Emailens MCP
Analyze, audit, fix and diff HTML, MJML, Maizzle and React Email across 21 email clients.
Connect it
Settings → Connectors → Add custom connector
URL: https://emailens.dev/api/mcpSettings → Apps & Connectors → Advanced → Developer mode
Create connector with URL: https://emailens.dev/api/mcp{
"mcpServers": {
"mcp": {
"url": "https://emailens.dev/api/mcp"
}
}
}claude mcp add --transport http mcp https://emailens.dev/api/mcp{
"servers": {
"mcp": {
"type": "http",
"url": "https://emailens.dev/api/mcp"
}
}
}{
"mcpServers": {
"mcp": {
"command": "npx",
"args": [
"-y",
"@emailens/mcp@0.10.1"
],
"env": {
"EMAILENS_API_KEY": "<value>"
}
}
}
}claude mcp add mcp -- npx -y @emailens/mcp@0.10.113 tools, verified live
preview_emailread-onlyFull email compatibility preview , transforms HTML for 21 email clients, analyzes CSS, generates scores, simulates dark mode, checks inbox preview and email size.
analyze_emailread-onlyQuick CSS compatibility analysis , returns warnings and per-client scores.
audit_emailread-onlyComprehensive quality audit , CSS compatibility, spam, links, accessibility, images, inbox preview, size, templates, content overflow, visual bugs.
fix_emailread-onlyGenerate a structured fix prompt for email compatibility issues.
list_clientsread-onlyList all 21 supported email clients with IDs, names, rendering engines, dark mode support, and deprecation status. Use the returned IDs to filter other tools like preview_email or capture_screenshots.
diff_emailsread-onlyCompare two email HTML versions , shows score changes, fixed issues, and regressions per client.
check_deliverabilityread-onlyCheck email deliverability for a domain , SPF, DKIM, DMARC, MX, BIMI.
build_emailGenerate a cross-client-compatible email from a brief using Emailens's self-healing loop (generate → score across 21 clients → repair). Output stays in the framework you choose. Returns a runId immediately , poll get_build_status for progress and the final code. Requires a Pro/Team API key.
get_build_statusread-onlyCheck a build_email run by runId , returns status, iteration, best compatibility score, and the current best source once available.
sandbox_get_inboxRetrieve or auto-create your Emailens sandbox test email address for capturing test emails.
sandbox_list_messagesread-onlyList recently captured test emails in the Emailens sandbox.
sandbox_wait_for_emailread-onlyPoll and wait for a matching incoming test email in the sandbox (ideal for auth OTPs, magic links, transactional email assertions).
sandbox_get_messageread-onlyGet complete email details: HTML/text body, parsed headers, spam score, SPF/DKIM/DMARC auth status, and validated links.
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