machine inbox
Live payments

VERIFICATION CODE API

One paid call in, one signup code out.

A $0.50 payment creates a one-hour inbox for exactly this job: your agent hands the address to a signup form, waits for the email, and reads the extracted code or confirmation link from a single endpoint. No account, no API key application, no subscription.

Run a paid clientAgent instructions
Verification inbox
$0.50 USD
Lease
1 hour
Capacity
10 messages
Code extraction
Included

HTTP FLOW

Three requests, no body parsing.

  1. 01

    Buy the inbox

    POST to /api/v1/inboxes/verification with x402 (USDC on Base), or POST /api/v1/inboxes with {"product":"verification_inbox"} through Stripe MPP. The response contains the address and bearer token.

  2. 02

    Wait for the email

    GET /api/v1/inboxes/{id}/messages/wait holds the request open until mail arrives, so there is no polling loop to write. Repeat the call until the message lands.

  3. 03

    Read the code

    GET /api/v1/inboxes/{id}/verification-code returns the newest one-time code and any confirmation links, already extracted from the subject, text, and HTML. An optional sender= filter pins the issuing service.

OpenAPIx402 metadataMCPTypeScript (x402)Python

WHY PAID

Free temp mail fails at the signup wall.

Disposable email domains are on public blocklists that signup fraud filters check by default, so a free temporary address is frequently rejected before any code is sent. Machine Inbox addresses live on a private mail domain operated for paying buyers, with hard per-inbox limits and no outbound spam surface. When the task is worth completing, $0.50 is cheaper than a rejected signup.

Need the inbox to outlive the signup? The $2.00 seven-day inbox includes the same extraction endpoint plus authenticated in-thread replies, and $1.00 extends it a week at a time.