eESP Agents
API-firstSince 2022

Loops

7.4/10

Modern SaaS-lifecycle ESP combining broadcasts and product loops with a clean API and agent-oriented docs.

Visit Loops ↗Read the docs ↗

Capability scores

Agent interface7.0
API & developer experience9.0
Automations7.0
Deliverability8.0
AI generation6.0

Positioning

Loops is built specifically for SaaS lifecycle email — broadcasts plus event-triggered loops — with a clean API and contact properties. It publishes agent-oriented API documentation, a strong signal for predictable agent integration.

Agent & API surface

  • Clean REST API and SDKs to manage contacts, send events, and trigger transactional emails.
  • Agent-oriented API documentation makes it predictable for agents to integrate.

Automations

  • Event-triggered loops for onboarding, lifecycle, and re-engagement.
  • Broadcasts for newsletters and announcements.

Deliverability

  • Managed sending with authentication and good defaults.
  • Simple suppression and unsubscribe handling.

Strengths

  • +Excellent middle ground between transactional and heavy marketing automation.
  • +Approachable, developer-friendly, generous free tier.

Trade-offs

  • –Less advanced segmentation than Klaviyo/Customer.io.
  • –Agent integration is conventional API rather than a broad MCP tool layer.

Best for

SaaS teams that want marketing + lifecycle + transactional in one approachable, developer-friendly tool.

Consider if

You need advanced segmentation, complex branching, or a deep MCP/agent tool layer — Loops favors simplicity.

Pricing posture

Free tier for small contact counts; paid plans scale with contacts. See loops.so/pricing.

Loops comparisons

Sources & further reading