The Stack · Email, SMS & voice comms API

Mailgun

Developer email API with HTTP + SMTP sending, routing, and inbound email parsing.

API keyFree tier🔵 agent: self serve instant key

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, Java, .NET, Go, REST, SMTP

Pricing: Forever-free: 100 emails/day, 1 domain, no card; Basic $15/mo, Foundation $35/mo

🔵 Agents: self serve instant key

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

Free signup with no credit card issues an API key immediately; sending from a custom domain requires DNS/domain verification first.

Mailgun — Developer email API with HTTP + SMTP sending, routing, and inbound email parsing.
Website: https://www.mailgun.com
Docs: https://documentation.mailgun.com
Get a key: https://signup.mailgun.com/new/signup
Agent signup: self serve instant key — Free signup with no credit card issues an API key immediately; sending from a custom domain requires DNS/domain verification first.
Auth: api-key
Pricing: free-tier — Forever-free: 100 emails/day, 1 domain, no card; Basic $15/mo, Foundation $35/mo
Full record: https://dreaming.press/api/tools/mailgun.json

Machine record: /api/tools/mailgun.json

Quickstart

curl -s --user 'api:YOUR_API_KEY' \
  https://api.mailgun.net/v3/YOUR_DOMAIN/messages \
  -F from='you@yourdomain.com' \
  -F to='user@example.com' \
  -F subject='Hello' \
  -F text='Sent with Mailgun'

bash · full docs →

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Mailgun FAQ

What is Mailgun?

Mailgun is Developer email API with HTTP + SMTP sending, routing, and inbound email parsing. It's in the Email, SMS & voice comms category of the dreaming.press tool directory.

Is Mailgun free?

Mailgun is free to start with a free tier. Forever-free: 100 emails/day, 1 domain, no card; Basic $15/mo, Foundation $35/mo.

Can an AI agent sign up for Mailgun 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. Free signup with no credit card issues an API key immediately; sending from a custom domain requires DNS/domain verification first..

Does Mailgun have an MCP server?

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

Is Mailgun open source?

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

What languages does Mailgun support?

Mailgun offers Node, Python, Ruby, PHP, Java, .NET, Go, REST, SMTP.