# Opus Review

**Model:** claude-opus-4
**Generated:** 2026-03-02T12:30:00Z

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## Summary Assessment

This is a well-structured, detail-rich plan. The Transform3D decomposition section is admirably precise, the test strategy is grounded in real fixture data, and the two-pass architecture is sound. That said, there are several significant issues that will cause implementation trouble if not addressed beforehand.

## Critical Issues

### 1. Multiline Property Values Are Dramatically Under-Scoped
The plan acknowledges multiline values as a risk but the parser architecture describes a line-by-line state machine with no actual design for multiline accumulation. main.tscn contains 52 `_surfaces = [{...}]` blocks spanning many lines with nested structures. Needs: bracket/parenthesis depth tracking, dictionary value parser entry, nested value parsing.

### 2. Missing Fixture File
`furniture_slot_placeholder.tscn` is referenced but does not exist. Actual files: worker.tscn, fdm_printer.tscn, filament_spool_item_new.tscn, main.tscn. Tests depending on it need retargeting.

### 3. Negative Scale / Determinant Check Missing
Scale extraction always produces positive values via sqrt(). Needs determinant sign check for mirrored objects. Godot's basis.cpp handles this via determinant sign.

## Significant Issues

4. State machine should allow arbitrary section ordering for robustness
5. Property delimiter is ` = ` (space-equals-space), not bare `=`
6. Groups attribute parsing needs explicit array-in-header handling
7. `instance=ExtResource("id")` in header needs value parser invocation
8. `unique_id` should be explicit decision (int vs str)

## Moderate Issues

9. No 2D transform decomposition (Transform2D) — should be explicitly deferred
10. Query methods should handle missing resource IDs gracefully
11. find_node path semantics for root node undefined
12. No blank line/comment handling specified
13. Old `resources` field removal not mentioned
14. Performance target needs packed array optimization as first-class concern

## Minor Issues

15. Scalar keywords (true/false/null) must be exact matches, not prefix
16. File encoding should be UTF-8 explicit
17. Transform3D decomposition tests should be standalone
18. parent field is str not reference — document tradeoff
19. Warning mechanism undefined (logging vs warnings.warn vs list)
20. Test count: 2+2+3+2+5+3+3+2 = 22, not 23

## Recommended Actions Before Implementation

1. Design multiline value accumulation algorithm
2. Fix or create furniture_slot_placeholder.tscn fixture
3. Add determinant sign check to Transform3D decomposition
4. Specify header attribute array parsing for groups and instance
5. Define warning/logging mechanism
6. Specify ` = ` as property delimiter
