Test the journeys people need
Review navigation, headings, links, forms, errors, dialogs, media, contrast, zoom, and keyboard operation. Use appropriate assistive-technology testing and involve people with disabilities where possible. Automated tools can identify some issues, but cannot establish all accessibility requirements. Fix underlying content and interaction problems rather than relying solely on an overlay.
Treat automation as assistance
A plugin may offer useful features, but its capabilities need evaluation on the actual website. It should not be described as an immediate, complete compliance solution or protection from lawsuits. Avoid invented percentages about how much accessibility a tool provides and unsupported claims about litigation rates or universal remediation costs.