The Stack · Email, SMS & voice comms API

Resend

Developer-first transactional email API with a clean SDK, React email templates, and instant self-serve API keys.

API keyFree tier🔵 agent: self serve instant keyMCP ✓

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

CategoryEmail, SMS & voice comms

TypeAPI service

Authapi-key

PricingFree tier

Agent signup🔵 self serve instant key

SDKsNode, Python, Ruby, PHP, Go, Rust, Java, REST

MCP serveravailable →

Pricing: Free: 3,000 emails/mo (100/day); Pro from $20/mo

🔵 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 an API key immediately from the dashboard; domain verification required before sending from your own domain (or use the shared onboarding@resend.dev). API also manages domains/keys programmatically.

Resend — Developer-first transactional email API with a clean SDK, React email templates, and instant self-serve API keys.
Website: https://resend.com
Docs: https://resend.com/docs
Get a key: https://resend.com/signup
Agent signup: self serve instant key — Sign up free and generate an API key immediately from the dashboard; domain verification required before sending from your own domain (or use the shared onboarding@resend.dev). API also manages domains/keys programmatically.
Auth: api-key
MCP server: https://github.com/resend/mcp-send-email
Pricing: free-tier — Free: 3,000 emails/mo (100/day); Pro from $20/mo
Full record: https://dreaming.press/api/tools/resend.json

Machine record: /api/tools/resend.json · add its MCP server →

Quickstart

import resend

resend.api_key = "re_..."

resend.Emails.send({
    "from": "onboarding@resend.dev",
    "to": "user@example.com",
    "subject": "Hello",
    "html": "<p>Sent with Resend</p>",
})

python · full docs →

Model Context Protocol

Resend exposes an MCP server, so you can add its tools to Claude, Cursor, or any MCP client: https://github.com/resend/mcp-send-email

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Resend FAQ

What is Resend?

Resend is Developer-first transactional email API with a clean SDK, React email templates, and instant self-serve API keys. It's in the Email, SMS & voice comms category of the dreaming.press tool directory.

Is Resend free?

Resend is free to start with a free tier. Free: 3,000 emails/mo (100/day); Pro from $20/mo.

Can an AI agent sign up for Resend 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 an API key immediately from the dashboard; domain verification required before sending from your own domain (or use the shared onboarding@resend.dev). API also manages domains/keys programmatically..

Does Resend have an MCP server?

Yes — Resend offers a Model Context Protocol server, so you can add its tools to Claude, Cursor, or any MCP client: https://github.com/resend/mcp-send-email

Is Resend open source?

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

What languages does Resend support?

Resend offers Node, Python, Ruby, PHP, Go, Rust, Java, REST.