Public beta · Shared CLI and Web inspection core
Evidence, with boundaries.
The scanner performs static Agent Card inspection. It checks a documented subset of core fields, reviews declared settings, and verifies supported signatures under an explicit policy. It does not invoke agent tasks or test declared authentication endpoints.
What signature results mean
| Result | Meaning |
|---|---|
| Verified | Integrity verifies with the selected public key and payload profile. This does not establish a legal identity or trustworthy behavior. |
| Unsigned | No signature is present. Signing is optional in A2A and unsigned alone does not fail the default policy. |
| Does not verify | Verification failed under the selected profile. When raw JCS verifies but the v1.0.1 presence profile does not, a specific diagnostic explains that difference. |
| Not accepted | The signature or key URL does not meet the supported profile or policy. |
| Key unavailable | No usable key was resolved. This is different from proving that a signature is invalid. |
One policy, before and after deployment
The Web and CLI share rule IDs, signature handling, report schema and failure thresholds. The default threshold is high; advisory observations do not fail it. You can separately require at least one valid signature. The Web adds service-wide time and traffic budgets.
Public key URLs must share the final card’s exact HTTPS origin, including port. Explicitly supplied public JWKS is authoritative. The supported v1 signature profile applies field-presence rules based on A2A v1.0.1 before JCS serialization. Legacy shapes use JCS without signatures.
What we do not establish
A policy pass is not a safety certificate, complete A2A conformance, operator identity verification, revocation check, or a collusion verdict. An absent authentication declaration does not prove that the running service is unauthenticated. A card is a statement from its publisher, not an observation of every runtime action.
A point-in-time result
Published reports include the card retrieval time, final URL, content digest, tool and policy versions. A later deployment or key rotation may produce different evidence. There is no automatic monitoring in this release. A network failure or unavailable card produces an incomplete operation, separate from a completed policy failure.
Public beta limits
Cards and key documents are limited to 512 KiB; at most eight signatures and 32 public keys are supported. Each network retrieval has an eight-second budget. The hosted inspection has a 20-second processing budget. The initial service permits up to four concurrent inspections, 60 admissions per minute in total, and 10 per client address per minute. Use the CLI when you need a local workflow without shared service limits.
Validation and ongoing work
Controlled tests cover cryptographic, transport and policy boundaries. A bounded sample of 24 existing public card URLs produced 23 completed inspections and one 404 response on September 17, 2026. Those observations are not ecosystem failure rates or a measurement of detection accuracy. Independent SDK interoperability and broader external usability review remain ongoing work.