Point
The current format is the only contract
HEAD defines one format-1 behavior without compatibility code, parallel schemas, or fallback processing.
- Posture
- asserted
- Lifecycle
- active
The root declares "format": 1. The released specification, schemas, validator, fixtures, normalized output, Meta-Atlas, and release gates implement that contract only. Immutable specification and processor revisions identify the exact pre-1.0 contract. Earlier experiments remain in the separate dated archive and do not create aliases, migration behavior, parallel schemas, or fallback processing in the active repository.
One contract reduces ambiguity for authors and independent implementers. A future compatibility surface would become a current maintenance promise and therefore requires present evidence, explicit scope, and synchronized tests rather than an assumption that historical behavior must remain executable.
Syntax and discoveryRejecting old paths and aliases keeps discovery and parsing on a single current grammar.
Conformance evidenceOne HEAD contract gives implementations one observable behavior to reproduce rather than a compatibility matrix.