What is Agent Commerce Kit (ACK)?

Agent Commerce Kit is an open specification from Catena Labs that defines the data model for AI-agent commercial agreements: agent identity (DID-based), terms of service, payment authorization, and transaction records. It is a schema and protocol spec, not a hosted service.

How does MnemoPay relate to ACK?

MnemoPay is a runtime that produces and records what ACK specifies — agent identity (we use the same DID format), signed transaction records (Ed25519, Merkle-chained), and policy-versioned payment authorization. We treat ACK as a target export format alongside our native EU AI Act Article 12 audit bundles.

Is ACK a competitor to MnemoPay?

No — ACK is a specification. MnemoPay is an implementation that can emit ACK-compatible records. They sit at different points in the stack. A team adopting ACK as their canonical record format can use MnemoPay as the production system that writes those records.

Does MnemoPay support exporting to ACK format?

Roadmap. The MnemoPay audit chain stores all the fields ACK requires; the export adapter is a translation function. We ship it on demand when an integrator asks. Today the canonical export format is the EU AI Act Article 12 bundle.

When should I care about ACK?

Care about ACK when you need to interoperate with other agent platforms that have committed to the spec. Care about MnemoPay when you need a working implementation that records signed receipts, runs FICO, holds escrow, and produces compliance evidence. The two are not in conflict.

Comparison · 2026

MnemoPay vs Agent Commerce Kit

ACK is a spec for agent commercial agreements. MnemoPay is the runtime that produces what ACK specifies. They are complementary.

tl;dr

Agent Commerce Kit (ACK) from Catena Labs defines the data schema for agent commercial agreements — DID-based identity, ToS, payment auth, transaction records.

MnemoPay is a running implementation that produces those records — Ed25519-signed, Merkle-chained, with agent FICO + escrow + HITL approval + Article 12 audit bundles on top.

ACK is the schema. MnemoPay is the system that fills it.

Feature compare

Capability	ACK (spec)	MnemoPay (runtime)
Type	Open specification	SDK + hosted service
Identity	DID-based (defines schema)	DID-based (compatible)
Transaction records	Defines format	Writes Ed25519-signed, Merkle-chained
Payment authorization	Defines schema	FiscalGate enforces budget + HITL
Agent FICO	Out of scope	Yes — 300-850, payment + behavior weighted
Escrow	Out of scope	Yes — built-in dispute window
EU AI Act Article 12 bundles	Out of scope	Yes — exportable, Merkle-verified
Money rails	Rail-agnostic spec	Stripe, Paystack, Lightning, x402, AP2
ACK export	—	Roadmap (on-demand)
License	Open spec	Apache 2.0 SDK
Install	Reference impls	`npm install @mnemopay/sdk`

When to use which

Use ACK alone

You are building from scratch and need a vendor-neutral schema as your canonical record format. You will write your own runtime.

Use MnemoPay

You need a working runtime today. Need FICO. Need escrow. Need Article 12 bundles. Want multi-rail. Want production-grade Ed25519 + Merkle infrastructure that has run 14.5M+ ops.

Also see

npm install @mnemopay/sdk

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