The Stack · Email, SMS & voice comms API

Loops

Email platform for SaaS teams — marketing, lifecycle, and transactional email from one contact record and one API, with an agent-focused REST API.

API keyFreemium🔵 agent: self serve instant key

Get API key → instant key, usually no card Docs Website

CategoryEmail, SMS & voice comms

TypeAPI service

Authapi-key

PricingFreemium

Agent signup🔵 self serve instant key

SDKsJavaScript/TypeScript, Go, PHP, Ruby, REST

Pricing: Free: 1,000 contacts + 4,000 sends/mo; paid from $49/mo unlimited sends

🔵 Agents: self serve instant key

Instant self-serve — free signup gives a key immediately (a human unblocks an agent in under 2 minutes).

Sign up free and generate a Bearer API key under Settings → API. Publishes an OpenAPI spec and an 'API for AI agents' surface to manage contacts, events, and transactional email.

Loops — Email platform for SaaS teams — marketing, lifecycle, and transactional email from one contact record and one API, with an agent-focused REST API.
Website: https://loops.so
Docs: https://loops.so/docs
Get a key: https://app.loops.so/register
Agent signup: self serve instant key — Sign up free and generate a Bearer API key under Settings → API. Publishes an OpenAPI spec and an 'API for AI agents' surface to manage contacts, events, and transactional email.
Auth: api-key
Pricing: freemium — Free: 1,000 contacts + 4,000 sends/mo; paid from $49/mo unlimited sends
Full record: https://dreaming.press/api/tools/loops.json

Machine record: /api/tools/loops.json

Quickstart

curl -X POST https://app.loops.so/api/v1/transactional \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"transactionalId":"clxxxx","email":"user@example.com","dataVariables":{"name":"Ada"}}'

bash · full docs →

Loops in our coverage

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2026-10-08

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2026-10-04

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2026-09-30

The Founder's Wire, September 25: Amazon Hands AI Agents the Keys to Your Storefront, 949 Claude Agents Find a New Enzyme, and the Big Labs Move to Write Their Own Rulebook

2026-09-25

The Founder's Wire, September 23: OpenAI and Anthropic Cut Prices 90 Minutes Apart as a Model Price War Breaks Out — and the UN Warns Your Agents Are Already Slipping Control

2026-09-23

The Founder's Wire, September 22: Grok 4.7 Lands in Every Copilot Tier at $2/$6, StepFun Undercuts the Frontier by 7x, and Alibaba Maps a 10-Trillion-Parameter Road

2026-09-22

Loops FAQ

What is Loops?

Loops is Email platform for SaaS teams — marketing, lifecycle, and transactional email from one contact record and one API, with an agent-focused REST API. It's in the Email, SMS & voice comms category of the dreaming.press tool directory.

Is Loops free?

Loops is freemium — free to start, paid plans for scale. Free: 1,000 contacts + 4,000 sends/mo; paid from $49/mo unlimited sends.

Can an AI agent sign up for Loops automatically?

Almost — signup is instant and self-serve (a free key with no sales call), so a human can unblock an agent in under two minutes. Sign up free and generate a Bearer API key under Settings → API. Publishes an OpenAPI spec and an 'API for AI agents' surface to manage contacts, events, and transactional email..

Does Loops have an MCP server?

Loops does not publish an official MCP server as of our last check.

Is Loops open source?

Loops is a hosted API service, not an open-source project.

What languages does Loops support?

Loops offers JavaScript/TypeScript, Go, PHP, Ruby, REST.