Show HN: GoodSender – the email API for makers and AI agents

Send emails that land in the inbox by default — permission enforced, engagement monitored, on the stack we built for the world's largest senders. 100,000 emails a month, free.

“Deliverability isn't infrastructure — it's earned. GoodSender automates the earning: permission, engagement, reputation. The way email was always supposed to work.”

Marketing email starts with permission. Every recipient confirms before you can reach them — enforced at the API. Once they're in, send away. Mailbox providers reward this. So do we.

Send a consent request to any email address. It takes ~150ms.

They click a link in a standard, high-reputation system email.

The recipient is unlocked for your API key globally.

Hit /v1/emails/send with markdown, HTML, or plain text. We render, suppress, and deliver from the high-reputation pool.

Pick a template, pass your variables, and it's in the inbox. Transactional emails are pre-cleared — no consent workflow required.

Verify a user as they turn on multi-factor authentication.

Alert users when their account is accessed from a new device.

Magic-link or one-click sign-in without a password.

Confirm a successful checkout with receipt-ready details.

One-time passcodes for 2FA and passwordless login.

We expand the catalog over time based on what customers ask for.

Permission opens the door. Engagement keeps it open. We watch every signal — opens, clicks, complaints, silences — and handle list hygiene so your sender reputation only goes up.

Opens, clicks, bounces, and complaints — tracked per recipient, aggregated into a live engagement score by our agents.

Six months without engagement triggers an automatic re-permission ping. No response? They drop off your list — not your problem.

Unsubscribes and spam complaints are suppressed instantly across your workspace. You physically cannot send to them again. Reputation: protected.

All of it lives behind a single endpoint. Pass markdown, HTML, or plain text — we handle rendering, suppression, and delivery on the shared high-reputation pool.

curl -X POST https://api.goodsender.com/v1/emails/send \
  -H "Authorization: Bearer <your-api-key>" \
  -H "Content-Type: application/json" \
  -d '{
    "emails": [
      {
        "from": { "email": "sender@example.com", "name": "Example Sender" },
        "to": [{ "email": "recipient@example.com" }],
        "subject": "Hello from GoodSender",
        "markdown_content": "## Hello from GoodSender\nYour first email is on the way."
      }
    ]
  }'

No template language. No rendering pipeline. Pass the model output directly — we handle the conversion to bulletproof email HTML.

Draft the next issue in your assistant, pick the audience, send. New subscribers get a consent request in the background — their first issue goes out the instant they confirm.

Draft the next issue and preview it right inside Claude, ChatGPT, or your terminal. Refine until it looks right — no copy-pasting between tabs.

Send to the whole list, a segment, or a fresh batch of emails. Your agent lines up the audience in plain language.

Ship now or schedule it via your assistant's task system. New subscribers get a consent request in the background — their issue goes out the moment they confirm.

2009 — our founders built SendGrid to help developers solve the problem of emails landing in spam. The cloud infrastructure shipped. The deliverability problem didn't go away. Deliverability is earned, not built.

2018 — we left the space. Years later, the core problem was still there. Senders were still fighting for the inbox.

2025 — we built Laneful: email engineers, custom IP lanes, and AI agents that monitor traffic health for the largest senders in the world. Tailored involvement that reduces ESP costs and earns top-tier deliverability at scale.

Today — GoodSender is that same playbook, automated. Permission, engagement, and reputation wired into a single API for smaller teams and AI agents.

When every recipient consented and every list is healthy, infrastructure costs collapse. We pass the savings on. 100K free / month, $1 per 100K beyond. Here's how that compares:

First 100k emails/month free — covers everything you send, transactional and marketing alike. Practically free for most businesses at any realistic volume.

Beyond your free 100k — $1 per additional 100k. No subscriptions, no surprises.

Transactional templates — MFA, New Device, Login, Order Completed, OTP — don't require permission. Catalog grows with customer demand.

swipe swipe to compare

// 100K and 1M prices verified on competitor pricing pages on 2026-04-20. SendGrid has no published 1M tier — the figure shown is the closest published one (700K = $499). 500K and 10M remain approximate. Competitor pricing may vary by plan, volume tier, and billing period.

Need enterprise-grade volume?

Add your domain, grab an API key, and send your first email — with permission and engagement built in — in under 10 minutes.