Verify a postal address for deliverability (paid, flat fee)
verify_addressStandalone paid address verification — no mail is sent. Checks whether an address is deliverable and returns the standardized form (US: CASS with ZIP+4; international: per-country matching). Costs a small flat USDC fee per call via x402 (a fraction of a cent vs. mailing).
Two-step flow, like the mail rails: call WITHOUT paymentSignature to get the 402 challenge and paymentUrl (preferred: have the agent's x402 wallet pay paymentUrl in-band with the address as the JSON POST body {"address":{...}}); or sign the challenge and call again WITH paymentSignature to verify and get the result in one round trip. US addresses need line1 + (city+state or zip). International addresses need line1 + country.
Note: when mailing through PostAgent you do NOT need this tool — create_mail_quote already verifies sender and recipient for free as part of the quote.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| zip | No | ZIP or postal code | |
| city | No | ||
| name | No | Recipient/contact name (optional) | |
| line1 | Yes | Street address line 1 | |
| line2 | No | ||
| state | No | State/province/region | |
| country | No | 2-letter ISO country code. Omit or 'US' for CASS-standardized US verification; any other code runs international verification. | |
| paymentSignature | No | x402 PAYMENT-SIGNATURE header value signed against this endpoint's challenge. Omit to fetch the challenge first. |