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+# Session 2026-06-19 — Semantic substrate affordances, contract readiness, and the foundation audit pivot
+
+**Status:** recorded for continuation. **Headline:** After #829–#831 made `ProblemFrame` operational and measurable, the session clarified that the next foundation problem is not another local parser or premature organ migration. The core design target is a **semantic-substrate affordance loop**: words and chunks probe the substrate, surface nearby constructional meanings and relation families, bind roles to exact evidence spans, and only then allow `ContractAssessment` / organs to determine or refuse.
+
+`Docs-only record. No runtime, serving, eval report, pack, corpus, policy, identity, or sealed artifact changes are made by this session note.`
+
+---
+
+## TL;DR
+
+1. **#831 changed the truth metric.** The project moved from surface/schema recognition to measurable contract readiness: typed mentions, bindings, bound relations, bound question targets, and pure `ContractAssessment` diagnostics. #831's merged evidence recorded `candidate contracts = 42/423`, `runnable contracts = 1/1`, serving still `train 30/20/0`, `holdout 5/495/0`, with `wrong_ids=[]`.
+2. **GPT-5.5 Thinking XHIGH rejected premature `percent_partition` migration.** The decision memo concluded that readiness was still obligation-loose: broadening extraction or migrating `percent_partition` would preserve or amplify false readiness. The recommended next implementation is proportional-change contract closure: bind `decrease_to_fraction`, delta targets, and organ-specific blockers while correcting the false runnable holdout.
+3. **The constitutional program was refined, not adopted monolithically.** The correct split is three layers: a small constitutional kernel (`ADR-0223` later), a mutable critical-program roadmap, and versioned evidence profiles. The canonical spine must use semantic roles, not force `PropositionGraph` into a universal reasoning carrier; ADR-0144 distinguishes articulation `PropositionGraph`, epistemic `EpistemicGraph`, and math problem state.
+4. **The operator's design correction became the key doctrine.** Dead giveaways are not isolated trigger words. They are **constructional affordances**. A chunk such as `buys 3 more apples` should probe the substrate and surface acquisition / transaction / positive possession-delta affordances, then bind actor, quantity, item, prior state, optional cost, and target.
+5. **CGA semantic nearness remains essential but not sufficient.** Substrate proximity should propose candidate nodes and relation families (`buy ≈ purchase ≈ acquire ≈ gain`), while exact span bindings and contracts determine whether anything can be asserted. The governing rule: **closeness proposes; bindings ground; contracts determine.**
+6. **A foundation audit is required before broad substrate work.** The current risk is accumulating local recognizers and false contract candidates instead of building the intended semantic substrate. A new ADR is required to mandate a deep, repository-wide substrate-alignment audit before agents make broad foundational changes.
+
+---
+
+## Context entering the session
+
+The active stack after the latest merged work:
+
+| PR | Meaning |
+|---|---|
+| #829 | Kernel Substrate Tranche 1: scalar equivalence, unit dimensions, ambiguity hazards, process-frame schemas, `ProblemFrame` skeleton, morphology foundations. |
+| #830 | `ProblemFrame` operationalization and legacy-deprecation guardrails. |
+| #831 | Span-grounded mentions/bindings/relations, bound question targets, `ContractAssessment`, adequacy reporting, and contract-gap morphology recommendations. |
+
+#831's evidence established that readiness must be measured by **runnable contracts**, not by recognized schema presence. The merged PR body recorded:
+
+```text
+Train 50:
+  entity mention present: 50
+  quantity binding present: 46
+  bound process relation present: 16
+  bound question target present: 42
+  candidate contracts: 42
+  runnable contracts: 1
+
+Holdout 500:
+  entity mention present: 494
+  quantity binding present: 452
+  bound process relation present: 124
+  bound question target present: 402
+  candidate contracts: 423
+  runnable contracts: 1
+```
+
+This means CORE now has a measurable bridge from text into typed readiness, but the bridge is thin. It proves the method, not broad serving readiness.
+
+---
+
+## The XHIGH decision memo
+
+The next-decision prompt asked GPT-5.5 Thinking XHIGH to choose the highest-leverage PR after #829–#831. The decision memo recommended:
+
+```text
+feat(kernel): close proportional-decrease contracts and make readiness obligation-sound
+branch: codex/problemframe-proportional-change-closure
+```
+
+The reasons:
+
+- Current readiness blockers are not yet sufficiently precise.
+- `percent_partition` readiness is too loose: candidates can arise from broad `partition`/`consumption` recognition rather than full topology and target-direction proof.
+- The existing false runnable holdout is an inverse-reconstruction case outside the forward `percent_partition` contract.
+- `fraction_decrease` has mature confusers and a clear train case (`0005`) that can prove a second genuine ProblemFrame-runnable contract without serving migration.
+
+Expected diagnostic movement:
+
+```text
+Train runnable contracts: 1 → 2
+  - 0005: fraction_decrease
+  - 0046: percent_partition
+
+Holdout runnable contracts: 1 → 0
+  - remove the false positive; this is a truthfulness improvement, not a regression.
+```
+
+Hard boundary: no serving integration, no derivation-organ migration, no `math_candidate_graph.py` change, no `report.json`, no sealed mutation, and no raw-text fallback behind a `ProblemFrame` call.
+
+---
+
+## The constitutional-program correction
+
+A broader AGI-capable constitutional plan was discussed. The useful direction was kept, but two important corrections were made:
+
+### 1. Split constitution, roadmap, and evidence profiles
+
+The correct structure is:
+
+```text
+1. Small constitutional ADR kernel.
+2. Mutable critical-program roadmap.
+3. Versioned evidence profiles with frozen benchmarks/thresholds.
+```
+
+This keeps benchmark churn and implementation sequencing from rewriting the constitution. A future claim such as `agi-capable-v1` should be reproducible against a frozen evidence profile, not embedded forever in the constitutional core.
+
+### 2. Do not make `PropositionGraph` universal
+
+The first constitutional spine over-named `PropositionGraph`. ADR-0144 already separates:
+
+- `generate.graph_planner.PropositionGraph` — articulation planner.
+- `recognition.carrier.EpistemicGraph` — epistemic/provenance carrier.
+- `MathProblemGraph` / math state — mathematical reasoning state.
+
+The corrected constitutional spine uses semantic roles:
+
+```text
+observation
+→ grounded evidence
+→ domain frame
+→ admissible domain model
+→ verified derivation/proof
+→ epistemic standing
+→ articulation plan or authorized action
+```
+
+For the current math path, the realization is narrower:
+
+```text
+text
+→ KernelFacts
+→ ProblemFrame
+→ ContractAssessment
+→ contract-backed derivation organ
+→ independently verified resolution
+→ existing admission and articulation path
+```
+
+This preserves ADR-0207's anti-universal-IR posture: use typed adapters between domain structures; do not introduce another universal reader/graph by accident.
+
+---
+
+## The operator's substrate doctrine correction
+
+The operator challenged a simplified explanation that treated `buys` as a generic cue for addition. The corrected doctrine is:
+
+```text
+Dead giveaways are constructional affordances, not isolated trigger words.
+```
+
+A word such as `buys` does not merely mean `add`. It probes a semantic neighborhood:
+
+```text
+buy / bought / purchase / acquire / get / gain / receive
+→ acquisition
+→ transaction
+→ possession change
+→ positive object delta
+→ optional money/cost delta
+```
+
+But the meaningful unit is often the chunk:
+
+```text
+buys 3 more apples
+```
+
+That chunk should surface:
+
+```text
+surface chunk: "buys 3 more apples"
+semantic neighborhood: buy, purchase, acquire, gain possession, transaction
+construction: actor buys quantity more entity
+roles:
+  buyer
+  acquired_quantity = 3
+  acquired_entity = apples
+  same_entity_continuation = true
+  object_delta = positive
+optional roles:
+  price
+  seller
+  money_delta
+operator candidates:
+  add_to_inventory
+  compute_cost
+  compute_remaining_money, if money target is present
+hazards:
+  entity mismatch
+  target mismatch
+  negation
+  comparison rather than acquisition
+```
+
+The same principle applies to proportional change:
+
+```text
+decrease to 3/4 of 84 degrees
+```
+
+should surface:
+
+```text
+semantic affordance: proportional state change
+construction: state decreases to fraction of base
+roles:
+  base quantity = 84 degrees
+  target scale = 3/4
+  relation = decrease_to_fraction
+question target:
+  delta decrease, if asked "how much did it decrease by"
+blocked cases:
+  final-value question
+  affine-more-than fraction
+  multiple fractions
+  ambiguous base
+```
+
+---
+
+## Working model: substrate-mediated cognition loop
+
+The intended loop is:
+
+```text
+chunk enters the field
+→ nearby semantic / constructional affordances resonate
+→ candidate nodes and relation families surface
+→ roles bind to exact evidence spans
+→ organ-specific contracts assess obligations
+→ determination, refusal, articulation, or action follows
+```
+
+Or shorter:
+
+```text
+chunk
+→ semantic neighborhood
+→ constructional affordance
+→ role obligations
+→ bound relation candidate
+→ contract assessment
+```
+
+This is the bridge between the CGA substrate and the typed problem-solving stack.
+
+The CGA inner product / substrate should provide **semantic gravity**: related meanings and constructions become easy to retrieve. But closeness does not license truth. Truth promotion requires grounded bindings and contracts.
+
+Canonical rule:
+
+```text
+closeness proposes;
+bindings ground;
+contracts determine.
+```
+
+---
+
+## Foundation risk identified
+
+The operator's warning was accepted: if the project builds a pile of local recognizers, it will become harder each sprint. Every later capability will fight earlier shortcuts.
+
+The dangerous path:
+
+```text
+surface keyword
+→ local regex
+→ one-off organ behavior
+→ patch more confusers forever
+```
+
+The intended path:
+
+```text
+surface chunk
+→ substrate affordance retrieval
+→ constructional role binding
+→ ProblemFrame relation
+→ ContractAssessment obligations
+→ verified derivation or refusal
+```
+
+Therefore, before broad foundation changes, CORE needs a deep audit of how the current codebase aligns or misaligns with the intended substrate-mediated cognition loop.
+
+---
+
+## New ADR required
+
+This session produced the requirement for a new ADR:
+
+```text
+ADR-0223: Semantic Substrate Affordance Audit and Foundation Alignment
+```
+
+The ADR must require a deep-dive research pass over small and large details that may be blocking the intended design, including but not limited to:
+
+- lexical vs constructional affordances;
+- local regex recognizers vs substrate-backed constructional retrieval;
+- ProblemFrame binding quality;
+- false runnable contracts;
+- relation topology and question-target direction;
+- graph/carrier boundaries (`ProblemFrame`, `EpistemicGraph`, `PropositionGraph`, math state);
+- legacy parser bypasses;
+- substrate pack coverage;
+- morphology/planner recommendation evidence;
+- proof/admission boundaries;
+- exact recall / CGA-neighborhood usage;
+- places where the code's foundation makes later correctness harder.
+
+The ADR should authorize research and recommendations, not immediate destructive edits. Any proposed removal, replacement, or consolidation must return as evidence-backed proposals and separate implementation PRs.
+
+---
+
+## Immediate plan of record
+
+1. Continue with the already-selected implementation PR:
+
+```text
+feat(kernel): close proportional-decrease contracts and make readiness obligation-sound
+branch: codex/problemframe-proportional-change-closure
+```
+
+2. Record this session and ADR as docs-only work.
+3. Keep `percent_partition` deferred until its topology, target direction, and heterogeneous positive evidence are sufficient for ProblemFrame-only migration.
+4. Use the new ADR to guide a high-skill research/audit effort, not to authorize unreviewed rewrites.
+
+---
+
+## Open / next
+
+- Run or commission the substrate-affordance audit required by ADR-0223.
+- Ensure the proportional-decrease PR interprets `decrease to <fraction> of <state>` as a constructional affordance, not as keyword matching.
+- Update future constitutional documents to use semantic roles rather than concrete universal graph classes.
+- Consider adding the doctrine below to architecture docs after ADR-0223 is ratified:
+
+```text
+Words and chunks are probes into the semantic substrate.
+They surface candidate affordances and relation families.
+Only grounded bindings and contracts can promote those affordances into determinations.
+```