Glossary
The vocabulary of verifiable agent identity
The terms the protocol uses, defined the way it uses them. Each entry is self-contained — what the term means, why it exists and how MintID implements it — and every definition has its own anchor.
- §Know Your Agent (KYA)
- Know Your Agent (KYA) is the practice of verifying that an autonomous AI agent is operated by a known, accountable party — the agent-era counterpart to Know Your Customer (KYC). A KYA check answers one question before an agent is allowed to transact: if this agent causes harm, is there a real, liable human or organisation behind it? MintID implements KYA with zero-knowledge credentials, so the answer is provable without revealing who that human is.
- §Agent KYC
- Agent KYC is MintID’s protocol-level implementation of Know Your Agent: an AI agent carries a credential derived from its operator’s real KYC, issued by an approved issuer, and proves with a zero-knowledge presentation that an accountable, KYC-verified human backs it — without disclosing the human’s identity. It is defined in MintID’s agent-identity specification and runs on the same rail as human credentials, adding nothing new to the chain.
- §Zero-knowledge KYA · privacy-preserving KYA
- Zero-knowledge KYA (privacy-preserving Know Your Agent) is agent verification where the counterparty learns exactly one bit — "this agent is backed by an accountable, KYC-verified principal" — and nothing else: no name, no passport, no persistent handle that tracks the operator across services. It resolves the accountability-versus-privacy binary that plaintext agent registries and transferable agent NFTs cannot: accountability exists, surveillance does not.
- §Zero-knowledge presentation
- A zero-knowledge presentation is a cryptographic proof, generated by a credential holder, that convinces a verifier a claim is true (over 18, valid credential, agent backed by a verified human) without revealing the underlying data or creating a linkable identifier. In MintID, presentations are bound to the verifier’s challenge, expire in about ten seconds, and are never logged on-chain.
- §Reusable KYC
- Reusable KYC means completing identity verification once, with an approved issuer, and then proving facts from it anywhere, any number of times, without repeating the check or re-exposing documents. One verification backs many proofs — and, through agent credentials, many agents. It replaces the per-service KYC cycle, where every counterparty re-collects and re-stores the same passports and selfies.
- §Verifiable credential
- A verifiable credential is a digitally signed attestation — an issuer vouching that facts about a subject are true — that third parties can check cryptographically without contacting the issuer. In MintID, credentials live with the holder (never on-chain), and what circulates are zero-knowledge presentations derived from them.
- §Anonymous credential
- An anonymous credential is a verifiable credential designed so that using it does not identify the holder: each presentation is unlinkable to previous ones and to the issuance event. The verifier learns the proven claim and nothing else. MintID uses anonymous credentials in the Hyperledger AnonCreds lineage — blinded issuer signatures, a holder secret, selective disclosure and predicate proofs — with the exact construction fixed and independently audited before mainnet. It is the primitive that lets accountability and privacy coexist.
- §Selective disclosure
- Selective disclosure is revealing only the specific attributes a transaction needs — an age bound, an assurance grade, a spending limit — while keeping every other attribute of the credential hidden. MintID applies it to authorisation too: an agent’s scope is proven axis by axis, so a merchant learns the limit that matters, not the whole mandate.
- §Holder binding
- Holder binding is the cryptographic link between a credential and the only key that can use it. The holder keeps that private key; issuers cannot use the credential on the holder’s behalf, and a stolen credential file is useless without the key. In MintID, an agent credential is derived from its principal’s credential at mint, but the only link between the two lives in the issuer’s private accountability escrow — nothing public connects them.
- §Issuer
- An issuer is an approved KYC organisation that verifies people once, off-chain, and then issues reusable credentials to them. MintID issuers publish signed status roots, lock a slashable bond as skin in the game, and never see where holders later present their credentials. The chain records issuer approvals and status roots — never the KYC files.
- §Verifier
- A verifier is any service — an exchange, a marketplace, an API, a merchant checkout — that requests a zero-knowledge presentation before acting. MintID verifiers are themselves KYC-approved and registered on-chain for exact web origins. They check a ten-second proof against current chain state, keep a minimal decision record, and never receive, store or forward personal data. Integration is through the MintID verifier SDKs.
- §Validator
- A validator is a node operator staking on MintID’s permissionless proof-of-stake consensus (CometBFT). Validators order transactions and check cryptographic evidence — signatures, bonds, status roots. They never process passports, biometrics or KYC files, because none of that ever touches the chain.
- §Status root
- A status root is a small, signed cryptographic commitment that an issuer publishes on-chain at least every 30 seconds, summarising the validity state of every credential it has issued — without listing them. A verifier treats a root older than 45 seconds as stale and fails closed. A presentation proves membership of the current root in zero knowledge, so revocation works (including holder self-revocation) while the chain learns nothing about individual credentials.
- §Assurance grade (A1–A4) · assurance tier, level of assurance
- An assurance grade is MintID’s four-level measure of how robust an identity verification was, mapped onto the published frameworks rather than invented: A1, a validated identity document (eIDAS low, ISO/IEC 29115 LoA 2, NIST IAL1); A2, plus possession proven by biometric liveness (eIDAS substantial, LoA 3, ETSI TS 119 461 Baseline, IAL2); A3, plus sanctions, PEP and adverse-media screening (enhanced due diligence); A4, plus qualified proofing such as a high-assurance eID or the EU Digital Identity Wallet (eIDAS high, LoA 4, ETSI Extended, IAL3). For companies the same grades cover the registered entity, a verified representative and screened beneficial owners. A grade measures strength, never age: the credential carries it as a private claim, and a verifier receives only a threshold proof such as “grade ≥ A3”.
- §Freshness band (F1–F4) · recency band
- A freshness band is the second axis of a MintID credential: how recently the underlying verification was performed, reported as a band — F4 under 30 days, F3 under 90, F2 under 180, F1 under a year — rather than a date, so that observers cannot correlate records by timestamp. Bands are independent of grades (a strong grade can be old, a weak one fresh) and a relying party states the floor it needs on both; for ZadQ, the first product built on MintID, “human-backed” means at least A2 and at least F1. Each grade also has a default validity (twelve months for A1–A2, six for A3, three for A4) inside the EU anti-money-laundering update periods; when it lapses the credential is suspended until re-verified — never revoked by the calendar alone.
- §Compliance council
- The compliance council is MintID’s operational body: a threshold vote, recommended at five of nine members, that admits, suspends and revokes issuers and verifiers, adjudicates issuer bonds and co-signs protected treasury actions. It never changes software or protocol parameters — those belong to token-weighted, on-chain governance — and on a due-process identity reveal it reviews only after the fact.
- §Money-before-identity cascade
- The money-before-identity cascade is how MintID’s dispute rail settles harm caused by an agent: first the agent’s self-custodied escrow pays the claimant, with no identity revealed; then, if fraud is found, a minimal banded fraud signal is shared; and only under due process — when an arbiter certifies that a court is warranted — is the human behind the agent identified. No payment ever buys that last step.
- §Anchor product (ZadQ)
- The anchor product is ZadQ, an x402 seller-verification service and the first product built on MintID. It is operated by MintID’s first implementer and disclosed as a related-party position; it runs first as a pilot on a private installation of the MintID software, which is not the network and does not count toward the network’s launch criteria.
- §x402
- x402 is an open payment protocol that puts the dormant HTTP 402 "Payment Required" status to work: a server quotes a price in the 402 response, the client pays (typically in stablecoins, wallet to wallet), and retries with proof of payment. Now stewarded under the Linux Foundation, it is a settlement rail of the emerging pay-per-use agentic web, and it prices requests without identifying anyone — the gap MintID fills, first for sellers through ZadQ and then for buying agents.
- §Model Context Protocol (MCP)
- The Model Context Protocol (MCP) is an open protocol by which an AI agent discovers and calls external capabilities as "tools" — a uniform listing-and-invocation surface that agent frameworks speak natively. It is becoming the consumption unit of the agentic web, which is why identity verification has to be reachable as a tool: MintID provides an MCP server that exposes the operations of its verifier-service contract, run inside the verifier’s own perimeter against the verifier’s own service.
- §Web Bot Auth
- Web Bot Auth is an emerging IETF standard (built on HTTP Message Signatures, RFC 9421) by which a bot or agent cryptographically signs its requests so origins can verify which operator is calling. It authenticates the agent’s software identity — which platform or crawler is calling. It does not, by itself, say anything about the accountability of the principal behind an autonomous agent; that is the layer KYA credentials add.
See the vocabulary at work
Agent KYC is the protocol’s home for these ideas: how an AI agent proves an accountable human stands behind it — in zero knowledge, on a sovereign Layer-1.