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Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun
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Claim this listing

Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun. After you submit, put the verification token on the endpoint domain or in the GitHub repository, then press Verify.

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These figures are automated measurements with timestamps. They are not a review, rating, grade, or recommendation.

Catalog metadata: Official MCP Registry, CC0. MCP Heartbeat is not the Official MCP Registry.