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What is A202?

Status: Informative in full. This page answers the questions a reader or a software agent asks first, in plain terms. Every rule it mentions is normative in the specification document it links to, and where this page and a specification document disagree, the document is the definition.

What is A202?

A202, the Verifiable Agreement Protocol for Agent-Led Commerce, is an open, carrier-neutral specification of commercial authority, negotiation state, and verifiable conformance for transactions between independent organisations, including transactions conducted on their behalf by software agents. It defines typed objects for delegated commercial authority, a state machine for the transaction and for each bilateral session inside it, rules for what may be disclosed to whom, and an executable conformance suite that turns each of those rules into a check an implementation either passes or fails.

In one sentence: A202 specifies how two organisations that have never transacted before — or their agents — reach commitments that either side can later prove, from the record alone.

What does the name mean?

The name is A202, spoken "A two-oh-two". The long form, A202, the Verifiable Agreement Protocol for Agent-Led Commerce, is a descriptor and not an expansion: the letters do not stand for it. The 202 is HTTP 202 Accepted, the status an accepted submission returns under A202-0017, because acceptance is the primitive the rest of the specification is built on.

What problem does it solve?

When software agents transact for organisations, the questions that matter are not how messages travel but what they commit anyone to. A202 gives both sides a shared, checkable answer to five questions no message transport answers: who authorised this act (commercial mandate), what state the transaction is in and what changed it (transaction state machine), what was agreed and what is owed (obligation), what each side was allowed to learn (canonical commercial model), and what can be proven a year later, by whom, from what (evidence verification).

What is A202 not?

  • Not a payment protocol. A202 stops at the settlement handoff: an authorised instruction to a payment rail. It moves no money.
  • Not a transport. A202 is carrier-neutral: it defines what objects mean, not how they travel. Objects may be carried by A2A, exposed over MCP, or referenced by another protocol without changing what they mean.
  • Not an identity scheme. Parties bring their own keys; A202 defines what a signature over canonical bytes commits the signer to.
  • Not an agent framework. A202 constrains what agents may commit their principals to, whatever software the agents are built with.

The full statement of scope and non-goals is the charter.

How does A202 relate to AP2, ACP, A2A, and MCP?

AP2 (the Agent Payments Protocol) and ACP (the Agentic Commerce Protocol) answer payment-shaped questions: proving a purchaser authorised a payment, and executing checkout. A202 specifies the layer those protocols assume: how the agreement being paid for was formed, under whose authority, with what negotiation history and disclosure record, and how any of it is verified. A2A and MCP are carriers A202 objects travel over — see A202 with A2A and MCP and the comparison page for the field-by-field picture.

Who is behind A202, and under what terms?

A202 was created by A. A. Musse and is sponsored by Plural Worlds, under a published governance document that states what the sponsor does and does not control. The whole repository — specification text, schemas, fixtures, and reference implementation — is licensed under the Apache License, Version 2.0, which carries an express patent grant from each contributor. A202™ is a trademark of Plural Worlds; permitted use is stated in TRADEMARK.md.

What is its status?

Pre-release. The contents are v0.1 working documents under the release policy in RELEASES.md; no release has been tagged. The conformance suite currently holds 148 executable fixtures, and every normative change lands under a numbered, public proposal.

Where does an agent start?