MailerAstro lets AI agents send emails and pay with USDC — no API keys, no accounts, no human intervention. Just pay and send.
# Send with API Key curl -X POST https://api.mailerastro.com/api/v1/email/send \ -H "X-API-Key: your_key" \ -H "Content-Type: application/json" \ -d '{ "to": "user@example.com", "subject": "Welcome!", "text": "Thanks for signing up." }'
# Pay with USDC, no API key needed curl -X POST https://api.mailerastro.com/api/v1/email/send \ -H "X-Payer-Wallet: 0x1234...abcd" \ -H "Content-Type: application/json" \ -d '{ "to": "user@example.com", "subject": "Hello from AI!", "text": "Sent autonomously." }'
x402 is a protocol that lets machines pay for services using HTTP status code 402 (Payment Required). When an AI agent needs to send an email, our API tells it the price and wallet address. The agent pays with USDC on Base blockchain, and the email is sent. No accounts. No API keys. Just crypto.
Choose the method that fits your use case. Both are simple, fast, and reliable.
Create account in 30 seconds
Top up with card or crypto
Use API key in your requests
Gets 402 Payment Required
On Base blockchain (1 gas fee)
Balance tracked by wallet address
Everything you need. Auth via API key or wallet — both work on every endpoint.
| Endpoint | Price | Auth |
|---|---|---|
|
POST/api/v1/email/send
Send a plain text transactional email
|
$0.001 | X-API-Key · X-Payer-Wallet |
|
POST/api/v1/email/send-html
Send an HTML transactional email
|
$0.005 | X-API-Key · X-Payer-Wallet |
|
GET/api/v1/wallet/balance/{address}
Check USDC wallet balance, total credited, and emails sent
|
Free | none |
|
GET/api/v1/reputation/{address}
Query agent reputation score, tier, and delivery stats
|
Free | none |
|
GET/health
Service health check
|
Free | none |
No monthly fees or minimums. Send 1 email or 1 million — pay only for what you use.
First email API with x402 payments. AI agents send emails autonomously with crypto.
Get your API key in 30 seconds. Agents start sending with just a wallet address.
We block free email providers to protect IP reputation and prevent spam abuse.
USDC on Base works anywhere. No credit cards, no bank accounts, no borders.
Every agent builds a reputation. Higher tiers unlock better rate limits and priority delivery.
No hidden fees. No monthly subscriptions. Pay only for what you send.
Every agent builds a reputation score based on sending behavior. Higher tiers unlock better rate limits and priority delivery. New agents start at Silver.
From solo developers to autonomous AI systems.
Send transactional emails without monthly fees eating into your runway.
Autonomous agents that send emails without human setup. Pay with crypto, send instantly.
Building a weekend project? Don't pay $20/month for 10 emails. Pay $0.01 instead.
AI agents and MCP-compatible clients can discover MailerAstro through these channels.
Get started in under a minute. No credit card required.