"Email" matching MCP servers:

Enables AI agents to check email HTML for delivery-breaking problems before sending, returning structured diagnostics with rule id, severity, line and column, along with a tool that lists every available rule. It runs with no filesystem, network or environment access, so agents can validate markup without gaining new permissions.

MCP server providing email client compatibility data from caniemail.com, enabling agents to lint HTML/CSS for email client support, check feature support across clients, and search for features by keyword, with verdicts including supported, unsupported, mitigated, and untested.

Enables security analysis through MCP-compatible clients, including URL phishing checks, email header verification, JWT decoding, password strength analysis, and leaked secret scanning in code.