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anywaypossible.com Payment Guard
x402
anywaypossible.com Payment Guard is a paid API for AI agents from anywaypossible.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-11).
Validates an x402 HTTP 402 payment challenge before an AI agent signs it, returning a machine-readable safe-to-sign, fund, review, or reject decision.
Price / call$0.01
Success—
StatusUnknown
How this service works
Verify an x402 purchase before an AI agent signs. Validate the live HTTP 402 challenge, Base network, USDC asset, quoted price, recipient, price ceiling, buyer funding, optional gas reserve, and destination hazards, then receive a machine-readable safe-to-sign, fund, review, or reject decision. No account or API key.
Output
A machine-readable decision object indicating safe-to-sign, fund, review, or reject, along with details on the validated fields: network, asset, price, recipient, funding status, gas reserve adequacy, and any destination hazards detected.
Example use cases
Guard agent from overpaying an API
“I want you to check this x402 402 challenge before signing — my price ceiling is $0.10 USDC, the network should be Base, and the asset must be USDC. Tell me if it's safe to sign or if I should reject it.”
Verify recipient address before payment
“Before my agent pays this x402 invoice, validate that the recipient address isn't a known hazard destination and that the quoted price of $0.05 USDC matches what was agreed — give me a clear safe-to-fund or reject decision.”
Check wallet funding before approving
“Can you confirm my wallet has enough USDC and ETH for gas on Base to cover this x402 payment challenge before my agent signs anything? I want to make sure we won't fail mid-transaction.”
Technical details
Endpoint
POSThttps://anywaypossible.com/api/payment-guard?utm_source=zero.xyzWhen to prefer
Use this endpoint when an AI agent needs to autonomously decide whether to sign an x402 HTTP 402 payment challenge on the Base network using USDC, especially when safety guardrails, price ceilings, recipient verification, and funding checks are required before committing a transaction. Prefer over building custom validation logic when you need a no-account, no-API-key, one-call decision primitive.
Side effects
- Invalid or expired 402 challenge returns rejection decision
- Insufficient buyer USDC funding triggers reject or review flag
- Wrong network (non-Base) causes validation failure
- Price exceeds ceiling threshold returns reject decision
- Recipient address flagged as hazardous returns reject
- Missing required fields in the 402 challenge body returns error
- Gas reserve insufficient triggers review or reject decision
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
Reviews
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