The Stack · Email, SMS & voice comms API

Knock

Notifications infrastructure for developers — orchestrate email, push, SMS, in-app, and chat from one workflow 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

SDKsNode, Python, Ruby, Go, Elixir, PHP, .NET, Java, REST

Pricing: Free Developer tier: 10,000 messages/mo; Starter $250/mo (50k messages), then $0.005/msg

🔵 Agents: self serve instant key

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

Self-serve dashboard signup with a free 10k-message/mo tier; API keys available immediately. Only charges for messages actually sent.

Knock — Notifications infrastructure for developers — orchestrate email, push, SMS, in-app, and chat from one workflow API.
Website: https://knock.app
Docs: https://docs.knock.app
Get a key: https://dashboard.knock.app
Agent signup: self serve instant key — Self-serve dashboard signup with a free 10k-message/mo tier; API keys available immediately. Only charges for messages actually sent.
Auth: api-key
Pricing: freemium — Free Developer tier: 10,000 messages/mo; Starter $250/mo (50k messages), then $0.005/msg
Full record: https://dreaming.press/api/tools/knock.json

Machine record: /api/tools/knock.json

Quickstart

import { Knock } from "@knocklabs/node";

const knock = new Knock("sk_test_...");

await knock.workflows.trigger("new-comment", {
  recipients: ["user_1"],
  data: { comment: "Hello" },
});

javascript · full docs →

Knock in our coverage

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Knock FAQ

What is Knock?

Knock is Notifications infrastructure for developers — orchestrate email, push, SMS, in-app, and chat from one workflow API. It's in the Email, SMS & voice comms category of the dreaming.press tool directory.

Is Knock free?

Knock is freemium — free to start, paid plans for scale. Free Developer tier: 10,000 messages/mo; Starter $250/mo (50k messages), then $0.005/msg.

Can an AI agent sign up for Knock 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. Self-serve dashboard signup with a free 10k-message/mo tier; API keys available immediately. Only charges for messages actually sent..

Does Knock have an MCP server?

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

Is Knock open source?

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

What languages does Knock support?

Knock offers Node, Python, Ruby, Go, Elixir, PHP, .NET, Java, REST.