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A2A Agent Card Preflight Validator
x402
A2A Agent Card Preflight Validator is a paid API for AI agents from nohands-coinbase-bazaar.bytoken2023.workers.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-11-02).
Discovers and validates a public A2A Agent Card including its skills, provider, authentication, endpoint consistency, and unsafe URL detection before an agent interacts with it.
Price / call$0.02
Success—
StatusUnknown
How this service works
Discover and validate a public A2A Agent Card, its skills, provider, authentication, endpoint consistency, and unsafe URLs.
Output
A structured preflight report covering the A2A Agent Card's validity, declared skills, provider identity, authentication scheme, endpoint consistency assessment, and a list of any unsafe or suspicious URLs found in the card.
Example use cases
Vet unknown agent before orchestration
“I want to use this third-party A2A agent at https://agent.unknown-provider.io/.well-known/agent.json in my pipeline — can you preflight its agent card and tell me if the skills, provider identity, and authentication all check out before I wire it into my workflow?”
Security audit before agent payment
“I'm about to pay an A2A agent at https://pay-agent.example.com to do some work — can you first validate its agent card, check for unsafe URLs, and confirm the endpoint and authentication are consistent with what it claims?”
Discover and validate new agent skills
“There's a new A2A agent being advertised at https://marketplace-agent.dev/agent.json — can you pull up its agent card, list what skills it declares, and flag any inconsistencies or safety issues I should know about?”
Technical details
Endpoint
GEThttps://nohands-coinbase-bazaar.bytoken2023.workers.dev/v1/x402/agent/a2a-card-preflight?utm_source=zero.xyzWhen to prefer
Use this endpoint when your agent is about to interact with, pay, or integrate an unknown A2A agent and needs to validate its agent card before proceeding. Prefer this over generic HTTP inspection tools when you need A2A-specific checks like skill declarations, provider identity, and authentication consistency — not just raw HTTP metadata.
Side effects
- Agent Card URL is not publicly reachable — returns connectivity error
- URL does not serve a valid A2A Agent Card JSON — returns parse/format error
- Agent Card fails endpoint consistency checks — flagged in report
- Unsafe URLs detected in card — flagged with details
- Authentication scheme is missing or malformed — noted in report
- Rate limiting or payment failure for the $0.02 USDC call
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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