Email Validator AI MCP vs Emailens MCP

audit_email

Comprehensive email quality audit: CSS compatibility, spam scoring, link validation, accessibility, images, inbox preview, size (Gmail clipping), template variables, content overflow, visual fallbacks, dark-mode and mobile text contrast, design consistency, structural faults in Outlook-only VML (which lives inside conditional comments and is invisible to every other check), and style survival: CSS a client parses correctly and then discards, such as a stylesheet past Gmail's 16 KB ceiling or every rule after a `}}`, which no support matrix can express. For HTML input, findings tied to a specific element carry loc (line, column, offset) so you can edit the exact source. Compatibility is collapsed to one finding per problem listing the clients it affects; pass detail:'full' for the per-client breakdown with fix snippets. Use skip to omit checks and clients to narrow which clients are reported.

fix_email

Generate a structured fix prompt for email compatibility issues. Returns markdown with the original code, detected issues (CSS or structural), fix snippets, and format-specific instructions. Use after preview_email or analyze_email.

list_clients

List every supported email client with IDs, names, engines, and dark mode support.

diff_emails

Compare two email HTML versions, shows score changes, fixed issues, and newly introduced issues per client. Use after making fixes to verify improvements.

check_deliverability

Check email deliverability for a domain: SPF, DKIM, DMARC, MX, and BIMI records. Returns a score (0-100) and actionable issues. Uses DNS lookups (no API key needed).

capture_screenshots

Capture real email screenshots across 21 clients (Gmail, Outlook, Apple Mail, etc.) with light and dark mode variants. Screenshots are rendered in real browsers and hosted on CDN. Requires EMAILENS_API_KEY env var — free plan at emailens.dev?ref=mcp.

share_preview

Create a shareable link for an email preview. Recipients see the full analysis without needing an account. Requires EMAILENS_API_KEY env var and Dev plan ($9/mo).