PEAC: Policy-backed Environment for Agent Coordination

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119.

Receipt

A cryptographically signed attestation of a completed transaction or policy evaluation.

Issuer

The entity that creates and signs receipts. Identified by the iss claim.

Verifier

Any party that validates receipt signatures and claims.

Policy

A machine-readable declaration of access terms, published at /.well-known/peac.txt.

PaymentEvidence

Structured proof of payment including rail, amount, currency, and optional facilitator.

Attestation

A generic third-party claim attached to a receipt (e.g., risk assessment, compliance check).

PEAC receipts are encoded as JWS Compact Serialization (RFC 7515) with detached payload option available. The receipt MUST be transmitted via the PEAC-Receipt HTTP header.

PEAC-Receipt: <base64url(header)>.<base64url(payload)>.<base64url(signature)>

Header (REQUIRED):
{
  "alg": "EdDSA",           // MUST be EdDSA
  "typ": "peac-receipt/0.1", // MUST be this value
  "kid": "peac-2025-12"      // Key identifier
}

Payload (REQUIRED fields):
{
  "iat": 1735500000,         // Unix timestamp (seconds)
  "iss": "https://api.example.com",
  "amt": 100,                // Amount in minor units
  "cur": "USD",              // ISO 4217 currency
  "payment": {               // Payment evidence
    "rail": "x402",
    "facilitator": "daydreams"
  }
}

Agents MUST attempt to fetch policy from these locations in order:

1. /.well-known/peac.txt (primary)
2. /peac.txt (fallback)

The policy file uses YAML format with the following structure:

version: "peac-policy/0.1"
rules:
  - id: allow-licensed
    match:
      subject_type: [agent, organization]
      purpose: [train, inference]
      licensing_mode: licensed
    decision: allow
    receipts: required

  - id: allow-crawl
    match:
      purpose: [crawl, index, search]
    decision: allow

  - id: deny-unlicensed-training
    match:
      purpose: [train]
      licensing_mode: unlicensed
    decision: deny

Verifiers MUST perform these steps in order:

1. Parse JWS: Decode base64url header and payload. Reject malformed tokens.
2. Validate header: Confirm alg is “EdDSA” and typ is “peac-receipt/0.1”.
3. Fetch JWKS: Retrieve public key from issuer's /.well-known/jwks.json matching kid.
4. Verify signature: Validate Ed25519 signature over header.payload.
5. Check timestamp: Reject if iat differs from current time by more than 5 minutes.
6. Validate evidence: Ensure payment.evidence contains only JSON-safe values (no NaN, Infinity, cycles).

PEAC v0.9.21 introduces generic Attestation and Extensions types for extensible evidence attachment. v0.9.25-v0.9.27 add specialized attestation types: peac/agent-identity (v0.9.25), peac/attribution (v0.9.26), and peac/dispute (v0.9.27).

{
  "attestations": [{
    "type": "risk_assessment",
    "issued_at": 1735500000,
    "issuer": "https://risk.example.com",
    "data": {
      "score": 0.95,
      "level": "low"
    }
  }],
  "extensions": {
    "acme/tracking_id": "abc123",
    "vendor/metadata": { "key": "value" }
  }
}

PEAC v0.9.22 introduces telemetry hooks in the issue() and verify() functions with privacy-preserving modes.

import { createOtelProvider } from '@peac/telemetry-otel'

const provider = createOtelProvider({
  tracer,
  meter,
  privacyMode: 'balanced'
})

// Automatically emits spans and metrics
const { jws } = await issue({ ...claims, telemetry: provider })

• •JWS signature verification required before trusting any receipt claim
• •Key discovery via JWKS endpoints with SSRF guards and timeouts
• •No silent network fallback for offline verification (fail-closed)
• •Replay protection via nonce + timestamp validation
• •Request binding (DPoP) supported where rail adapter enables it
• •Errors mapped to RFC 9457 Problem Details (no internal details exposed)