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 07:19 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.
✓Hypersender docs.hypersender.com
Hypersender provides API documentation for sending messages via WhatsApp and SMS, including setup and usage instructions.
✓IndiePitcher docs.indiepitcher.com
IndiePitcher provides documentation for sending transactional and marketing emails via SDKs, REST API, and SMTP for startups.
✓Kapso Documentation docs.kapso.ai
Kapso Documentation provides developer resources for integrating and automating WhatsApp messaging via API and SDKs.
✓docs docs.kurrier.io
Documentation for Kurrier email API service explaining setup and sending email via providers and identities.
✓Lettr docs.lettr.com
Lettr is an email infrastructure platform for developers offering transactional and marketing email delivery, inbound parsing, and tracking via APIs.
✓MailCare Documentation docs.mailcare.io
MailCare Documentation provides instructions on API authentication, token generation, base URL usage, and testing with curl commands.
✓Meseji Documentation docs.meseji.app
Official WhatsApp Business API integration and AI tools for scalable customer engagement with developer-friendly API and template management.
✓MessageDesk Support Docs docs.messagedesk.com
Documentation for MessageDesk, a shared SMS inbox for teams to onboard, connect phone numbers, send group texts, and collaborate.
✓MigmaAI docs.migma.ai
Documentation for MigmaAI, an API for generating, editing, validating, and sending on-brand emails using AI.
✓Notifuse Documentation docs.notifuse.com
Documentation for Notifuse, a platform providing tools for email campaigns, transactional emails, and notification systems.
✓Orsay Docs docs.orsay.ai
Documentation for Orsay AI sales automation on WhatsApp personal, WhatsApp Business API, and Instagram inbound channels.
✓Paubox API Docs docs.paubox.com
Paubox provides HIPAA compliant email infrastructure with APIs for transactional email, marketing campaigns, and patient data collection via forms.
✓Poku Docs docs.pokulabs.com
Poku provides a unified API for AI agents to send SMS, WhatsApp, Slack messages, and place phone calls globally.
✓ProBase Docs docs.probaseapp.com
Instructions for creating a Probase account, setting up business profile, verifying email, and inviting team members.
✓Rasayel docs.rasayel.io
Rasayel provides documentation for WhatsApp Business messaging, campaigns, automations, integrations, and developer APIs.
✓Sanitize Email API Docs docs.sanitizeemail.com
Documentation for Sanitize Email API providing email validation, SMTP verification, bulk processing, and API key management for developers and businesses.
✓SendKit docs.sendkit.dev
SendKit provides an email API with SDKs for multiple languages to send transactional emails and manage domains and webhooks.
✓SendPost Docs docs.sendpost.io
SendPost provides API and SMTP relay for sending, tracking, and analyzing emails with advanced deliverability tools and integrations.
✓Sendrealm Documentation docs.sendrealm.com
Sendrealm Documentation provides guides and API references for transactional email, push notifications, templates, customer events, and automation building.
✓TerraReach Documentation docs.terrareach.com
TerraReach Documentation provides detailed information on setting up accounts, API references, pricing, and terms for the TerraReach SMS gateway service in Sri Lanka.
✓Unosend docs.unosend.co
Unosend is a transactional email service for developers offering REST API and SMTP for sending time-sensitive emails.
✓Bouncer docs.usebouncer.com
Bouncer provides an API to validate email addresses and verify their deliverability with real-time and batch endpoints.
✓useSend docs.usesend.com
useSend provides open source email sending API documentation including domain setup, API keys, SDKs, and SMTP support.
✓Zenzap docs.zenzap.co
Zenzap is a chat platform for business team collaboration, task management, and integration with tools like Google Calendar and Zoom.
✓Peerlist Help Center help.peerlist.io
Step-by-step guide on creating a Peerlist profile including signup, email verification, username selection, and LinkedIn autofill.
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