# Document Transcription System Overview (Version 4)

This directory is the single source of truth for current V4 behavior and architecture.

## Canonical Reading Order

1. [System Architecture](architecture_v4.md) for runtime topology, boundaries, and lifecycle ownership.
2. [System Requirements](requirements_v4.md) for verifiable current-state requirements.
3. [Data Model](schema_v4.md) for entities, constraints, and evidence persistence rules.
4. [Error Handling Policy](error_handling_v4.md) for category, translation, and retry behavior.

## Cross-Version Invariants

- [Historical Document Transcription Design Intent](../invariant/intent.md)
- [Transcription Methodology](../invariant/transcription_methodology.md)
- [Error Handling](../invariant/error_handling.md)
- [Digital Evidence and AI Processing Provenance](../invariant/ai_evidence_and_provenance.md)
- [UI Style Guide](../invariant/ui_style_guide.md)

## Baseline Statement

The current V4 baseline includes behavior delivered through V4.7 architectural cleanup.
Use only this `docs/ver4/*` tree for active design and implementation decisions.