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Envelope by Avasis.ai
Envelope by avasis.ai
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Part of Avasis.ai · OS for AI Agents

One API for everyResendPostmarkMailgunemail providerSendGridSESSESAgentMail

Route transactional email to Postmark. Bulk to SES. Automatically. One API, automatic failover, and a content quality gate that scores every send.

Start free →Read the docs
No credit cardFree plan5-min setup
request
POST /api/v1/send { "from": "hello@acme.com", "to": "user@documenso.com", "subject": "Your document is ready", "type": "transactional" }
response200 OK
{ "provider": "postmark", "status": "sent", "messageId": "msg_01hx9abc", "slopScore": 100, "slopFindings": 0 }
✓ Routed to Postmark — type: transactional✓ slopScore 100 — content clean✓ Failover ready: Resend → SES
Works with
Resend
Postmark
Mailgun
SendGrid
Amazon SES
Features

Everything you need to send at scale

Smart Routing

OTPs to Postmark. Bulk to SES. Automatically.

Set one rule. Envelope routes every email to the cheapest, fastest, or most reliable provider — and switches instantly if one goes down. No code changes.

await envelope.send({ type: 'otp' })
OTPPostmark
Fastest58ms
BulkSES
Cheapest120ms
NotifyResend
Best DX89ms
↻ Failover: Postmark → Resend → SES
Unified Analytics

One dashboard. Every provider.

Stop switching tabs between Resend, SES, and Mailgun. See deliverability, opens, and bounces across all your providers in a single view.

24,891
Sent
99.2%
Delivered
34%
Opened
Email Designer

Design beautiful emails,
no code required

Drag-and-drop editor with live preview, variable support, and one-click deploy.

Email Designer
DesktopMobile

Components

▬Header
≡Text
⬜Button
⬛Image
─Divider

Acme Inc.

Welcome, {{name}}!

We're excited to have you on board.

Get started →

Properties

Background

#3D8DFF

Text Color

#ffffff

Font size

18px

Padding

24px

Start from a template

Welcome

Onboarding

Magic Link

Auth

OTP Code

Auth

Invoice

Billing

Order

Commerce

Reset

Auth

Email Templates

Beautiful templates, ready to send

8 production-ready designs. Edit variables, preview live, deploy to any provider.

envelope
Welcome Email
Welcome EmailOnboarding
envelope
Order Confirm
Order ConfirmCommerce
envelope
Invoice Receipt
Invoice ReceiptBilling
envelope
Notification
NotificationStatus
envelope
Magic Link
Magic LinkAuth
envelope
OTP Code
OTP CodeAuth
envelope
Newsletter
NewsletterMarketing
envelope
Password Reset
Password ResetAuth
Open Email Designer →
Developer-first

Integrate in minutes

const res = await fetch('/api/v1/send', {
  method: 'POST',
  headers: { 'Authorization': 'Bearer your_api_key' },
  body: JSON.stringify({
    from: 'hello@acme.com',
    to:   'alice@example.com',
    type: 'transactional',
    template: 'welcome',
    vars: { name: 'Alice' },
  }),
})
// → routed to Postmark (58ms)
// → messageId: msg_xP9kL2
Content Quality Gate

Built in. Runs on every send.

The anti-slop gate catches AI-generated filler before it damages your sender reputation.

Before
"Unlock seamless transformation for your revolutionary workflow"
After — gate result
55/100⚠️
Blocked
Blocked patterns:
unlockrevolutionary
Warnings:
seamless
🛡️

Scores every send

No manual review needed

⚡

Sub-millisecond

Zero latency overhead

🎯

Configurable threshold

Block at score < 60, or customize

Part of

Avasis.ai — OS for AI Agents

Every Avasis product connects. Your agents get one API for email, security, analytics, and more.

Envelope

Unified email infrastructure

✓ Live

Aegis

Security & vulnerability intel

Soon

Dias

Agent analytics dashboard

Soon

Workspace

Smart agent workspace

Q3

Directory

Smart agent directory

Q3
Pricing

Simple, transparent pricing

Start free. Scale as you grow. No hidden fees.

Free

$0forever
  • 1 email provider
  • 1,000 emails/mo
  • Anti-slop scoring
  • API access
  • Community support
Start free

Starter

$29/month
  • 3 providers
  • 50,000 emails/mo
  • Automatic failover
  • Anti-slop scoring
  • 30-day analytics
  • Priority support
Get started
🚀 Most popular

Pro

$99/month
  • Unlimited providers
  • Unlimited emails
  • Automatic failover
  • MCP server
  • White-label
  • 90-day analytics
  • Priority support
Go Pro

All plans include API access, CLI, anti-slop scoring, and email designer. No setup fees.

🔥 Limited early access

Join the first 100 developers

Plans from $29/month. Start free — no credit card required.

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