TopSend - $20 Unlimited Email API for AI Agents

TL;DR

TL;DR: TopSend offers unlimited email marketing at a flat $20/month with a full REST API and SDKs designed for developer and AI agent workflows.

Source and Accuracy Notes

⚠️ This section is MANDATORY. All links must be verified from actual source, not guessed.

• Project page: topsend.com — verified June 2026
• Documentation: topsend.com/developers — verified June 2026
• Pricing page: topsend.com/pricing — verified June 2026
• HN launch thread: news.ycombinator.com/item?id=47505076 — verified June 2026

What Is TopSend?

TopSend is an email marketing platform built around a simple premise: unlimited emails for a flat $20/month. Where providers like Mailchimp and Klaviyo charge per-contact or per-email, TopSend includes everything — campaigns, transactional emails, contact lists, automations, and API access — under one price.

The product launched on HN in June 2026 and won Best in Show at Jason Calacanis’s LaunchFest 2026. The HN author, Nick Jarecki, framed the pitch directly: existing platforms charge “metered” rates that punish growth.

The developer documentation specifically calls out coding agents as a target use case — agents that need to send email as part of automated workflows.

API Overview

TopSend exposes a REST API covering the full email marketing lifecycle:

• Campaigns — create, schedule, and send email campaigns
• Transactional emails — single-send emails triggered by events
• Contacts and lists — management and segmentation
• Automations — triggered email flows
• Tracking — open rates, clicks, and revenue attribution

The API documentation is at topsend.com/developers. Code examples are available for common languages.

Pricing Model

The entire platform operates on a single tier:

| Feature | Included | |---|---| | Emails | Unlimited | | Contacts | Unlimited | | Automation flows | Unlimited | | Templates | Unlimited | | API access | Yes | | Revenue tracking | Yes | | A/B testing | Yes | | Custom domain | Yes | | Monthly cost | $20 |

No per-contact charges. No tiered send limits. No feature gating.

AI Agent Integration

The documentation explicitly describes the API as “Built for developers and coding agents.” This means:

• Machine-readable responses for downstream parsing
• Webhook support for event-driven agent workflows
• Structured contact management for agent-maintained contact lists
• Transactional send endpoints suitable for embedding in agent loops

An agent that needs to send email — a lead nurturing flow, a notification from a monitoring pipeline, a digest to end users — can call the TopSend API directly without managing SMTP credentials or deliverability infrastructure.

Practical Evaluation Checklist

• [ ] Read the API docs at topsend.com/developers
• [ ] Test the free tier (if available) or $20 trial
• [ ] Verify custom domain DKIM/SPF setup for deliverability
• [ ] Check webhook retry behavior for production agent use
• [ ] Confirm rate limits on burst sends

FAQ

Q: How does TopSend compare to SendGrid or Mailgun for transactional email? A: SendGrid and Mailgun focus on transactional send-only APIs. TopSend combines transactional email with a full marketing platform — contacts, campaigns, automations — under one API and one price. If you only need transactional send, those alternatives may be narrower. If you need both transactional and marketing email, TopSend’s unified model removes the need to stitch two services together.

Q: Does TopSend have a free tier? A: The HN launch mentions a free tier for small lists, but the primary model is $20/month unlimited. Check the pricing page for current free tier availability.

Q: Is there an official SDK? A: The developer docs mention SDKs but the exact languages are not verified here. Check topsend.com/developers for the current SDK list.

Q: What about deliverability and spam filtering? A: The HN author does not address this in the launch post. For production use, verify SPF/DKIM setup, check inbox placement rates against your specific list, and consider warming up new sending domains before high-volume campaigns.

Conclusion

TopSend’s value proposition is straightforward: flat-rate pricing in a space where competitors meter every contact. The explicit developer and AI agent focus in the API documentation makes it a candidate for anyone building automated email workflows — particularly agents that need marketing-grade email capability without managing separate SMTP infrastructure.

The $20/month price point is compelling if the deliverability holds up. For developer workflows where email is one piece of a larger automation pipeline, the API-first design and webhook support are worth evaluating against more established players like SendGrid or Postmark.

Source: TopSend launch on HN (news.ycombinator.com/item?id=47505076), verified June 2026.