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Agent Trust Lookup – Verify Signed Request
x402
Agent Trust Lookup – Verify Signed Request is a paid API for AI agents from agent-trust.agent-utils.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).
Verifies the cryptographic signature on an incoming agent request, checking the signing key against a published agent-card directory to confirm the agent's identity is legitimate.
Price / call$0.005
Success—
StatusUnknown
How this service works
Know your agent before you serve it: wallet history and micro-payment behaviour on Base, ERC-8004 identity and feedback, Web Bot Auth and agent-card presence on a domain, and signed-request verification. Pay per call over x402, no API key.
Output
Returns a JSON object with: the agent's URL, the key ID used to sign the request, a boolean indicating whether the signature is valid, a reason field (null if valid, error string if invalid), a checkedAt ISO timestamp, and the count of public keys found in the agent's directory listing.
Example use cases
Gate API access for inbound agents
“An AI agent just hit my endpoint and included some signed headers — can you verify those headers and tell me if the agent's signature is valid and its key is in the public directory before I let it through?”
Debug a failed agent handshake
“My service rejected an agent request but I'm not sure why — can you run the signed headers through the trust verifier and tell me the reason the signature failed and how many directory keys were found for that agent?”
Audit trail for agent interactions
“I want to log which AI agents are making verified calls to my platform — can you verify this request's signed headers and return the agent URL, key ID, and timestamp so I can record it?”
Technical details
Endpoint
POSThttps://agent-trust.agent-utils.workers.dev/v1/verify-requestWhen to prefer
Use this endpoint when you need to cryptographically authenticate an inbound AI agent request by verifying its signed HTTP headers against its publicly hosted agent card or Web Bot Auth document. Prefer this over manual key management when you want a pay-per-call, keyless approach to agent authentication on Base-integrated infrastructure, especially when ERC-8004 identity signals and on-chain wallet history are also relevant to your trust decision.
Side effects
- Invalid or malformed headers cause valid=false with a descriptive reason string
- Agent domain has no agent card or Web Bot Auth file, resulting in directoryKeys=0 and valid=false
- Signature mismatch between provided key and directory keys returns valid=false
- Missing headers field in request body causes a 400-level error
- Payment not fulfilled via x402 returns a 402 Payment Required response
- Network timeout fetching remote agent card returns an error reason
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| headers | string |
Output
Schema · Response
{
"type": "json",
"example": {
"agent": "https://agent.example",
"keyid": "abc",
"valid": true,
"reason": null,
"checkedAt": "2026-09-06T21:00:00.000Z",
"directoryKeys": 2
}
}Tags
x402
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