Normalization rules

This section defines how Tropos and other producers transform source tool structures into Forma. These rules exist to ensure that equivalent source inputs yield equivalent Forma output.

Rule 1 · Stable identifiers

Node identifiers must be stable across re-exports when the source node identity is stable. Source ids may be mapped directly or normalized into a deterministic id function.

Rule 2 · Layout precedence

When a container can be represented as directional flow, producers must emit flex or stack rather than absolute. Absolute is a fallback, not a default.

Rule 3 · Token resolution

When a style value matches a declared token exactly, producers must emit the token reference. Literal values are only allowed when no stable token mapping exists.

Normalization area	Required behavior	Fallback
Parent-child structure	Preserve logical hierarchy and child order	Emit issue if source structure is malformed
Component instances	Normalize reusable elements to component nodes with variant metadata when available	Emit as container with flag instance_unresolved
Layout	Prefer flex or stack for auto-layout-like patterns	Emit absolute with layout_fallback
Spacing	Normalize padding and gap into token references when available	Emit literal number or string
Semantic role	Emit the most specific justified role	Emit no role plus ambiguity issue
Text	Emit text content on text nodes	Emit issue if text content is missing

Role inference guidance

Use explicit source metadata first.
Then use normalized naming and component set semantics.
Then use layout, style, and child-pattern heuristics.
When uncertainty remains, omit role and emit an ambiguity issue.

Confidence scoring

Confidence reflects certainty in inferred fields, not overall document quality.

Explicit source semantics: high confidence
Pattern-based inference: medium confidence
Heuristic fallback: low confidence plus flags