Open Specification

ACEC

Agent Commerce Execution Contract

ACEC is a narrow execution standard that defines how machine-initiated transactions are quoted, executed, and receipted. It specifies the minimal contract between agents and merchants—nothing more.

What ACEC covers

Quoting
Structured requests for pricing and availability
Execution
Atomic transaction operations with validation
Receipts
Cryptographic proofs of completed transactions

What ACEC does not cover

User interfaces
How agents or humans interact with commerce
Product catalogs
How merchants organize or present inventory
Marketplaces
Aggregation, discovery, or comparison experiences
AI prompts
Natural language processing or intent extraction

Design principles

  • 01
    Minimal surface area

    Only specify what is strictly necessary for execution.

  • 02
    Transport agnostic

    Works over HTTP, message queues, or direct integration.

  • 03
    Verifiable by default

    Every operation produces cryptographic proof.

  • 04
    Forward compatible

    Designed for extension without breaking existing implementations.

Read the specification

The canonical home of the ACEC specification.

agentcec.org