Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun
Letterkeel: send email from your own domain via SMTP, Resend, SendGrid, Mailgun, Postmark
MCP server · by shawmena-dotcom
About
Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun is an MCP server published by shawmena-dotcom. Marketplaces we read that list it: 1 (Official MCP Registry). We first saw it on 2026-10-11 and have recorded no change since. As of our marketplace pass on 2026-10-13.
What it asks for
- Runs remotely
None of the marketplaces we read publishes its tools or the settings it asks for.
Requires: Authorization header
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Connect
No data for an automatic command: what its marketplaces declare does not say unambiguously how to connect it.
Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 1.0.1 | No figure published | Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
Nothing has moved on this plugin since we started watching it.
Possibly the same plugin
Listings that share a signal with this one but not enough for us to treat them as the same product.
- Bonafido: Business Domain Verification API
- Capturewren: Website Screenshot API for AI Agents (Image + Text)
- Commonkite: Free Image Search API, Creative Commons & CC0
- CyberMax Data
- DomainDNA: Tech Stack Detector, WHOIS & Domain Age API
- Feedpeck: RSS Feed Finder & Reader by Website
- Fieldwright
- Firmfold: Company Enrichment API
- HireHeat Jobs: Career Site Job Listings from 12,000+ Companies
- HireHeat: Hiring Signals & Company Job Postings by Domain
Forks and copies
Similar plugins
Products whose own names, descriptions, tools and skills are closest in meaning to this one, on every marketplace we read. Closeness is ranked within this list only.
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Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun
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Letterkeel: Send Email via SMTP, Resend, SendGrid & Mailgun
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securessmtp com.securessmtp/securessmtp
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mcp-server co.truncus/mcp-server
Send transactional emails from AI agents via Truncus. Validate, track delivery, and manage domains.
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vaemail io.github.vaemail/vaemail
Email infrastructure for AI agents: send, authenticate domains, track delivery, diagnose issues.
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mail-send dev.mailkite/mail-send
Send transactional email over a verified domain — templates, attachments, custom headers.
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SendGrid MCP — wraps SendGrid v3 API (api.sendgrid.com/v3)
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mailkite dev.mailkite/mailkite
Send email, manage domains, DNS, webhooks, templates, and inbound routing on MailKite
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Send and receive email, and manage templates, inboxes, contacts and broadcasts.
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Found by meaning, not by shared code or a shared repository: similar plugins stay separate products, and this is not a review or a recommendation.
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Add it to your projects and prove you maintain it with a file in its repository, a file on your domain or a DNS record. You get alerts when a marketplace lists it, drops it, changes its verified mark or what it asks for, and its remote endpoint goes on monitoring as a web service.
Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.