Extracting Spec / Design Ladders

Purpose

Turn read-only source into two separated layers with non-overlapping responsibilities: a faithful reproduction spec (enough to rebuild observable behavior) and an abstract design doc (intent and experience, deliberately stripped of reproduction detail).

When to Use

• Recovering intent and reproducible behavior from an existing program.
• Producing documentation that must let someone REBUILD behavior (spec) and, separately, understand DESIGN intent (design doc) without the two contaminating each other.

When Not to Use

• Pure summary or README work where reproduction fidelity is not required.
• When a maintained spec already exists and only needs editing.