core/docs/decisions/adr-012-l10-grounding.md

ADR-012-L10-Grounding — L10 finite grounding pack and adversarial wrong=0 fixtures

Status: Proposed
Date: 2026-06-05
Scope: Additive pack + additive eval fixtures only
Branch: feat/l10-grounding-pack-evals-adr

Context

CORE is migrating toward an L10 runtime thread: a stateless, hyper-efficient, content-addressed execution layer. The transition must preserve CORE's existing doctrine: deterministic replay, refusal before invention, finite proof surfaces, and geometric reasoning over compiled structure rather than probabilistic guessing.

The immediate failure class is not arithmetic. It is relational grounding. A system that treats vacuous universals, unbound existentials, or contradictory premise sets as license to fabricate relational links will pass superficial natural-language tests while violating CORE's wrong=0 doctrine.

This ADR proposes an additive seed pack and an additive adversarial fixture set for the L10 transition. No existing runtime, parser, solver, loader, or pack is modified.

Decision

Adopt language_packs/data/l10_grounding_v1/ as the first L10-oriented grounding pack.

The pack contains finite-domain relational primitives only:

• finite entity grounding
• witness binding
• range restriction
• guarded universal
• grounded existential
• vacuous-truth refusal guard
• contradiction barrier
• no-explosion barrier
• finite-domain closure
• undecidable-refusal mapping

Every lemma is namespaced with l10_ to avoid global lemma collisions. The pack manifest uses oov_policy = "fail_closed" and declares l10_stateless = true.

Adopt evals/deductive_logic/fixtures/l10_adversarial.jsonl as independent-gold adversarial cases for wrong=0 behavior. Gold labels are symbolic, not model-inferred. The fixture set explicitly covers vacuous truth, range restriction, contradictory premises, unbound existential witnesses, finite closure, and no-explosion refusal.

Relationship to CORE-AI geometric reasoning doctrine

CORE's geometric doctrine requires that meaning be carried through stable structure and admissible transformations, not guessed associations. L10 grounding preserves that doctrine by refusing to project an ungrounded relational edge into the substrate.

For a future L10 compiler, these primitives should lower into content-addressed operators whose admissibility depends on explicit finite witnesses and guards. A universal over an empty guard may be logically vacuous, but it must not create an entity-specific rotor edge. A contradictory premise set may identify a real boundary, but it must not explode into arbitrary entailments.

Stateless execution alignment

The pack and fixtures are L10-compatible because:

1. All rows are self-contained JSON records.
2. No row depends on mutable global state, online lookup, model inference, or hidden cache.
3. All fixture gold labels are derivable from finite premise lists.
4. The fixture format includes explicit finite_domain, premises, query, gold, and symbolic_resolution fields.
5. OOV behavior is fail-closed by manifest declaration.

Wrong=0 doctrine

The expected wrong value for every fixture is 0. Any uncertain or inconsistent proposition must resolve to refuse, not a guessed truth value.

This is especially load-bearing for:

• vacuous universals with no explicit witness
• existential claims without a bound witness
• range-restricted rules whose guard is not satisfied
• premise sets that derive incompatible heads
• contradictory entity facts

Checksums

• language_packs/data/l10_grounding_v1/lexicon.jsonl: 829efd10d7f5fa74f1189ec6d621f2a12bc5e7a022fd7a3de436655fc8fe5603
• evals/deductive_logic/fixtures/l10_adversarial.jsonl: beda988f019b5431a3ab6e817b463a165bde719c7597f3b6a7f572107e1db123

Consequences

Positive:

• Establishes a clean L10 seed surface without refactoring existing code.
• Gives the wrong=0 gate concrete adversarial cases before the L10 runtime exists.
• Prevents hallucinated relation links from being treated as legitimate inference.

Negative / deferred:

• No runtime loader is added in this PR.
• No test harness is added in this PR.
• The filename requested here is adr-012-l10-grounding.md; this is a working L10 proposal and should be reconciled with the existing ADR registry before final numbering or merge.

Verification plan

To be completed in the Claude lane or local CI after review:

1. Confirm all lemma values in l10_grounding_v1/lexicon.jsonl are globally unique across every pack.
2. Confirm the lexicon checksum matches the manifest checksum.
3. Confirm the adversarial fixture checksum matches this ADR.
4. Add a future symbolic runner that derives each fixture gold label without model inference.
5. Require wrong=0: no false positives, no hallucinated links, no ex-falso entailment.

Non-goals

• No serving-code mutation.
• No eval-runner mutation.
• No parser mutation.
• No loader mutation.
• No new dependency.
• No empirical claim that the fixtures pass before they are run.