployed webpage for automatically detectable accessibility issues, receive prioritized remediation guidance, and rescan to confirm changes. Shield uses axe-core and clearly separates automated findings, AI-assisted proposals, and checks that still require human judgment.

New to APIs? See where Shield fits and copy the setup prompt →

Real axe-core scans, never fabricatedKey delivered instantly on signupCancel anytime

Automated and AI-assisted testing cannot determine complete WCAG conformance on their own - some criteria require human judgment. Shield distinguishes automatically detected findings, AI-assisted remediation proposals, and items flagged for manual review - it never certifies legal compliance.

Accessibility runScan → propose → verify
Live
Engine
axe-core
Evidence
Page grounded
Resolution
Verified by rescan
Quickstart

One request. Real data back.

Request

curl -X POST https://shield-api.3stoneai.com/api/v1/shield/scan \
  -H "Authorization: Bearer sk_shield_..." \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com"}'

Response

{
  "ok": true,
  "url": "https://example.com",
  "violations": [
    {
      "ruleId": "image-alt",
      "impact": "critical",
      "description": "Images must have alternate text",
      "wcagCriteria": ["wcag2a", "wcag111"],
      "occurrences": 3
    }
  ],
  "report": {
    "summary": "...",
    "prioritizedActions": [ /* AI-generated, plain-language, prioritized */ ]
  },
  "usage": { "callsUsedThisPeriod": 12, "callsLimitPerPeriod": 500 }
}

Every violation is real and traceable to an actual axe-core rule - never invented. The report object is AI-generated from those real findings (Claude), never claims "full compliance," and costs nothing extra - it's included in every call.

This is the quickstart. Full API reference covers every endpoint - scan history, AI-proposed remediations, rescan-based verification, and regression detection.

How It Works

Five real steps, not five buzzwords

1

Scan

Real axe-core scan of a live URL. POST /v1/shield/scan.

2

Understand

Every finding tagged with WCAG criteria, level, and whether it's automated or needs manual review.

3

Fix

Request an AI-proposed remediation grounded in the real HTML - explanation, diff, confidence, honest risk flags.

4

Verify

A real rescan confirms whether a specific finding is actually gone - not a self-reported "fixed" flag.

5

Prevent

Compare scans over time to catch new violations and regressions before they ship - wire it into CI.

Automated scanning and AI assistance find and help fix a real, meaningful subset of accessibility issues - they do not determine complete WCAG conformance on their own. Some criteria require a human reviewer. Shield is evidence and engineering assistance, not a compliance certificate.

Who This Is For

Built for people building on top of it, not end users

Web agencies

Offer real accessibility auditing to your own clients without building or maintaining a scanner.

Website builders & QA tools

Add real WCAG checking to your own product's pipeline with one integration.

Compliance & legal-tech platforms

Ground your own compliance features in real scan data instead of a static checklist.

Pricing

Flat monthly plans, real call caps

No per-seat pricing, no sales call. Pick a plan, get your key in the confirmation email.

Starter

$49/month

500 calls/mo

Get API Key
Honest About Scope

What this is - and isn't

Real automated WCAG 2.1/2.2 scanning via axe-core, an AI layer that proposes grounded code fixes, and real rescan-based verification - not a proprietary black-box score, not a fabricated compliance certificate. Every finding is labeled by how it was actually determined: automated (a definite axe-core violation), or needs review (a check axe-core itself couldn't resolve automatically) - never silently marked as passing just because nothing was flagged. Rate limits and usage are enforced per key - see your dashboard email for your current usage.

Already a customer? Open your dashboard ormanage your subscription. Wondering whether you need an API instead of a free scanner? Here's an honest comparison. Curious how the scanner itself is built? Read the engineering writeup.