How agents should think about email.
Architecture, patterns, and deliverability from the team building email infrastructure for AI agents.
We write about agent email patterns, deliverability, and security. These posts explain the decisions behind the API. They’re technical. We don’t write fluff. Pick the topic that matters to you right now.
AI Mail: Dedicated Email APIs for Autonomous Agents
How developers wire autonomous AI agents to dedicated email APIs — covering architecture, SPF/DKIM/DMARC, threading, parsing, and deliverability patterns.
Mails.ai vs Resend vs Postmark for AI Agents
Compare Mails.ai, Resend, and Postmark to choose the best transactional email API for AI agents, inbound parsing, MCP, and deliverability.
What Is a .ai Email Address? How AI Agents Use Real Domains
A .ai email address uses the .ai country-code TLD for the domain. Learn how AI agents use real email domains for identity, deliverability, and async workflows.
Email Deliverability for Automated and AI Senders
Email deliverability for automated and AI senders explained: SPF, DKIM, DMARC, IP warming, reputation management, and sending patterns that keep agents out of spam.
Unique Reply-To Address | Route Agent Replies Reliably
Learn how a unique reply-to address lets each agent route replies, preserve threading, verify identity, and process inbound email safely.
AI Email API vs Transactional Email API: Key Differences
Learn what an AI email API is, how it differs from a transactional email API, and which architecture your agent or application actually needs.
AI Agent Email API: Send, Parse & Route Inbound Mail
mails.ai handles transactional sending and inbound parsing for AI agents — webhooks, reply routing, and thread tracking in one API. See the docs and quickstart.
B2B Contact Database Architecture for Agent-Driven Email
How to design a contact database that supports agent-driven email workflows. Covers schema design, enrichment via inbound parsing, verification loops, and API integration patterns for B2B teams.
B2B Leads Using SEO: How Search Traffic Converts with Agent-Driven Email
How B2B teams use SEO to attract high-intent visitors and convert them into qualified pipeline using AI agent email workflows, structured reply handling, and automated follow-ups.
Best B2B Demand Generation Tools for 2026
Compare the top demand gen platforms and contact discovery tools B2B revenue teams use to fill pipeline and close more deals in 2026.
AI Agent Transactional Email Patterns for Developers
Learn how to send transactional email from an AI agent for OTPs, magic links, and notifications with secure, reliable delivery patterns.
Top B2B Pipeline Tools for Revenue Teams in 2026
What B2B revenue teams actually use to find accounts, verify contacts, and fill pipeline — data providers, intent platforms, and enrichment tools compared.
Transactional Email Pipeline: OTPs, Magic Links & Routing
Build a production-grade transactional email pipeline for AI apps: OTP delivery, magic link signing, notification routing, and deliverability mechanics explained.
The firewall between your AI agent and your sending reputation.
The scary part of letting an AI agent send email isn't a typo — it's that a bad loop, a poisoned input, or one abusive tenant can get your whole domain flagged as a spammer. Mails.ai is built as a firewall for exactly that: a reputation classifier and suppression check run before any send leaves, a complaint cron auto-suspends senders at 0.3% (before AWS SES's 0.5% threshold trips), reputation is isolated per agent and per workspace, and inbound is injection-scanned. Cold outreach is explicitly not a supported use case.
AI Email Automation for Developers: Triggers, Routing & Agent Actions
A technical guide to AI email automation: transactional triggers, inbound routing pipelines, and agent actions — with code patterns and architecture advice for developers.
AI Email API: Give Your AI Agent Its Own Email Address
Learn how to provision a dedicated email address for your AI agent using DNS, SMTP, and inbound webhooks. Covers addressing, authentication, and thread management.
Giving Your AI Agent an Inbox: Routing, Parsing & Webhooks
Learn how to give your AI agent a real inbox: DNS routing, MIME parsing, webhook delivery, and idempotency patterns for production systems.
Email Automation AI: Building Autonomous Agent Email Pipelines
A technical guide to email automation AI for developers: how autonomous AI agents send, receive, classify, and act on email using purpose-built API infrastructure.
Sending Transactional Email from AI Agents: OTPs, Links, Notifications
Learn how AI agents should send OTPs, magic links, and notifications with correct headers, idempotency keys, rate limits, and deliverability controls.
Mails.ai vs AgentMail: Email API for AI Agents
Mails.ai vs AgentMail compared on architecture, pricing, MCP support, inbound parsing, and deliverability for AI agent email workflows.
Parsing Email Attachments for LLM Ingestion
A technical guide to extracting, normalizing, and feeding email attachments into LLMs — covering MIME parsing, PDF extraction, OCR, and chunking strategies.
Transactional vs AI Agent Email: Architectural Differences
Deep dive into the core architectural differences between transactional email and AI agent email — threading, state, inbound parsing, and deliverability.
Inbound Email Processing for AI Agents: Classification, Routing, Actions
How AI agents classify, route, and act on inbound email: parsing raw MIME, intent classification, routing logic, and triggering deterministic actions reliably.
RFC-Compliant Email Replies from AI Agents
Learn how AI agents can compose RFC 5322-compliant email replies with correct threading headers, MIME structure, and quoting conventions.
Idempotent Email Sending for AI Agents: Patterns & Code
Stop duplicate sends in AI agent workflows. Covers idempotency keys, deduplication logic, and retry handling with mails.ai. Copy-paste code included.
How AI Agents Should Handle Email Replies
A technical guide to threading, reply detection, context management, and response generation for AI agents that send and receive email.
Building an Email-Driven Agent Workflow
Learn how to build production-grade email-driven agent workflows: inbound parsing, state machines, threading, tool dispatch, and deliverability for automated senders.
Structured Reply Events for Email Agents
Learn how to design structured reply events so your email agents can parse, route, and act on inbound replies with precision — covering schemas, threading, and idempotency.
Email API for AI Agents: Architecture & Provider Guide
Compare email API providers for AI agents. Covers MCP support, inbound parsing, deliverability, and architecture — with a clear recommendation for agent builders.
How to Build an MCP Email Server for AI Agents
Learn how to build an MCP email server that lets AI agents send, receive, and parse email via the Model Context Protocol — with real code and architecture.
Webhook-Based Inbound Email Processing for AI Agents
Learn how to build reliable webhook-based inbound email pipelines for AI agents — parsing, routing, threading, and handling edge cases at scale.
Transactional vs Agent Email Architecture
Learn the core architectural differences between transactional and agent email systems—covering SMTP flows, inbound parsing, threading, webhooks, and MCP integration.
Structured reply events — why your agent should never read raw email
Most email APIs hand your agent a string body. Mails.ai parses every inbound into a structured reply event — injection score and sender reputation on every event, opt-in classification for intent, entities, and urgency — so your code reads against a structured object, not raw bytes.
Prompt injection in inbound email is a real RCE class. Here's how mails.ai scans for it.
Prompt injection in agent runtimes is a tracked vulnerability class — Microsoft Security Response Center publishes AI-security advisories, OWASP catalogues it as LLM01. The vulnerability is structural: any agent that reads raw inbound text is exposed. Mails.ai runs a six-category scanner on every inbound before the structured reply event reaches your code, and flags high-confidence attacks (`quarantined`) so your agent skips them.
Per-event metered pricing: why monthly tiers force over-commit
Resend wants $20/month whether your agent sends 0 or 50,000 emails. Postmark wants $50. Agent traffic is bursty by nature — quiet days and incident spikes — so monthly tiers structurally force over-commit. Per-event metered pricing aligns cost to what you actually use, and incumbents cannot match without rebuilding their economics.
MCP-native email — `from mails import agent` becomes the default agent comms primitive
MCP collapsed N runtimes × M SDKs into one server that every runtime can use. Mails.ai shipped MCP-native from day one — drop a JSON snippet into your runtime config and your agent gets send, on_reply, list_threads, and get_reputation tools automatically.
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$ npm install @mailsai/sdk