tempus-mutatur

Apply a model-era delta to this repo's instruction layer — establish from evidence which model family the files were written for, then list what current guidance changes, as edits to your files rather than as research. Use for "these instructions were written for an older model", "what changed for the 5-family", "are we still writing for Sonnet 3.5", "is any of this advice out of date", "we have a model ID hardcoded…