Representation Surfaces

ARTI is best understood as a family of composable representation surfaces rather than one monolithic architecture.

Surface	Carries	Key APIs	Status
Literal text	Glyph appearance, controls, coordinates	TextTensorRenderer, render_text_bitmap	Alpha
Runtime vocabulary	Call-time item tensors and local slots	LiteralInput, OutputLexiconContext, LiteralOutputHead	Alpha
Latent state	Hidden tensors, masks, coordinates, visibility	Layer, ARTILayer	Stable Candidate core
Recall path	Candidate traces and selective residual updates	RecallRefiner, ARTILatentRecallField, layered Recall	Core plus experimental extensions
Workspace	Survival, compaction, learned pulses	Half, Fold, Pulse	Stable Candidate core
Source integrity	Superposed source bases and recoverability diagnostics	SourceIntegrityCarrier, source losses/reports	Experimental
Participant context	Viewer-relative coordinates and visibility	build_participant_context, membrane routing	Experimental
Visual field	Patch fragments, positions, scans, pulses	VisualField, VisualScan	Public, evolving surface
Fit toolchain	Scan, plan, insert, train, validate, export	arti.fit, ARTIProject	Tooling surface; verify per release

A compositional path

physical or literal input
  → explicit tensor carrier
  → mask / coordinate / visibility context
  → ARTI latent layer or attached Recall branch
  → Half survival
  → Fold or Pulse workspace
  → task-owned decoder or dynamic literal head

Not every application needs every stage. The important property is that each boundary remains an ordinary tensor contract and can be inspected or replaced independently.

Stable core versus research surface

ARTI 1.7.0 freezes the documented core layer, attachment, serialization, mask, coordinate, visibility, output, and diagnostic contracts. APIs explicitly marked alpha, experimental, or legacy are public for research and integration, but are not frozen at the same level. UnFold is in the supported core; FusionPulse and Web inspection remain Alpha.