confidence-engine/docs/experiment-60b55.md

Experiment 60B.55 — Closure-normalization consolidation

Date: 2026-08-14 Branch: feature/closure-selection-reconciliation-v0.41

Purpose

Consolidate and commit the already-proven closure-normalization fix after focused regression verification.

Implementation state consolidated

The committed fix consists of four bounded changes only:

1. reverse resolution reconciliation

   • updatedNodes.newStatus = "resolved"
   • -> resolvedUnknownNodeIds automatically includes that existing unknown node

2. stale same-turn selectedQuestion clearing

   • if selectedQuestion.nodeId is resolved by the same proposal
   • -> selectedQuestion = null before strict validation

3. prompt clarification

   • selectedQuestion must remain unresolved after applying the proposal
   • if all consequential unknowns resolve, selectedQuestion must be null

4. repaired deterministic 60B.47 negative-closure regression structure

Focused verification result

Command run:

npx vitest run \
  tests/graph/apply-proposal.test.js \
  tests/graph/prompt-builder.test.js \
  -t "60B.49|60B.52|60B.54|60B.43|60B.11|replaces downstream pricing|selectedQuestion|resolution"

Result:

• PASS — 38 passed | 151 skipped

Verified behaviours

Exact negative closure regression

The exact 60B.47-shaped deterministic regression now passes through applyValidatedProposal(...) with:

• customer factor resolved
• decision resolved
• resolvedUnknownNodeIds / resulting resolvedNodeIds containing both IDs
• activeUnknownNodeId = null
• selectedQuestion = null

Reconciliation invariants

Verified preserved:

• forward reconciliation
• already-consistent proposal unchanged
• no duplicate resolved IDs
• non-unknown nodes are not auto-added
• non-resolved statuses are not auto-added

Fallback preservation

Verified preserved:

• stale same-turn resolved selectedQuestion clears cleanly
• another genuine unresolved candidate still becomes the fallback target

Existing behavioural regressions preserved

Verified preserved:

• 60B.43 terminal post-mutation closure regression
• 60B.11 preferred-target behaviour
• pricing prerequisite-first regression
• prompt-builder selectedQuestion rule regression

What is now guaranteed

The deterministic engine now normalizes same-turn closure structure coherently before strict validation:

• resolved existing unknowns are represented in both status and resolvedUnknownNodeIds
• a same-turn resolved selectedQuestion cannot survive as stale structure
• strict validator semantics remain intact

What remains unproven

The exact live negative-outcome closure still needs one bounded rerun after this deterministic fix to confirm the same end state through the live model-driven path.