Artifact Lifecycle
MPCP artifacts flow through a defined lifecycle from policy evaluation to settlement verification.
Pipeline
Fleet Policy
↓
PolicyGrant
↓
SignedBudgetAuthorization (SBA)
↓
Trust Gateway
↓
XRPL Settlement → Receipt (txHash)
Each artifact constrains the next. Downstream artifacts must be subsets of upstream constraints.
Artifact Roles
| Artifact | Issued By | Purpose |
|---|---|---|
| PolicyGrant | Fleet/service policy | Initial permission envelope; rails, assets, caps |
| SBA | Vehicle wallet | Session-level spending envelope |
| Trust Gateway | Gateway operator | Verifies PolicyGrant + SBA, submits XRPL transaction |
| Receipt | XRPL / gateway | txHash confirming on-chain settlement |
Typical Lifecycle
- Pre-session — PolicyGrant issued and stored (fleet backend, vehicle wallet)
- Session entry — Vehicle loads PolicyGrant, issues SBA
- Payment request — Service requests payment; vehicle presents SBA
- Verification — Trust Gateway verifies PolicyGrant and SBA chain
- Settlement — Gateway submits XRPL transaction
- Receipt — Gateway returns
txHash; operator reconciles against SBA
Storage
Artifacts may be stored in:
- Fleet backend — Authoritative PolicyGrant; audit logs
- Vehicle wallet — Operational PolicyGrant, SBA, SPA, receipts
- Service provider — Received authorizations, verification results, receipts
- Settlement rail — Transaction record (authoritative)
See Also
- Reference Flow — End-to-end EV charging scenario with timeline
- Protocol specs — Full artifact specifications