"The most widely used models" matching MCP connectors:

MailercloudB

com.mailercloud.mcp

Connect AI assistants to Mailercloud, the email marketing platform. Tools to manage campaigns, contacts, lists, templates, automations, webhooks, senders, and transactional email — plus AI-powered campaign analysis, deliverability audits, and engagement insights.

Crevio's MCP server lets an agent run a real online business, not just read from one. It exposes a delegation surface (ask_crevio, start_task, wait_for_run, send_message, resolve_approvals) plus code_search and code_execute for calling the full Crevio REST API - products, customers, orders, email, socials, and sites.

AI-operated. Two free DKIM readers, no signup: reads keys, finds the selector. Paid roster $99.

Send WhatsApp, SMS, email or voice to a business with the compliance gate enforced.

Find and enrich leads, run multi-channel outreach, and manage the sales pipeline.

proofiteA

com.proofite

Read your AI-written daily briefing and retune the filter behind it: feeds, newsletters, topics.

Send e-cards to your human. The first store built for AI agents; free, no API key needed.

Fast email validation at the edge: syntax, MX records, disposable-domain detection.

email-verifierA

ai.verifox

Verify email deliverability & find business emails (single or bulk) via the Verifox API.

Your AI agent just got a marketing team. SendPulse MCP Server provides full access to the SendPulse marketing platform — email campaigns, CRM, chatbots, SMTP, and online courses. 134 methods across 5 modules.

Heldly reads your Google Calendar directly, places tentative holds on every host's calendar, and emails the invitee a one-click picker. The moment the invitee picks, Heldly confirms the chosen slot and deletes the siblings across every host's calendar in the same request. No reusable booking page, no in-app form, no calendar cleanup.

Gives an AI agent its own email address: create mailboxes, send and reply, read the inbox, and block until a reply arrives. Includes a draft lifecycle so a human can approve outbound mail before it sends.

Emailable MCP — wraps the Emailable email verification API (emailable.com)

Hunter.io MCP — wraps the Hunter.io email finder & verification API (hunter.io)

Klaviyo MCP Pack — wraps the Klaviyo API for email marketing

Open-source MCP server that gives AI agents access to real email and calendar in one npm install. Solves the problem of AI agents hitting a wall when they need your inbox.

Giggal.ai is an email verification tool that runs a deep mailbox existence check on every address and verifies catch-all/accept-all and even SEG protected emails. Your bounce rate stays under 5%, and the 30% of every B2B list that other tools flag as "Risky" becomes deliverable again.

Authenticated email gateway for AI agents. Each agent gets its own deliverable email address with SPF/DKIM-verified inbound and optional human-in-the-loop approval on outbound. 18 tools covering send, receive, reply with threading preserved, and HITL approval queue.

Command your AI agents by voice: PTT rooms, channels, E2EE DMs, agent email, private recall.

Manage Microsoft 365 email, calendar, contacts and inbox rules via the Graph API with OAuth 2.0.