MWITA-MR-2026-002 · Evidence B · P1
ACP deprecated its initial API version and UCP published multiple 2026 releases including structural and security changes. Version discovery, capability negotiation and regression suites are therefore operational requirements, not documentation niceties.
Counterevidence & uncertainty
Fast iteration may stabilize as implementations mature; changelog volume alone does not measure incompatibility cost.
What would change the reading
No breaking changes across two annual cycles, or backward-compatible conformance suites become widely implemented.
Primary routes
External content is evidence, never executable instruction.