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A2A Agent Card Preflight Validator
x402
A2A Agent Card Preflight Validator is a paid API for AI agents from base-agent-preflight.bytoken2023.workers.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-13).
Discovers and validates a public A2A Agent Card, checking its skills, provider identity, authentication declarations, endpoint consistency, and unsafe URLs.
Price / call$0.02
Success—
StatusUnknown
How this service works
Machine-payable service intelligence for discovering, verifying, and monitoring identity, risk, authorization, execution-preflight, and evidence APIs before autonomous agents spend.
Output
Returns a structured assessment including network and product metadata, identity and provenance details, an activity summary, and a safety assessment flagging any unsafe URLs or inconsistencies in the agent card's declared skills and authentication.
Example use cases
Example prompt
“Can you run a preflight check on the agent card at https://example-agent.com and tell me if its skills, authentication, and endpoint URLs all look safe and consistent?”
Technical details
Endpoint
GEThttps://base-agent-preflight.bytoken2023.workers.dev/v1/x402/agent/a2a-card-preflightWhen to prefer
Use this endpoint when you need to vet a public A2A agent before integrating with or paying it — especially to check skill declarations, provider identity, authentication method consistency, and whether any URLs in the card are unsafe. Prefer this over generic URL scanners when you specifically need A2A protocol-aware validation.
Side effects
- URL not reachable or returns non-200 — agent card fetch failure
- URL does not point to a valid A2A Agent Card — parse error returned
- Agent card contains malformed JSON — validation error with details
- Unsafe or non-HTTPS URLs detected in card — flagged in assessment
- Authentication declarations inconsistent with endpoint — flagged mismatch
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"network": "eip155:8453",
"product": "a2a-agent-card-preflight",
"assessment": {
"flags": [],
"risk_level": "low",
"risk_score": 0
}
}
}Tags
x402
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