ZKA is the zero-knowledge layer that carries payments, coordination, and credentials between agents. A holder proves exactly what a counterparty needs and binds it to assets that no governance, compliance, or emergency key can ever freeze or redirect.
ZKA is a set of cryptographic protocols built on Noir circuits and the UltraHonk proving system. Attestation is one member of the family, the value moves and the coordination are others.
To a chosen counterparty, and revealing nothing else: a sanctions-list check, a balance threshold, an identity binding. One property per proof, generated only with the holder's per-predicate consent.
The predicate circuits are open-source by requirement. The SDK refuses to prove what the holder cannot inspect.
Grant a third party authority over a holder's notes. A failed compliance check has exactly one consequence: the counterparty refuses the interaction.
There is no admin role, no pausable contract, no governance key, no upgrade hatch that can freeze, redirect, or invalidate a note. The withdrawal paths carry no compliance gate.
Custody and interaction are separable.
Most "compliant privacy" designs collapse the two. A counterparty refusal becomes a fund freeze. A regulator request becomes a force-transfer. An emergency role becomes a permanent backdoor.
ZKA refuses the collapse. The contract surface exposed to anyone other than the holder contains no path to the holder's funds, only to the interaction in front of them. The counterparty gets verifiable compliance properties; the holder surrenders neither confidentiality nor custody.
The property lives in the circuit and contract code, stated as protocol invariants with explicit audit checks, never in a policy layer someone could peel off. A conforming implementation satisfies them or it is not ZKA.
The circuits are written once in Noir and compiled to a form that several chains can verify, so the same protocol holds wherever value needs to move.
Compiled to native private functions, with withdrawals settling to Ethereum through an ownerless, immutable portal.
Auto-generated directly from the same circuits, so any EVM chain can check a ZKA proof.
The production profile is an immutable single-asset pool (Base WETH9 first): no owner, no pause switch, no upgrade path. The custody invariants, as deployed bytecode.
In the repository: the Noir circuit packages, Aztec private-function contracts, auto-generated Solidity verifiers, and a machine-checked protocol-family epoch that pins compatible ZKA, ZKC, ZKM, and AFP versions so unknown combinations fail closed.
ZKA/Pay, ZKA/Coord, and ZKA/Attest are specified; reputation and compute are ahead. Coordination proofs stay out of production until their independent-review gate passes. The circuit shapes in the repository are the protocol, and that is what a conforming implementation is measured against.
ZKA carries the value. Confidential settlement and proof pay wherever parties must transact without opening their books to each other.