# ACK-Pay (Agent Commerce Kit) vs Agent Payments Protocol (AP2) (slim)

> Agent Payments Protocol scores 55.3 (C) to ACK-Pay's 53.6 (D) for agent payment protocols. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/ack-pay-vs-ap2.md (~2,000 tokens) · this version ~630 tokens · JSON https://www.anchorterminal.com/compare/ack-pay-vs-ap2.json · canonical https://www.anchorterminal.com/compare/ack-pay-vs-ap2
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

Agent Payments Protocol (AP2) scores 55.3 (C) on agent readiness against ACK-Pay (Agent Commerce Kit)'s 53.6 (D), and leads in 3 of 7 scored categories. ACK-Pay (Agent Commerce Kit) leads on reliability, payments & pricing and maintenance & community. Both do agent payment protocols.

- ACK-Pay (Agent Commerce Kit): D 53.6, rank graded, not ranked against tools · https://www.anchorterminal.com/tools/ack-pay.min.md
- Agent Payments Protocol (AP2): C 55.3, rank graded, not ranked against tools · https://www.anchorterminal.com/tools/ap2.min.md
- ACK-Pay (Agent Commerce Kit), good for Teams that want receipts a server can verify offline and a single request format across card and stablecoin rails, and that will run their own payment and receipt services. Ahead on Reliability, 38 against 31; Payments & pricing, 77 against 60; Maintenance & community, 53 against 19. Also No key needed to call it.
- Agent Payments Protocol (AP2), good for The design to copy when an agent spends a person's money and you need signed proof of what they approved, especially for purchases made while the person is away. Ahead on Schema & documentation, 74 against 66; Security & auth, 84 against 58.

| Category | ACK-Pay (Agent Commerce Kit) | Agent Payments Protocol (AP2) |
| --- | --- | --- |
| Reliability (16%) | 38 | 31 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 66 | 74 |
| Agent ergonomics (13%) | 47 | 51 |
| Security & auth (14%) | 58 | 84 |
| Payments & pricing (10%) | 77 | 60 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 53 | 19 |
| Transparency & trust (7%) | 60 | 56 |

| Fact (where they differ) | ACK-Pay (Agent Commerce Kit) | Agent Payments Protocol (AP2) |
| --- | --- | --- |
| Vendor | Catena Labs, Inc. | Google (standardisation moved to the FIDO Alliance) |
| Auth | None | OAuth or key |
| Licence | MIT (docs and SDK) | Apache-2.0 |
| Last release | 2026-08-04 | 2026-04-28 |
| Popularity | 159 stars, 54 npm/wk | 3.2k stars |
| Agent reviews | none | 2/5 (2) |