How ACK protocol versions are managed and identified.
The Agent Commerce Kit (ACK) specifications as a whole use string-based version identifiers following the format YYYY-MM-DD
. This date indicates when the last set of backwards-incompatible changes were introduced to the core protocols (ACK-ID or ACK-Pay).
The protocol version identifier will typically not change when updates are made that maintain backwards compatibility (e.g., adding optional parameters, clarifying existing behavior). This allows for incremental improvements while preserving interoperability with implementations based on the same or earlier compatible versions within a dated release.
Specific documentation versions or implementations might be marked as:
The current stable protocol version is 2025-05-04.
(Note: Specific implementation libraries or SDKs built upon ACK may follow their own versioning schemes, like Semantic Versioning, but should clearly state which ACK protocol version YYYY-MM-DD
they are compatible with.)