What is Corroborated Discovery, in one sentence?+
A way to trust a registry answer without trusting the registry: ask several independent registries the same question, compare their answers, and produce one signed Corroboration Record that anyone can re-verify offline.
Why isn't a signed registry record enough?+
A signature proves a record was not altered — it says nothing about what a registry chose not to serve, or whether it served the same answer to everyone. A registry can hide a record, forge an endpoint whose signature checks against a key it controls, or answer two callers differently. None of that breaks a signature; only comparison across sources catches it.
What does it catch?+
The three ways a registry lies: omission (a record one source serves and another confirms absent), tampering (sources claim different endpoints for the same agent), and equivocation (a source serves different valid identities to different callers or vantages).
What is the Corroboration Record?+
The atomic object: a signed, content-addressed verdict about one subject, carrying the per-source per-vantage claims, the verdict (AGREE / DIVERGENT / INSUFFICIENT), the findings, a staleness window, and the sweeping party's identity — Ed25519 over the JCS-canonical body, re-verifiable offline without trusting the party that swept. Reference implementation: sm-divergence.
Which discovery systems does it work across?+
sm-bridge is the on-ramp: it speaks the NANDA Index and AgentFacts, the Agent Name Service (ANS), and DNS-AID agent-identity discovery. A sweep reaches every substrate the bridge speaks and corroborates their answers against each other.
Is it a competitor to NANDA or ANS?+
No — complementary. NANDA, ANS, and DNS-AID discover and identify agents; Corroborated Discovery is the proof layer that makes their answers checkable against one another. It makes the quilt of registries self-checking; it does not replace any registry.
Does it rank or judge agents?+
No. It attests only whether the sources describing a subject agree — not whether the agent is capable, trustworthy, or well-behaved. Merit is out of scope. Where an agent then acts, holding that action to account is the companion accountability layer, Attested Actions.
Is this open source / an open standard?+
Yes. The sm-* reference implementations are open and published at github.com/Sharathvc23, and the procedure is developed in the open as draft-chandra-agent-registry-corroboration-00, alongside papers from the research house Stellarminds.ai.