Agent-ready email and messaging
129 verified email and messaging sites, 69 of them transactable — every one probed live, with the date it was checked. Figures generated 27 Sep 2026 06:32 UTC
Checks passed across the 140 probed hosts: Markdown negotiation 122 · Markdown twin at a predictable URL 91 · llms.txt 128 · API catalog 36 · MCP server card answers 94.
✓Sendmux sendmux.ai
Sendmux provides an email API for AI agents to send, receive, route, and manage email inboxes with failover and provider routing.
✓Email-Check.app email-check.app
Email-Check.app provides a real-time email validation API for signup flows, CRM hygiene, list cleaning, and deliverability operations.
✓PostStack poststack.dev
PostStack provides a European email API platform with REST, SMTP, and OAuth 2.0 support, hosted in Finland and GDPR compliant.
FI✓Resend resend-staging.com
Resend provides an email API for developers to send transactional and marketing emails at scale with a modern API.
✓Resend resend.com
Resend provides an email API for developers to send transactional and marketing emails at scale with CLI tools and extensive documentation.
✓FormsFort www.formsfort.com
FormsFort provides a backend service for HTML forms with email delivery, spam controls, file uploads, and webhook integrations.
✓Gratis Dansk Chat & Chatrum med Avatarer www.skyskraber.dk
Skyskraber is a Danish 2D chat platform for adults 18+ featuring avatars, missions, toplists, achievements, and virtual apartments.
DK✓تطوير الحقائب التدريبية d-tb.org
A leading Arabic site offering over 5000 ready-made and custom training kits with immediate email delivery.
SA✓Generect docs.generect.com
Generect is a platform for real-time B2B lead discovery and verification with API and CRM integration.
✓Maito getmaito.com
Maito is a newsletter platform for founders, publishers, and creators to build and manage an owned audience with publishing and social promotion tools.
✓JetEmail jetemail.com
JetEmail provides SMTP and API email delivery, inbound filtering, and marketing email services with subscriber-based pricing and unlimited sending.
✓OpenMail openmail.sh +1 more host on this domain
OpenMail provides an email API for AI agents to create inboxes, send and receive emails with real-time webhooks and attachment parsing.
✓AhaSend ahasend.mintlify.app +6 more hosts on this domain
AhaSend provides developer-first transactional email delivery with REST APIs, SMTP relay, and CLI tools, supporting fast delivery and transparent pricing.
✓Fax.Plus API apidoc.fax.plus
Documentation for Fax.Plus API enabling integration of online fax functionalities into workflows.
✓Broodnet broodnet.com +1 more host on this domain
Broodnet provides real email inboxes for AI agents with inbound from anywhere and controlled outbound sending.
✓Z-API Docs developer.z-api.io
Z-API provides a RESTful API to interact with WhatsApp Web, including message sending and webhook notifications.
✓DeBounce API developers.debounce.com
Technical overview and documentation of the DeBounce email validation API for developers.
✓Heymarket API Documentation developers.heymarket.com
Heymarket REST API enables sending messages, managing contacts, organizing conversations, and integrating with systems.
✓EuAtendo API Whats Delphi doc.apicomponente.com.br
Documentation for EuAtendo API providing WhatsApp integration with test servers and setup instructions.
BR✓Cleariflow API docs.cleariflow.com
Cleariflow API provides an email validation service that checks email deliverability, format, and quality via an API.
✓Connectly docs.connectly.ai
Connectly provides developer documentation for a WhatsApp Business messaging platform enabling scalable messaging and chatbot automation via API.
✓Contiguity docs.contiguity.com
Contiguity provides APIs for messaging, email, and identity verification with account creation and API key generation.
✓EmailBison Docs docs.emailbison.com
EmailBison Docs provides documentation to get started with the EmailBison API, including workflows and API calls.
✓emailr_ docs.emailr.dev
Documentation for Emailr platform to send transactional and marketing emails, manage contacts, and automate workflows via HTTP API.
✓Enrichley Docs docs.enrichley.io
Documentation for Enrichley, an API and platform for email validation, lead discovery, and AI assistant integration over MCP.
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