`core demo anti-regression` (+ `--json`) is a self-contained walkthrough of
the three independent gates that every reviewed-corpus extension must pass.
Designed for showcasing CORE's epistemic discipline to reviewers / industry
observers — no LLM provider has a published equivalent.
Scenes:
- S1. Eligibility predicate refuses an undetermined-polarity candidate
before any replay is invoked. ProposalError raised; no log row.
- S2. Replay-equivalence gate auto-rejects a regressing candidate with
the named regressed metrics in the operator note. Uses the documented
`run_replay=` kwarg of `propose_from_candidate` to inject a controlled
regression of the same `ReplayEvidence` shape the real gate produces.
- S3. Real `teaching.replay.run_replay_equivalence` runs the cognition
public lane. A replay-equivalent candidate reaches 'pending' — operator
`--accept` is still required to write.
Each scene asserts the active corpus is byte-identical pre/post.
- evals/anti_regression/run_demo.py — `run_demo(emit_json=False)` returns
a structured `DemoReport`; verbose human output by default, JSON on flag.
- core/cli.py — `core demo anti-regression` target wired alongside
audit-tour / pack-measurements / long-context-comparison.
- tests/test_anti_regression_demo.py — 5 tests pin each scene's
load-bearing claim + the corpus-byte-identical invariant.
Lane state: anti-regression-demo 5 new — green. Demo runs in ~10s end-to-end.
