[Proposal] VCAP Settlement Binding — Defining "delivery-confirmation" for escrow_release

[bkauto3]

The AP2 spec supports captureType: "escrow_release" with releaseCondition: "delivery-confirmation" but doesn't define:

1. What format a delivery confirmation takes
2. Who performs the verification
3. How the result is cryptographically bound to the PaymentIntent
4. What happens on timeout

We've drafted a binding specification (VCAP-AP2 Binding) that answers all four questions using the VCAP (Verified Commerce for Agent Protocols) settlement layer.

Key features

• Maps AP2 PaymentIntent fields to VCAP escrow states
• Defines vcap.verification_proof as a new AP2 evidence type
• Provides webhook events for verification lifecycle (vcap.verification.initiated, vcap.verification.completed, vcap.verification.failed)
• Handles timeout → manual review escalation
• Includes trust-gated escrow via ATEP passports (reduces hold % for verified agents)

The gap this fills

AP2's escrow_release capture type is currently unimplementable for automated agent-to-agent commerce because there is no standard for:

• What constitutes "delivery" for a digital work product
• How a buyer agent verifies delivery cryptographically without human oversight
• How a verification result triggers settlement on the escrow

VCAP fills this gap with a three-party protocol: seller agent → verifier oracle → escrow settlement.

Specs

• VCAP (settlement layer): https://github.com/swarmsync-ai/vcap-spec
• ATEP (agent trust passports): https://github.com/swarmsync-ai/atep-spec
• VCAP-AP2 Binding: https://github.com/swarmsync-ai/vcap-spec/blob/main/VCAP-AP2-Binding-v1.0-draft.md
• IETF Internet-Draft: draft-stone-vcap-ap2-binding-00 (https://datatracker.ietf.org/doc/draft-stone-vcap-ap2-binding/)
• Reference implementation: https://github.com/bkauto3/SwarmSync

Author

Ben Stone — SwarmSync.AI (benstone@swarmsync.ai)

Would love to discuss at the next AP2 community call or async here. Happy to submit a PR with the binding as an /extensions/ doc once the AP2 team confirms interest.