core/docs/analysis/comprehension-capability-ledger-2026-06-07.md

Comprehension capability ledger (N1)

As of: merged main @ 51b4a6e3 (R2 batch #624–#627 merged).

This ledger answers, for the merged baseline, exactly six questions — so the contemplation loop (N2–N6) never mistakes a faithful refusal for a missing capability:

What can CORE currently read?      -> §2, §4 (admitted families)
What can it solve?                 -> §4 (R2 solver) + §2 (R1 answer lane)
What does it refuse?               -> §3, §5 (remaining refusals)
Which refusals are correct boundaries?   -> §6 (must_remain_refused = yes)
Which refusals are growth surfaces?      -> §6 (proposal_allowed = yes)
Which organ owns each refusal?           -> §6 (owner)

The load-bearing distinction, repeated on purpose: correct refusal ≠ missing capability. A refusal that is the wrong=0 boundary working (a pronoun with no referent, a system with no integer solution) must stay refused. The learning loop may only propose against refusals that are genuine coverage gaps (§6). N4 encodes this per-family; N5 emits proposals only for proposal_allowed = true rows.

1. Merged baseline (verified on merged main)

• R1 setup 7 / 0 / 3 · R1 answers 7 / 0 / 3 · 15-case 15 / 0 / 0
• R2 reader 10 setup_correct / 0 setup_wrong / 3 refused · R2 gold 13 / 13 valid (7 solved + 3 solver-refused + 3 reader-refused)
• Serving unchanged (every PR's pinned-lane SHA check green)

Two independent, off-serving setup compilers now exist with typed success/refusal states — enough substrate for a disciplined "think again" loop without LLM-style handwaving.

2. R1 admitted families (generate/quantitative_comprehension.py)

Relational single-quantity arithmetic, graded by evals/setup_oracle + the independent evals/relational_metric oracle. 7 families: fact; more/fewer-than; times-as-many; half-as-many (exact divide); multi-step chain; aggregate-then-divide partition; additive aggregate-query; narrow inverse (base of a more/fewer-than). All compute exact integer answers. Detail: r1-inventory-ledger-2026-06-07.md.

3. R1 remaining refusals (all correct wrong=0 boundaries)

r1-08 pronoun (no grounded referent) · r1-09 ungrounded base (no grounded fact) · r1-10 distractor (compound clause the X has N unit template cannot parse). Each must stay refused; admitting any would breach wrong=0. None is a coverage gap.

4. R2 admitted families (generate/constraint_comprehension/)

Two-category finite-integer count/weight systems: read → exact Cramer solve → answer-choice verify (with contradiction flagging). 6 families: buses/seats, animals/legs, tickets/price, coins/value, boxes/capacity, vehicles/wheels. Detail: r2-inventory-ledger-2026-06-07.md, ADR-0217.

5. R2 remaining refusals

• Reader (gold-backed): too_many_categories (>2), missing_total_count, missing_weighted_total. Defensive (constructed-test): coefficient_unit_mismatch, coefficient_conflict, category_pair_not_found, query_target_not_a_category.
• Solver: indistinguishable_weights, non_integer_solution, negative_solution, verification_failed.
• Answer-choice: no_matching_option, ambiguous_options, unknown_provided_label, unparseable_option, no_options; plus the contradiction verdict (not a refusal).

6. Cross-organ refusal taxonomy draft (formalized by N4)

First-pass mapping of the full refusal surface to the failure-family vocabulary, with must_remain_refused (correct boundary) and proposal_allowed (growth surface) and owner. N4 turns this into the executable registry; N5 emits proposals only for proposal_allowed.

Family	Evidenced by	owner	must_remain_refused	proposal_allowed
ambiguous_referent	R1 pronoun unreadable_quantity_clause	r1	yes	no (needs entity-resolution design)
ungrounded_base	R1 unit_unbound, no_single_quantity_query	r1	yes	no
unsupported_distractor_clause	R1 r1-10 unreadable_quantity_clause	r1	yes	no (until same-unit target isolation)
unit_incompatible	R1 unit_mismatch, R2 coefficient_unit_mismatch	cross	yes	no
unsupported_system_size	R2 too_many_categories	r2	yes	no (until ≥3-var solver, R3)
missing_category_pair	(reserved — category_pair_not_found is too broad; see note)	r2	no	yes (reserved)
missing_attribute_coefficient	(reserved — no emitter yet)	r2	no	yes
missing_total_count	R2 missing_total_count	r2	no	yes (propose count-constraint fixture)
missing_weighted_total	R2 missing_weighted_total	r2	no	yes (propose weighted-total fixture)
indistinguishable_weights	R2 solver	r2	yes	no
non_integer_solution	R2 solver	r2	yes	no
negative_solution	R2 solver	r2	yes	no
answer_key_contradiction	R2 answer-choice contradiction verdict	r2	n/a	no — action: report contradiction
input_shape	R1 non_digit_quantity/non_identifier_name/no_quantity_template/unprojectable; R2 query_target_not_a_category/category_pair_not_found	cross	yes	no

N6 correction (boundary-first + precise growth). category_pair_not_found fires on any non-R2 text (0 or 1 categories), so it is not a safe growth trigger — it maps to input_shape ("R2 does not recognize this"), and missing_category_pair is reserved until the reader distinguishes a partial one-category R2 problem from non-R2 prose. Only the precise R2 gaps (missing_total_count, missing_weighted_total — reachable only after two categories + matching coefficients are read) remain reachable growth surfaces. The contemplation pass (N6) classifies boundary-first and treats input_shape as non-blocking, so a problem one organ recognizes as a substantive boundary never proposes against the other organ's broad refusal.

Reserved (forward-declared, no current emitter): missing_category_pair, missing_attribute_coefficient, unsupported_rate_duration, unsupported_temporal_state — named so the registry is complete, but not reachable until the reader/R3 supplies a precise signal.

7. Next contemplation batch (N2–N6)

N2  core/comprehension_attempt/   typed ComprehensionAttempt (organ + outcome + refusal_reason + family + signature + evidence)
N3  setup router                  try R1 then R2; exactly-one setup_correct -> use; else typed refusal
N4  failure-family registry       executable form of §6 (must_remain_refused / proposal_allowed / owner)
N5  proposal-only emitter         teaching/proposals/comprehension_failures/<content_hash>.json — never mounted
N6  generate/contemplation/ v0    single bounded pass chain: route -> classify -> terminal -> maybe emit

8. Non-claims / boundaries

• This is not a new capability batch. R1/R2 capability is unchanged; N2–N6 add a growth organ, not new math.
• setup_wrong / answer_wrong stay 0; serving stays unchanged.
• No self-modification. The loop's terminal action is at most a proposal-only artifact. It cannot ratify, mount, alter a reader, or modify tests except by a human-reviewed PR. The alignment is failure → classification → proposal → review → ratification, never failure → self-patch. (CLAUDE.md teaching-safety; ADR-0055/0056/0057.)
• R2 generalization to real GSM8K prose remains R3, not claimed here.