Community-Access GitHub Accessibility Scanner Integration
What Is the GitHub Accessibility Scanner?
The GitHub Accessibility Scanner (github/accessibility-scanner@v2) is an official GitHub Action that:
- Scans live URLs for accessibility barriers using axe-core in a headless browser
- Creates trackable GitHub Issues for each finding, with affected element, WCAG criterion, and remediation guidance
- Optionally assigns issues to GitHub Copilot for AI-powered fix suggestions and PR creation
- Caches results across runs for delta detection (new, fixed, persistent findings)
- Supports authenticated scanning (login flows, SSO, passkeys via Playwright auth context)
- Optionally captures screenshots and attaches them to filed issues
Current version: v2 (public preview)
Detecting Scanner Presence
To determine whether a repository has the GitHub Accessibility Scanner configured:
Workflow File Detection
Search for workflow files referencing the scanner action:
# Search in .github/workflows/ for the scanner action reference
grep -rl "github/accessibility-scanner" .github/workflows/
Pattern to match in YAML:
- uses: github/accessibility-scanner@v2
Workflow Inputs
When a scanner workflow is found, extract its configuration:
| Input | Required | Description |
|---|---|---|
urls |
Yes | Newline-delimited list of URLs to scan |
repository |
Yes | Repository (owner/name) where issues and PRs are created |
token |
Yes | Fine-grained PAT with write access (contents, issues, PRs, metadata) |
cache_key |
Yes | Filename for caching results across runs (e.g., cached_results-mysite.json) |
login_url |
No | Login page URL for authenticated scanning |
username |
No | Username for authentication |
password |
No | Password for authentication (via repository secret) |
auth_context |
No | Stringified JSON for complex authentication (Playwright session state) |
skip_copilot_assignment |
No | Set true to skip assigning issues to Copilot |
include_screenshots |
No | Set true to capture screenshots (stored on gh-cache branch) |
Parsing Scanner-Created Issues
The scanner creates GitHub Issues with a structured format. Agents should parse these fields:
Issue Identification
Scanner-created issues can be identified by:
- Author: The GitHub Actions bot that runs the workflow
- Labels: The scanner applies labels to categorize findings (typically accessibility-related labels)
- Body structure: Issues contain structured sections with violation details
Issue Body Structure
Scanner issues typically contain:
| Section | Content | Agent Use |
|---|---|---|
| Violation title | The axe-core rule that was violated | Map to help-url-reference for remediation docs |
| WCAG criterion | The specific WCAG success criterion | Used for severity scoring and compliance mapping |
| Affected element | CSS selector or HTML snippet of the failing element | Used by scanner-bridge to map to source code |
| Impact level | Critical, Serious, Moderate, or Minor | Direct mapping to agent severity model |
| Remediation guidance | How to fix the issue | Enriched by agent specialists with framework-specific fixes |
| URL | The page URL where the issue was found | Used for cross-referencing with local axe-core scans |
| Screenshot link | Link to screenshot on gh-cache branch (if enabled) |
Included in audit reports |
Severity Mapping
The scanner uses axe-core impact levels that map directly to the agent severity model:
| Scanner Impact | Agent Severity | Score Weight |
|---|---|---|
| Critical | Critical | -15 (both sources) / -10 (single source) |
| Serious | Serious | -7 (high confidence) |
| Moderate | Moderate | -3 (high confidence) |
| Minor | Minor | -1 |
axe-core Rule Correlation
The scanner uses axe-core under the hood. Scanner issue titles and violation IDs correspond to axe-core rules already cataloged in help-url-reference. Common scanner-reported rules:
| axe-core Rule ID | WCAG Criterion | Common Description |
|---|---|---|
image-alt |
1.1.1 | Images must have alternate text |
label |
1.3.1 | Form elements must have labels |
color-contrast |
1.4.3 | Elements must have sufficient color contrast |
link-name |
2.4.4 | Links must have discernible text |
html-has-lang |
3.1.1 | <html> element must have a lang attribute |
button-name |
4.1.2 | Buttons must have discernible text |
document-title |
2.4.2 | Documents must have <title> element |
bypass |
2.4.1 | Page must have means to bypass repeated blocks |
heading-order |
1.3.1 | Heading levels should increase by one |
aria-allowed-attr |
4.1.2 | ARIA attributes must be allowed for element role |
Caching and Delta Detection
The scanner uses a cache_key to persist results across workflow runs. This enables delta tracking:
| Status | Meaning |
|---|---|
| New | Issue found in current scan but not in cached results |
| Fixed | Issue in cached results but not found in current scan (issue auto-closed) |
| Persistent | Issue found in both current scan and cached results |
Cache Key Conventions
When setting up scanner integration, align the cache key with agent conventions:
- Use a descriptive name:
cached_results-{domain}-{branch}.json - Include branch context for branch-specific scanning
- The cache is stored as a GitHub Actions artifact
Correlation with Local Scans
Dual-Source Confidence Boosting
When both the GitHub Accessibility Scanner (CI) and a local axe-core scan (agent) find the same issue:
- Match by rule ID: Both sources use axe-core rule IDs (e.g.,
color-contrast,image-alt) - Match by URL: Compare the scanned URL from the scanner issue with the local scan target
- Match by element: Compare CSS selectors or HTML paths for the affected element
- Boost confidence: Findings confirmed by both sources automatically receive
highconfidence
Source Comparison Analysis
| Scenario | Interpretation | Action |
|---|---|---|
| Found by scanner AND local scan | High confidence -- confirmed by both | Report as high confidence, full severity weight |
| Found by scanner only | Environment-specific or intermittent | Report as medium confidence, note "CI-only finding" |
| Found by local scan only | New since last CI scan, or local-only condition | Report as medium confidence, note "local-only finding" |
| In scanner cache as "fixed" | Recently remediated | Track in delta section as resolved |
Copilot Fix Tracking
When the scanner assigns issues to GitHub Copilot:
Fix Lifecycle
| Stage | GitHub State | How to Detect |
|---|---|---|
| Issue created | Open issue, assigned to Copilot | assignee includes Copilot bot |
| Fix proposed | Open PR linked to issue | PR references issue number, author is Copilot |
| Fix reviewed | PR has review comments | PR review state is CHANGES_REQUESTED or APPROVED |
| Fix merged | PR merged, issue closed | Issue state is closed, linked PR is merged |
| Fix rejected | PR closed without merge | PR state is closed, not merged |
Querying Copilot Fix Status
# Find scanner issues assigned to Copilot
repo:{REPO} is:issue is:open assignee:copilot label:accessibility
# Find Copilot PRs from scanner issues
repo:{REPO} is:pr author:copilot-swe-agent label:accessibility
# Find merged scanner fixes
repo:{REPO} is:pr is:merged author:copilot-swe-agent label:accessibility
Structured Output Format
When scanner-bridge normalizes scanner issue data, it produces findings in this format:
{
"source": "github-a11y-scanner",
"ruleId": "color-contrast",
"wcagCriterion": "1.4.3",
"wcagLevel": "AA",
"severity": "serious",
"confidence": "high",
"url": "https://example.com/login",
"element": "button.submit-btn",
"description": "Element has insufficient color contrast ratio of 3.2:1 (expected 4.5:1)",
"remediation": "Change the text color or background to achieve at least 4.5:1 contrast ratio",
"githubIssue": {
"number": 42,
"url": "https://github.com/owner/repo/issues/42",
"state": "open",
"copilotAssigned": true,
"fixPR": null
},
"screenshot": "https://github.com/owner/repo/blob/gh-cache/screenshots/login-contrast.png"
}
Search Patterns for Scanner Issues
By Repository
repo:{OWNER}/{REPO} is:issue label:accessibility created:>{YYYY-MM-DD}
By Scan Run
Issues from a specific scan run share the same creation timestamp and batch pattern. Filter by:
- Creation date matching the workflow run date
- Common label set applied by the scanner
Cross-Repository Scanner Discovery
user:{USERNAME} is:issue label:accessibility sort:created-desc
org:{ORGNAME} is:issue label:accessibility sort:created-desc