Derive codebase context

An agent working in a repository of a few thousand files cannot hold its shape. The reflex is to build a code knowledge graph. The measurements say do something cheaper and more durable: derive three artifacts from the tree itself, commit them, and gate each one in CI so it cannot rot.

This skill is the order to build them in, how to tell whether a repository already has them, and the one discipline that decides whether any of it works.

What the evidence says

Read this before proposing a graph, because the graph is the thing people keep proposing.