Alternatives
A2A alternatives: 9 documented options compared (November 2026)
The main documented alternatives to A2A are Agent Network Protocol, Agentic Commerce Protocol, AGNTCY, Google Connected Apps Platform, Model Context Protocol, PACT, Personal Agent Protocol, Universal Commerce Protocol, and WebMCP.
Last verified 2026-11-03
Earlier records in this comparison were checked from 2026-10-20 through 2026-11-03.
Comparison
A cell reads not documented when the directory has no sourced value. The first row is this listing. The other rows are alphabetical by name.
| Listing | Status | Open source | Tags | Custody model | Rail or protocol | Per-payment cap | Payee or protocol allowlist | License |
|---|---|---|---|---|---|---|---|---|
| A2AThis listing | Live | Yes | discovery, agent-cards, json-rpc | not documented | not documented | not documented | not documented | Apache-2.0. |
| Agent Network Protocol | Beta | Yes | identity, discovery, did | not documented | not documented | not documented | not documented | Apache-2.0. The README points at the repository LICENSE file. |
| Agentic Commerce Protocol | Live | Yes | commerce, checkout, delegation | Card vault token | cards | Yes | Partial | Apache-2.0. |
| AGNTCY | Live | Yes | discovery, identity, messaging | not documented | not documented | not documented | not documented | Apache-2.0. |
| Google Connected Apps Platform | Beta | No | mcp, tools | not documented | not documented | not documented | not documented | not documented |
| Model Context Protocol | Live | Yes | tools, resources, prompts | not documented | not documented | not documented | not documented | New code and specifications are Apache-2.0. Documentation other than specifications is CC-BY-4.0. Some earlier contributions remain under MIT until the author agrees to relicense. |
| PACT | Beta | Yes | consent, identity, a2a | not documented | not documented | not documented | not documented | Apache-2.0. |
| Personal Agent Protocol | Designed | Yes | consent, oauth, discovery | not documented | not documented | not documented | not documented | Apache-2.0. |
| Universal Commerce Protocol | Live | Yes | commerce, checkout, discovery | not documented | not documented | not documented | not documented | Apache-2.0. |
| WebMCP | Beta | Yes | browser, tools, mcp | not documented | not documented | not documented | not documented | The spec says the report is published by the Web Machine Learning Community Group under the W3C Community Contributor License Agreement (CLA). |
How to choose
A2A is compared with the other listings in Protocols.
Tags on A2A are discovery, agent-cards, json-rpc.
Other tags differ across the table.
Status is Live for A2A, Agentic Commerce Protocol, AGNTCY, Model Context Protocol, and Universal Commerce Protocol. Status is Beta for Agent Network Protocol, Google Connected Apps Platform, PACT, and WebMCP. Status is Designed for Personal Agent Protocol.
Open source is yes for A2A, Agent Network Protocol, Agentic Commerce Protocol, AGNTCY, Model Context Protocol, PACT, Personal Agent Protocol, Universal Commerce Protocol, and WebMCP. Open source is no for Google Connected Apps Platform.
Custody model for A2A is not documented. Other values are Card vault token for Agentic Commerce Protocol.
The table has 10 rows. The first row is A2A. The other 9 rows are alphabetical by name. This page does not score listings.
Listings
- A2AThis listing
- Agent Network ProtocolAlternative
- Agentic Commerce ProtocolAlternative
- AGNTCYAlternative
- Google Connected Apps PlatformAlternative
- Model Context ProtocolAlternative
- PACTAlternative
- Personal Agent ProtocolAlternative
- Universal Commerce ProtocolAlternative
- WebMCPAlternative
Comparisons
Questions
- What are the documented alternatives to A2A?
- The main documented alternatives to A2A are Agent Network Protocol, Agentic Commerce Protocol, AGNTCY, Google Connected Apps Platform, Model Context Protocol, PACT, Personal Agent Protocol, Universal Commerce Protocol, and WebMCP.
- How were these alternatives chosen?
- They are the other listings in Protocols. A page is built only when that set has at least 3 other listings. Peers are alphabetical by name. The page does not score listings and does not read sponsor records.
- What does the phrase not documented mean?
- The phrase not documented means the directory has no sourced value for that field on that listing. The page does not fill a blank with a guess.
- Which fields are compared?
- The table columns are Status, Open source, Tags, Custody model, Rail or protocol, Per-payment cap, Payee or protocol allowlist, and License.
- Is there a comparison page or a gap note?
- Yes. A2A vs AGNTCY, A2A vs Agent Network Protocol, and A2A vs Model Context Protocol pair A2A with one of these alternatives. A gap note for A2A is linked on this page.
- When was this page updated?
- The newest date among the records used here is 2026-11-03.