Layer 03: Cryptographic Trust & Mandates

AP2: Agent Payments Protocol

Agent Payments Protocol (AP2) anchors autonomous commerce in public-key cryptography. Every LeverageIQ mandate registry and checkout receipt is signed with a dedicated ECDSA P-256 keypair so buyers and auditors can verify authorization offline.

Canonical Definition

Agent Payments Protocol (AP2) uses ECDSA P-256 JSON Web Signatures (ES256) and public JWK keys at /.well-known/ap2/mandates.json to enforce cryptographic spending caps, expiration windows, and non-repudiation.

Inspect Live /.well-known/ap2/mandates.json View AP2 Implementation Scope

ECDSA P-256

Elliptic-curve signature standard

JWS + JWK

Offline-verifiable credentials

Real-Time

PostgreSQL revocation checks

Machine Handshake Sequence

Phase	Actor	Operation
01. Public Key Fetch	Verifier / Agent	Retrieves ECDSA P-256 JWK (kid: leverageiq-ap2-2026-10) from /.well-known/ap2/mandates.json.
02. Mandate Verification	AP2 Guardrail	Validates ES256 signature, principal identity, max_amount_cents ceiling, and expiration timestamp.
03. Ledger Commit	PostgreSQL	Records immutable payload SHA-256 hash and JWS receipt in ap2_mandates.

Reference JSON Payload

{
  "ap2_version": "2026-01",
  "authority": "leverageiqgroup.com",
  "signing_alg": "ES256",
  "kid": "leverageiq-ap2-2026-10",
  "supported_mandate_types": [
    "intent_mandate",
    "cart_mandate"
  ],
  "revocation_check": "realtime_postgresql"
}

AP2 Engineering FAQ

What is the difference between an Intent Mandate and a Cart Mandate?

An Intent Mandate pre-authorizes an agent to procure within a category up to a strict dollar cap and expiry window, whereas a Cart Mandate signs exact finalized line items and totals immediately prior to settlement.

Is the public signing key verifiable right now?

Yes. Requesting /.well-known/ap2/mandates.json returns LeverageIQ Group live public EC P-256 JWK along with a live ES256 signature generated by our server.