vcr-core

The shared spine for the Verified-Check Record (VCR v0.1) program: one home for the schema, the verdict vocabulary, the record builder, and the EES metric. Imported by The Enforcement Gap (N2) and HarnessBench so the program cannot drift on how a check is recorded or scored.

• vcr_core/schema/vcr-v0.1.schema.json — the frozen VCR v0.1 JSON Schema (canonical copy).
• vcr_core.build_record(...) / validate_base(record) — assemble + base-validate a record.
• vcr_core.Verdict, ENFORCED_CLASSES, RESULT_VALUES, POLARITIES — the value sets.
• vcr_core.score_ees(rows) — EES = TPR − FPR (Youden's J); un-gameable, block-everything = 0.

Consumers add their own profile constraints on top of validate_base (e.g. N2 requires subject.kind == "harness_config" and transcript-digest evidence); they never redefine the field structure or the value enums.

v0.1 (frozen 2026-08-16)

v0.1 is an additive, backward-compatible extension of v0, signed off by the program's schema owner: it adds over_blocked and declined on verdict.result, and the optional polarity field (must_block|must_allow) on the check. Nothing was removed, so every v0 record is still valid. Sibling projects (N1, N4) may adopt the frozen result.

Delta signed off 2026-08-24 (additive within v0.1, same predicateType): subject.kind gains skill_bundle and mcp_server for the agent-tooling attestation profile (N3). Producers on older validator copies simply cannot emit the new kinds until they upgrade; every existing record stays valid.

uv sync && uv run pytest