"An email protocol for sending and receiving messages" matching MCP servers:

Real-time email verification API with syntax, MX, disposable detection, role-based flags, quality score 0-100. Built for agent outreach pipelines with pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Find professional email addresses from name + company domain. Tests 15+ patterns against MX records with confidence scoring, with pay-per-call via x402.

Enables Claude Code to create HubSpot marketing email drafts from Markdown and Word documents with automatic image handling and brand guidelines.

Enables finding and verifying work emails for contacts through a waterfall of provider keys, with per-provider cost attribution and verification after each finder.

Official MCP server for Ballast: connect AI agents to manage cold email campaigns, deliverability warmup, lead lists, and inbox replies.

Enables AI agents to interact with ActiveNet OpenAPI services for managing organizations, activities, customers, facilities, and more.

Validates email deliverability, assesses domain credibility, and scores B2B leads from A-F to help prioritize outreach, with batch processing and a free tier.

Finds, filters, and verifies local-business leads on demand; every returned email carries a verification receipt (verifier, verdict, timestamp). Credit-based with per-key spend budgets; 25 free validated leads at signup.

Provides interactive tools to explore AFAS customer data and employee leave information, including bubble charts, leave balance reports, and detailed leave cards.

Enables MCP clients to inspect and authenticate with Podio APIs, manage items, tasks, apps, spaces, and communications, search Podio data, and generate TypeScript field configurations.

Official Cursor plugin enabling natural-language management of your SideShift company—discovering creators, managing campaigns and contracts, communicating with your network, and inspecting analytics through a secure OAuth-linked MCP server.

Enables AI clients to securely interact with Salesforce data using natural language, translating prompts into structured queries for analysis, reporting, and business insights.

Live LinkedIn data for AI agents: 44 tools for profiles, companies, jobs, posts, people search, job-change signals and email finding. Hosted remote server (streamable HTTP) - your agent never touches your own LinkedIn account. 300 free credits on signup, no card. Dockerfile in repo bridges stdio clients to the hosted endpoint via mcp-remote.

Enables AI assistants to securely access and interact with Odoo data through natural language, supporting full CRUD operations, OAuth 2.1 and API key authentication, and granular per-model permissions.

Freento MCP is a native Magento 2 extension that implements the Model Context Protocol (MCP) — an open standard for connecting AI assistants to external data sources. This server acts as a secure, direct bridge between your Adobe Commerce / Magento 2 store and LLM-powered assistants (like Claude, ChatGPT, and others), allowing you to manage and audit your store using natural language.

Enables AI clients to securely access and query Zoho CRM data using natural-language prompts, returning structured results for analysis and reporting. It supports sales pipeline tracking, lead analysis, team performance reporting, and other CRM use cases through self-hosted deployment.

MCP server for the Mamba Labs People Finder & Email Verifier actor on Apify. Give it a company domain, name or LinkedIn URL and it returns the people at that company who match your role, seniority and department filters, each as a structured contact record with an optional verified business email.

Unified MCP server combining Hunter.io email finding with Apollo company intelligence for B2B lead enrichment.

Enables AI assistants to enrich contacts and build audiences via the YourICP API. Provides tools to set an API token, submit contact lookups by email or LinkedIn URL, and poll for enrichment results.

MCP server for emailfinder.dev that enables AI assistants to find verified professional email addresses via name/domain, LinkedIn URLs, company domains, roles, and email validation.

Outbound sales agent for Claude Code. MCP server handles prospect list building, dedup, quotas, and structured rejection feedback, while the plugin runs per-prospect research, email writing, Gmail sending, and reply tracking. Open source, self-hostable.

MCP server providing 1:1 tool parity with Arcade.dev's HubSpot Conversations API toolkit, enabling reading and sending conversation messages, managing threads, inboxes, channels, and custom channels from any MCP client.

Enables AI agents to automate Facebook lead generation and CRM tasks such as searching leads, sending friend requests, managing contacts, broadcasting messages, and tracking growth metrics.

Official Model Context Protocol server for 100Hires — the applicant tracking system for recruiting teams. Exposes the full 100Hires API v2 as 130 MCP tools, enabling AI assistants to manage candidates, jobs, applications, interviews, messages, and more.

Analyze LinkedIn & email outreach campaigns, track pipeline performance, and review lead conversations for RevOps, Sales Managers, and SDR teams.

Enables AI assistants to access toflow.ai workspace for prospecting, multi-channel outreach (email, LinkedIn, WhatsApp), sequences, enrichment, CRM, and AI automations.

Enables sending SMS messages, managing contacts, campaigns, and inbox from AI assistants like Claude and ClickUp.

Enables finding B2B leads with verified work emails, finding and verifying email addresses, and running cold email outreach from any MCP client.

Enables AI assistants to securely connect to a vybeflow tenant for multi-channel messaging operations such as reading inbox tickets, looking up contacts, checking campaign progress, and sending messages under scoped permissions.

Provides tools for AI agents to query customers by email, list open deals, and update deal stages with business rule enforcement.