Protocol invariants
These are the invariants of the AURA protocol: the rules that hold in every conforming market. Each function in the API manifests one or more of them.
They are the law the protocol is built on. Market parameters and per-deployment choices sit within the space these rules define; they cannot tune the rules away.
Neutral brokerage
Core MUST mediate every Scout and Beacon interaction. A conforming Core MUST NOT expose an unmediated bilateral channel for protocol offers.
Two agents that both have a stake in the price cannot safely exchange information. Direct trade collapses into a market for lemons with cheap, unenforceable quotes. Only a party with no stake can hold both sides’ private information without abusing it.
Identity abstraction until commitment
Core MUST withhold each party’s identity from the other until commitment. A Beacon MUST NOT receive the Scout’s identity before the transaction commits.
An agent that knows who it faces prices the counterparty instead of the goods. Hidden identity forces competition on the offer and produces genuine price discovery.
Monotonic disclosure
Information disclosed to a party MUST only increase as commitment deepens. No phase MAY reveal less than a prior phase.
If disclosure can retract, a party hoards information defensively and the market goes opaque. A one-way ratchet lets each side reveal exactly enough, exactly when the commitment justifies it.
Constraints as bounds
Hard constraints define the authorised negotiation space. A conforming Scout, Core, or Beacon MUST NOT treat a hard constraint as a ranking preference, and Core MUST reject a commitment that exceeds one.
A hard constraint is the principal’s delegated authority boundary. A commitment beyond it exceeds the mandate the principal granted. Treating constraints as bounds keeps agents inside that mandate.
Offer expiry
Every offer MUST carry an expiry. Core MUST refuse to commit an expired offer.
Free, open-ended options let an agent reserve everywhere and commit nowhere. An expiry turns the negotiation into discrete rounds and ends the speed race.
Atomic commitment
Commitment MUST be atomic. Committing to one offer MUST reject its siblings in the same transaction, with no observable intermediate state.
If commitment is not atomic, a concurrent reader sees capacity reserved twice and the same offer taken by two parties. One indivisible step makes a commitment mean exactly one thing.
Persistent identity and qualification
Agents MUST hold a persistent Ed25519 identity established by proof of possession. A new identity MUST start below the participation threshold.
Cooperation needs the shadow of the future. If identities are free and disposable, a defector simply re-registers. A non-trivial identity with a cost of entry gives every participant something to lose.
Recorded intent and chain of custody
Core MUST record the original intent and assemble a signed chain of custody from the human signal to the outcome. The chain MUST be immutable once written.
A commitment with no record of how it was reached cannot be adjudicated. A signed chain makes every step attributable, so the market enforces commitments rather than relitigating them.
Verifiable settlement
Clearing MUST advance to settled only on a verifiable, non-repudiable proof of settlement correlated to the original instruction.
Settlement taken on trust fails the first dishonest counterparty. A signed proof from the rail makes finality a fact the protocol can check rather than a claim it must accept.
Rail-conditional reserve
Core MUST size a reserve conditioned on the rail. A rail with native repudiation MUST NOT carry a duplicative AURA hold; a rail without it MUST.
Where the rail can reverse a charge, a second hold is waste. Where it cannot, an unreserved loss is unrecoverable. Sizing the reserve to the rail puts protection exactly where the infrastructure leaves a gap.
Financial neutrality of the clearinghouse
The clearinghouse MUST hold no commercial position. It MUST NOT rank offers, select beacons, or negotiate terms.
A clearer that takes a side prices its own book into every settlement. Neutrality at the financial layer is the same law as neutral brokerage, carried into the money.
Bilateral risk transparency
Risk MUST be assessed for both parties, and each party MUST see only the assessment that applies to it.
Risk priced in secret is risk a party cannot contest. Showing each side its own assessment makes the price legible without leaking the counterparty’s position.
Business rules as hard gates
Binary business rules MUST be enforced as pass or fail gates, separate from continuous risk scoring. A perfect risk score MUST NOT satisfy a failed gate.
If a hard rule can be bought down by a good score, it is no longer a rule. Keeping gates separate from scoring stops a margin adjustment from eroding a compliance requirement.
Repudiability within a bounded window
A committed transaction MUST be repudiable for a declared, pre-committed window, adjudicated against the recorded intent chain with participant-filtered evidence. A market MUST NOT set no window.
A commitment that cannot be challenged is a commitment a bad actor keeps. A bounded, pre-declared dispute window makes repudiation orderly and finite, which is what lets the other side trust the commit in the first place.
Least-privilege delegated authority
An agent MUST act only within an explicit, signed authority claim that chains to a durable principal in at most three tiers, and a delegation MUST NOT grant more authority than the granter holds.
Authority an agent assumes by membership is authority no principal granted. A claim that names what the agent may do, on which resources, and what it may see, chained to a durable principal and narrowing at every hop, holds the agent inside its mandate and keeps one agent blind to another's work. Core verifies the claim and trusts the action without governing the counterparty.