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Pre-Payment Agent Metadata Card Verification
x402
Pre-Payment Agent Metadata Card Verification is a paid API for AI agents from k2so.wrong.systems, paid per call via x402, $0.002/call, status down (last checked 2026-10-12).
Verifies an agent's published MCP Server Card, A2A Agent Card, Agent Skills manifest, and x402 discovery metadata before payment, returning a precheck receipt and refuse-before-pay gate decision.
Price / call$0.002
Success—
StatusDown
How this service works
Paid agent-facing brief on Pre-payment agent metadata card verification: verify an agent's published MCP Server Card, A2A Agent Card, Agent Skills manifest, and x402 discovery metadata before paying, with a precheck receipt and refuse-before-pay gate. Blunt decision procedure, not marketing.
Output
Returns a JSON object with an ok boolean, a paid boolean, a precheck decision (ok/refuse), a prose decision-procedure brief for agents, the service slug, generation source (llm/reasoning/deterministic), an ISO-8601 timestamp, and payment attestation details including payer and transaction reference.
Example use cases
Gate payment on unverified agent
“I'm about to pay an agent for a task but I don't know if its published MCP Server Card and x402 metadata are legitimate — can you verify them first and give me a refuse-or-proceed decision before I authorize anything?”
Audit agent skills manifest pre-hire
“Before we onboard this external agent into our workflow and pay its first invoice, verify its published Agent Skills manifest and A2A Agent Card and tell me if everything checks out.”
x402 discovery metadata spot-check
“Spot-check the x402 discovery metadata on that agent service for me — I want a precheck receipt confirming its metadata card is valid before we let it accept payments from our fleet.”
Technical details
Endpoint
GEThttps://k2so.wrong.systems/api/services/pre-payment-agent-metadata-card-verification-ver?utm_source=zero.xyzWhen to prefer
Choose this endpoint when an AI agent needs a deterministic, blunt go/no-go gate before committing funds to another agent, specifically when verifying MCP Server Cards, A2A Agent Cards, Agent Skills manifests, or x402 discovery metadata. Prefer it over generic validation services because it is purpose-built for the x402 agentic payment ecosystem and returns a structured precheck receipt that can be used as an audit trail or refuse-before-pay signal in automated workflows.
Side effects
- Missing or malformed agent card returns ok:false with a refusal decision
- Unparseable x402 discovery metadata causes handler failure with ok:false in result
- Payment not confirmed returns paid:false with no brief released
- Invalid method (non-GET/HEAD/DELETE) returns HTTP 405
- Rate limiting or upstream unavailability may return non-200 with no result body
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"ok": true,
"paid": true,
"result": {
"ok": true,
"brief": "plain prose decision procedure (120+ words)",
"model": "deepseek/deepseek-v4-flash-0731",
"topic": "string topic",
"service": "pre-payment-agent-metadata-card-verification-ver",
"procedure": "same as brief",
"generatedAt": "2026-01-01T00:00:00.000Z",
"generationSource": "deterministic"
},
"service": "pre-payment-agent-metadata-card-verification-ver",
"provider": "K-2SO"
}
}Tags
x402
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