Building Semantic Schema

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A schema is a formal, machine-readable contract that declares what exists, what it means, and what must be true—without saying how to build it

A schema is not

A schema is not any of the following:

• Geometry
• Code
• Instructions
• Algorithms
• Drawings
• A script
• A model in FreeCAD

All of the above are derived artifacts — they are produced *from* a schema by compilers, generators, or humans, but they are not the schema itself.