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x402 Payment Challenge Sanity Checker
x402
x402 Payment Challenge Sanity Checker is a paid API for AI agents from www.mahastrategies.com, paid per call via x402, $0.0035/call, status unknown (last checked 2026-10-16).
Validates the structure and policy fields of an x402-v2 exact-payment challenge against caller-supplied expected values for URL, EVM network, asset, payee, and maximum price — without making live requests or payments.
Price / call$0.0035
Success—
StatusUnknown
How this service works
Inspect one supplied x402-v2 exact-payment challenge against an explicit expected HTTPS resource, EVM CAIP-2 network, asset, payee and maximum price. Checks both URL declarations, structure and payment-policy fields only; no live probe, payment, facilitator verification or server-authenticity claim.
Output
Returns a structured result object containing a pass/fail validation outcome, a list of boundary violations (if any), the offer ID ('x402-challenge-sanity'), input and receipt digests for audit purposes, and the amount in base units (3500). No live network probe, payment, or facilitator verification is performed.
Example use cases
Pre-payment challenge verification
“Before my agent pays this x402 challenge, check that the payee address, EVM network (eip155:8453), asset, and max price of 0.01 USDC all match what's declared in the challenge object — don't actually pay anything, just validate the fields.”
Automated x402 policy audit
“I'm building a pipeline that receives x402 payment challenges from various APIs. Can you inspect this challenge and confirm that the URL declaration, network, and payment policy fields match my expected values for the Base mainnet USDC payee?”
Security check before agent payment authorization
“My AI agent just received an x402-v2 challenge claiming to require payment to a specific payee on eip155:1 in USDC. Can you validate the challenge structure and policy fields against my expected resource URL and payee to make sure nothing looks off before I allow the payment?”
Technical details
Endpoint
POSThttps://www.mahastrategies.com/api/v1/micro/x402-challenge-sanity?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need a fast, offline structural check of an x402-v2 payment challenge before authorizing payment — particularly when you want to verify payee, network, asset, and price policy fields match your expectations without incurring any live network request, payment, or facilitator lookup. Prefer this over manual parsing when building agents that must validate x402 headers programmatically and need an auditable digest trail.
Side effects
- Missing required fields in challenge or expected object returns a validation error
- Mismatched URL, payee, network, or asset causes boundary violations in the result
- Malformed CAIP-2 network identifier may cause parsing failure
- Invalid or non-HTTPS resource URL rejected at structure check
- Schema mismatch (wrong bodyType or method) returns HTTP-level error
- dataClass enum value outside 'public' or 'synthetic' causes rejection
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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