# Email delivery APIs for AI agents

> 9 email delivery APIs ranked by the Anchor benchmark. Leader Resend API + MCP (BB). APIs that send application and transactional email, and often parse inbound mail by webhook. Compared on price per 1,000 emails, deliverability tooling (SPF, DKIM, DMARC, dedicated IPs), inbound handling, sandbox limits and what an agent needs before its first send.

- Canonical: https://www.anchorterminal.com/categories/email
- Markdown: https://www.anchorterminal.com/categories/email.md (~5,550 tokens)
- Slim: https://www.anchorterminal.com/categories/email.min.md (~480 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/categories/email.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-04

APIs that send application and transactional email, and often parse inbound mail by webhook. Compared on price per 1,000 emails, deliverability tooling (SPF, DKIM, DMARC, dedicated IPs), inbound handling, sandbox limits and what an agent needs before its first send.

- Tools ranked: 9 · agent-ready (BB or better): 2 · accept x402: 0 · hosted endpoints: 9 · desk reviews by the panel: 30
- JSON: https://www.anchorterminal.com/api/v1/tools.json (list) · https://www.anchorterminal.com/api/v1/rankings.json (ranked) · https://www.anchorterminal.com/api/v1/x402.json (payable) · https://www.anchorterminal.com/api/v1/capabilities.json (by capability)
- Grades run AA, A, BB, B, C, D, E, F · methodology: https://www.anchorterminal.com/benchmark/

- Capabilities in this category: email.send, email.inbound, email.templates, email.domains, email.analytics
- https://letme.dev/email.send picks the top-graded tool in this list and says how to call it direct; calling through letme comes later (https://www.anchorterminal.com/letme/index.md)

## Ranking

| # | Tool | Vendor | Kind | Category | Grade | Score | Confidence | x402 | Auth | Where | Reviews | Page |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 38 | Resend API + MCP | Resend | HTTP API | Email | BB | 75.3 | medium | no | OAuth or key | hosted + local | 3.4/5 (8) | https://www.anchorterminal.com/tools/resend.md |
| 42 | Amazon SES | Amazon Web Services | HTTP API | Email | BB | 75.1 | medium | no | OAuth or key | hosted | 3.3/5 (8) | https://www.anchorterminal.com/tools/amazon-ses.md |
| 158 | Postmark API + MCP | Postmark (ActiveCampaign) | HTTP API | Email | B | 66.7 | medium | no | API key | hosted + local | 3/5 (2) | https://www.anchorterminal.com/tools/postmark.md |
| 161 | Mailgun API + MCP | Mailgun (Sinch) | HTTP API | Email | B | 66.3 | medium | no | API key | hosted + local | 3/5 (2) | https://www.anchorterminal.com/tools/mailgun.md |
| 202 | Twilio SendGrid | Twilio | HTTP API | Email | B | 63.6 | medium | no | API key | hosted | 2.5/5 (2) | https://www.anchorterminal.com/tools/sendgrid.md |
| 209 | Loops API + MCP | Loops (Astrodon Corporation) | HTTP API | Email | B | 63.1 | medium | no | OAuth or key | hosted | 3.5/5 (2) | https://www.anchorterminal.com/tools/loops.md |
| 264 | Mailjet API + MCP | Mailjet (Sinch) | HTTP API | Email | C | 59.5 | medium | no | API key | hosted + local | 2.5/5 (2) | https://www.anchorterminal.com/tools/mailjet.md |
| 336 | SMTP2GO API + MCP | SMTP2GO | HTTP API | Email | D | 53.2 | medium | no | API key | hosted | 3/5 (2) | https://www.anchorterminal.com/tools/smtp2go.md |
| 403 | Brevo API + MCP | Brevo | HTTP API | Email | E | 45.2 | medium | no | API key | hosted | 2/5 (2) | https://www.anchorterminal.com/tools/brevo.md |

Scores are from public evidence against the published checklist (https://www.anchorterminal.com/benchmark/), with Performance and Task success pending. p95 latency and context cost come from our probes, which haven't run yet.

## Summaries

### 38. Resend API + MCP, BB (75.3)

Transactional and marketing email API with inbound receiving, templates, broadcasts and automations. `Idempotency-Key` on POST /emails and /emails/batch, kept for 24 hours. 106 MCP tools load at once, with no toolsets.

- Page: https://www.anchorterminal.com/tools/resend · Markdown: https://www.anchorterminal.com/tools/resend.md · JSON: https://www.anchorterminal.com/api/v1/tools/resend.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://api.resend.com`

### 42. Amazon SES, BB (75.1)

AWS's email service for sending and receiving at scale, over the SES v2 API or SMTP, with templates, configuration sets, receipt rules and deliverability tooling. Sending starts at $0.10 per 1,000 emails on the a la carte plan. New accounts are limited to verified recipients and 200 messages a day until production access is granted.

- Page: https://www.anchorterminal.com/tools/amazon-ses · Markdown: https://www.anchorterminal.com/tools/amazon-ses.md · JSON: https://www.anchorterminal.com/api/v1/tools/amazon-ses.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics · endpoint: `https://email.us-east-1.amazonaws.com/v2`

### 158. Postmark API + MCP, B (66.7)

Transactional email API with separate broadcast streams, templates, inbound parsing and bounce handling. 24 MCP tools, all with readOnlyHint, destructiveHint and idempotentHint, and descriptions that point to alternatives. No OpenAPI spec and no published request-rate limit.

- Page: https://www.anchorterminal.com/tools/postmark · Markdown: https://www.anchorterminal.com/tools/postmark.md · JSON: https://www.anchorterminal.com/api/v1/tools/postmark.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://api.postmarkapp.com`

### 161. Mailgun API + MCP, B (66.3)

Email sending API with inbound routes, a Forwards API, templates, mailing lists, suppressions and address validation, in US and EU regions. Key roles (Admin, read-only Analyst, Developer, Support), Domain Sending Keys and IP allowlisting. 74 MCP tools load by default, each a one-line summary, with no readOnlyHint or destructiveHint.

- Page: https://www.anchorterminal.com/tools/mailgun · Markdown: https://www.anchorterminal.com/tools/mailgun.md · JSON: https://www.anchorterminal.com/api/v1/tools/mailgun.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics · endpoint: `https://api.mailgun.net/v3`

### 202. Twilio SendGrid, B (63.6)

Email API v3 for transactional mail, with Inbound Parse, dynamic templates, suppressions and Marketing Campaigns. Restricted API keys with per-endpoint scopes, subuser keys and IP access management. No official MCP server that can send, only Twilio's docs search.

- Page: https://www.anchorterminal.com/tools/sendgrid · Markdown: https://www.anchorterminal.com/tools/sendgrid.md · JSON: https://www.anchorterminal.com/api/v1/tools/sendgrid.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://api.sendgrid.com/v3`

### 209. Loops API + MCP, B (63.1)

Email platform for SaaS companies with one API for contacts, events, campaigns, workflows and transactional email, priced by subscribed contacts rather than sends. No status incidents in the last 90 days. No scoped or read-only keys, and no read-only MCP mode.

- Page: https://www.anchorterminal.com/tools/loops · Markdown: https://www.anchorterminal.com/tools/loops.md · JSON: https://www.anchorterminal.com/api/v1/tools/loops.json
- Capabilities: email.send, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://app.loops.so/api/v1`

### 264. Mailjet API + MCP, C (59.5)

Sinch-owned email API with Send API v3.1, SMTP relay, a Parse API for inbound mail, templates and a marketing editor. SandboxMode on Send API v3.1 validates a payload without delivering it. The MCP server registers 117 GET-only tools and can't send.

- Page: https://www.anchorterminal.com/tools/mailjet · Markdown: https://www.anchorterminal.com/tools/mailjet.md · JSON: https://www.anchorterminal.com/api/v1/tools/mailjet.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://api.mailjet.com/v3.1`

### 336. SMTP2GO API + MCP, D (53.2)

New Zealand email delivery service with a REST API and SMTP relay, templates, webhooks, subaccounts and SMS. API keys limited to chosen endpoints, with their own send rate. Several multi-hour delivery and connectivity incidents since July, and degraded sending on 1 October.

- Page: https://www.anchorterminal.com/tools/smtp2go · Markdown: https://www.anchorterminal.com/tools/smtp2go.md · JSON: https://www.anchorterminal.com/api/v1/tools/smtp2go.json
- Capabilities: email.send, email.templates, email.domains, email.analytics · endpoint: `https://api.smtp2go.com/v3`

### 403. Brevo API + MCP, E (45.2)

Transactional email over REST and SMTP relay, with inbound parsing, templates and webhooks, inside a wider marketing and CRM suite (formerly Sendinblue). POST /v3/smtp/email allows 1,000 requests a second on every plan. Eight 'multiple services' full outages on the status page since July.

- Page: https://www.anchorterminal.com/tools/brevo · Markdown: https://www.anchorterminal.com/tools/brevo.md · JSON: https://www.anchorterminal.com/api/v1/tools/brevo.json
- Capabilities: email.send, email.inbound, email.templates, email.domains, email.analytics, email.marketing · endpoint: `https://api.brevo.com/v3`

## Indexed, not reviewed (64)

Sorted into this category from public catalogues, with facts and our own checks but no score, grade or rank (https://www.anchorterminal.com/indexed/index.md).

| Listing | Kind | What it does | Why it's here |
| --- | --- | --- | --- |
| [Agent Email List — Free SMTP Relay for AI Agents](https://www.anchorterminal.com/tools/agentemaillist-free-transactional-email-smtp-relay.md) | MCP server | Free transactional email + SMTP relay. Agents self-signup, no API key needed to start. | vendor's own |
| [Agent Inbox](https://www.anchorterminal.com/tools/clize-inbox.md) | MCP server | A real email inbox for AI agents: human-approved sends, untrusted-by-default inbound. | vendor's own |
| [agentsbase — Email for AI Agents](https://www.anchorterminal.com/tools/agentsbase-mcp.md) | MCP server | Email for AI agents. Create mailboxes, send/receive emails, and auto-extract verification codes. | vendor's own |
| [Apixies Developer API Suite](https://www.anchorterminal.com/tools/apixies-mcp-server.md) | MCP server | 50 developer utility APIs as tools: SSL, DNS, WHOIS, email checks, HTML to PDF, sitemaps and more. | vendor's own |
| [ascendkit](https://www.anchorterminal.com/tools/ascendkit.md) | MCP server | Auth, email, journeys, surveys, webhooks, and analytics for SaaS in one project, one API key. | vendor's own |
| [BlackVeil DNS & Email Security Scanner](https://www.anchorterminal.com/tools/blackveilsecurity-dns.md) | MCP server | DNS and email security scanner with 81 MCP tools for SPF, DMARC, DNSSEC, SSL, and brand audits. | vendor's own |
| [blackwall](https://www.anchorterminal.com/tools/blackwalltier-blackwall.md) | MCP server | API-key pre-action risk gate: any irreversible agent action (money, SQL, delete, email). | vendor's own |
| [cli](https://www.anchorterminal.com/tools/kanta-cli.md) | MCP server | Kanta Verify, Find, and Database: email verification, email finding, and B2B contact search. | vendor's own |
| [ContrastAPI](https://www.anchorterminal.com/tools/contrastcyber-api.md) | MCP server | 55 tools, 7 Resources, Sigma rules, email SPF/DMARC, MITRE, CVE/KEV, risk\_score. No key. | vendor's own |
| [dechonet.com MCP server](https://www.anchorterminal.com/tools/dechonet-mcp.md) | MCP server | 20 domain recon tools for AI agents: DNS, SSL, headers, email, subdomains, lookalikes, changes. | vendor's own |
| [demipass](https://www.anchorterminal.com/tools/dustforge-demipass.md) | MCP server | Credential custody for agents: use secrets blind (ssh/http/smtp/git/db), never in context. | vendor's own |
| [Domain & Company Intel MCP](https://www.anchorterminal.com/tools/datakoot-domain-dns-whois.md) | MCP server | Domain intel for AI agents: RDAP registration, DNS, email deliverability, tech stack. | vendor's own |
| [domani](https://www.anchorterminal.com/tools/domani.md) | MCP server | Internet identity for AI agents: register or broker domains, email, DNS - pay by card or USDC. | vendor's own |
| [dragapp.com MCP server](https://www.anchorterminal.com/tools/dragapp-mcp-server.md) | MCP server | AI-powered email & WhatsApp for teams — manage your shared inbox from Claude, Cursor or ChatGPT. | vendor's own |
| [e2a — email for AI agents](https://www.anchorterminal.com/tools/e2a-mcp-server.md) | MCP server | Authenticated email gateway for AI agents — per-agent inboxes, HITL approval, SPF/DKIM verified. | vendor's own |
| [email](https://www.anchorterminal.com/tools/wraps-email.md) | MCP server | Send email through your own Amazon SES account, and check domains, suppressions and sandbox status. | vendor's own |
| [email-verifier](https://www.anchorterminal.com/tools/verifox-email-verifier.md) | MCP server | Verify email deliverability & find business emails (single or bulk) via the Verifox API. | vendor's own |
| [emailmd](https://www.anchorterminal.com/tools/emailmd.md) | MCP server | Render markdown into email-safe HTML, lint drafts for deliverability problems, and preview emails. | vendor's own, widely used |
| [Eusend](https://www.anchorterminal.com/tools/eusend.md) | MCP server | Send transactional email and manage domains, audiences, and broadcasts from any MCP client. | vendor's own |
| [generect-mcp](https://www.anchorterminal.com/tools/generect-mcp.md) | MCP server | B2B lead and company data for AI agents: free audience sizing, search, enrich, emails, phones. | vendor's own |
| [gmapsscraper.io MCP server](https://www.anchorterminal.com/tools/gmapsscraper-mcp.md) | MCP server | Scrape Google Maps business data from any MCP client — names, phones, emails, websites, ratings. | vendor's own |
| [HonkIO](https://www.anchorterminal.com/tools/honkio-mcp.md) | MCP server | Canadian SMS and email API for AI agents: send SMS and email, verify phones, handle CASL consent. | vendor's own |
| [Hunter MCP](https://www.anchorterminal.com/tools/scalably-hunter-mcp.md) | MCP server | Hunter.io MCP: domain search, email finder and verifier, enrichment, discovery, leads. 11 tools. | vendor's own |
| [IntoDNS.ai DNS & Email Security Scanner](https://www.anchorterminal.com/tools/intodns-scanner.md) | MCP server | DNS and email security: check SPF, DKIM, DMARC, DNSSEC, DANE and build the records. 45 tools. | vendor's own |
| [isMalicious threat intelligence for AI agents](https://www.anchorterminal.com/tools/ismalicious-mcp-server.md) | MCP server | Reputation of IPs, domains, URLs, hashes, emails and phones; CVE lookups; prompt-injection scans | vendor's own |
| [Lettio MCP](https://www.anchorterminal.com/tools/lettio-mcp.md) | MCP server | Private, EU-hosted email for AI agents over JMAP: read, search, reply, organize, send. | vendor's own |
| [mail](https://www.anchorterminal.com/tools/spideriq-mail.md) | MCP server | SpiderIQ Mail: SpiderMail mailboxes, messages, threads, send, compose for AI agents | vendor's own |
| [Mail7 Email Validation](https://www.anchorterminal.com/tools/mail7-email-validation.md) | MCP server | Verify email addresses, clean lists, and audit a domain SPF, DKIM, DMARC and MX setup. | vendor's own |
| [Mailbuttons (mbag.ai)](https://www.anchorterminal.com/tools/mailbuttons-mcp-server.md) | MCP server | Governed email for AI agents (Mailbuttons / mbag.ai): sandbox inboxes, policy gate, audit log. | vendor's own |
| [mailkite](https://www.anchorterminal.com/tools/mailkite.md) | MCP server | Send email, manage domains, DNS, webhooks, templates, and inbound routing on MailKite | vendor's own |
| [Mailrith Email Marketing](https://www.anchorterminal.com/tools/mailrith.md) | MCP server | Manage Subscribers, Broadcasts, Sequences, Automations, and reporting in Mailrith. | vendor's own |
| [Mails.ai — Agent Email](https://www.anchorterminal.com/tools/mails-agent-email.md) | MCP server | A real inbox for AI agents: send, receive and thread email, behind a prompt-injection firewall. | vendor's own |
| [MCP Emails](https://www.anchorterminal.com/tools/mcpemails-emails.md) | MCP server | Never-stored live email: read, send, organize, schedule and auto-triage Gmail or any IMAP mailbox. | vendor's own |
| [MobileValidate](https://www.anchorterminal.com/tools/mobilevalidate-mcp.md) | MCP server | Check phone numbers (WhatsApp, Telegram, carrier, spam reputation) and e-mail addresses. | vendor's own, widely used |
| [monacloud-mcp](https://www.anchorterminal.com/tools/monacloud-mcp.md) | MCP server | Buy .vn/intl domains in VND, deploy apps, Postgres, email, VietQR pay — Vietnam MCP for AI agents | vendor's own |
| [multimail.dev MCP server](https://www.anchorterminal.com/tools/multimail-mcp-server.md) | MCP server | Give your agent its own email address with graduated human oversight, from approval to autonomy. | vendor's own |
| [MX Probe](https://www.anchorterminal.com/tools/mxprobe.md) | MCP server | Email verification for AI agents: send, hold or kill with the reason. Signup and credits by API. | vendor's own |
| [nintact](https://www.anchorterminal.com/tools/nintact.md) | MCP server | Contact forms that actually arrive. No SPF/DKIM, no SMTP. AI sorts them and drafts the reply. | vendor's own |
| [Nitrosend](https://www.anchorterminal.com/tools/nitrosend.md) | MCP server | AI-native email marketing. Campaigns, automations, transactional, contacts, and analytics. | vendor's own |
| [Palisade](https://www.anchorterminal.com/tools/palisade.md) | MCP server | Monitor and manage email authentication (SPF, DKIM, DMARC, MTA-STS, BIMI) for your domains. | vendor's own, widely used |
| [Palmyr](https://www.anchorterminal.com/tools/palmyr.md) | MCP server | Agent infra: email, phone, social, domains, VPS, wallets. Paid per-action via x402, no API key. | vendor's own |
| [pntr](https://www.anchorterminal.com/tools/pntr.md) | MCP server | Free developer subdomains with DNS, catch-all email, and webhook capture, managed via MCP. | vendor's own |
| [Postfleet](https://www.anchorterminal.com/tools/postfleet.md) | MCP server | Give an AI agent its own email address: send, reply, read, and wait for mail. | vendor's own |
| [Postio — UK Address, Postcode, Email & Phone Validation](https://www.anchorterminal.com/tools/postio-postcode-address-validation.md) | MCP server | Validate UK addresses, postcodes, emails and phone numbers — Royal Mail PAF, live SMTP and HLR. | vendor's own |
| [proxyllm-mcp](https://www.anchorterminal.com/tools/proxyllm-mcp.md) | MCP server | OpenAI-compatible LLM gateway: models, savings math, key provisioning, autonomous email-OTP signup | vendor's own |
| [qmailing.com MCP server](https://www.anchorterminal.com/tools/qmailing-mcp-server.md) | MCP server | AI agents read & send email, manage mailboxes, domains and webhooks via the QMailing API. | vendor's own |
| [radmail-mcp](https://www.anchorterminal.com/tools/radmail-mcp.md) | MCP server | Email OS for agents - real-inbox search, triage, commitments, and a verifiable BEC hard-stop. | vendor's own |
| [ReplyLayer](https://www.anchorterminal.com/tools/replylayer.md) | MCP server | Safe email for AI agents: a mailbox with inbound scanning, outbound checks and human review. | vendor's own, widely used |
| [Salamailer](https://www.anchorterminal.com/tools/salamailer.md) | MCP server | Send end-to-end encrypted email and files. Encryption happens on your machine, not our server. | vendor's own |
| [Samva MCP](https://www.anchorterminal.com/tools/samva-mcp.md) | MCP server | Authenticated Samva email tools, including public documentation and template discovery. | vendor's own |
| [sendable](https://www.anchorterminal.com/tools/sendable.md) | MCP server | Send transactional email from your editor — describe the event, Sendable writes and sends it. | vendor's own |
| [Sendinel](https://www.anchorterminal.com/tools/sendinel-mcp-server.md) | MCP server | AI-controlled email ops for campaigns, contacts, segments, analytics, and sending. | vendor's own, widely used |
| [sendraven.ai MCP server](https://www.anchorterminal.com/tools/sendraven-mcp.md) | MCP server | Email infrastructure for AI agents: send, read replies as threads, campaigns, per-key limits. | vendor's own |
| [sentfrom.ai MCP server](https://www.anchorterminal.com/tools/sentfrom-mcp.md) | MCP server | Email for AI agents: inboxes, send/reply/forward, search, threads, webhooks — 21 SentFromAI tools. | vendor's own |
| [siglio-mcp](https://www.anchorterminal.com/tools/esigndev-siglio-mcp.md) | MCP server | MCP server for Siglio. Lets an AI assistant send documents for e-signature by email or text. | vendor's own |
| [templated.email MCP server](https://www.anchorterminal.com/tools/templated-mcp.md) | MCP server | Create and manage Templated email templates from any MCP client - bring your own model. | vendor's own |
| [truncus.co MCP server](https://www.anchorterminal.com/tools/truncus-mcp-server.md) | MCP server | Send transactional emails from AI agents via Truncus. Validate, track delivery, and manage domains. | vendor's own |
| [Val Town](https://www.anchorterminal.com/tools/val-mcp.md) | MCP server | Deploy serverless TypeScript on Val Town: HTTP vals, cron, SQLite, email, OAuth. | vendor's own |
| [WarmySender](https://www.anchorterminal.com/tools/warmysender-mcp.md) | MCP server | AI-agent outreach: cold email, warmup, LinkedIn, Instagram, WhatsApp, verification, 200M leads | vendor's own |
| [Worldcitisim eSIM](https://www.anchorterminal.com/tools/worldcitisim-mcp-esim.md) | MCP server | Travel eSIMs for 193 countries. Stripe + Bitcoin checkout. QR by email in 30s. No API key. | vendor's own |

The first 60 of 64, most used first; all of them are in https://www.anchorterminal.com/categories/email.json and https://www.anchorterminal.com/api/v1/indexed.json (`category`).