Introduction

"How does Cogitave do X?" used to have no single answer. The reuse-first principle - discover before you generate - was already stated as a hard rule, but an agent facing "stand up a REST service" still had to reconstruct the golden path by hand: which standard governs it, which template to start from, which anti-pattern to avoid. Reconstructing that path every time, inconsistently, is exactly the divergence the reuse-first rule exists to kill, one layer up.

The patterns catalog is the artifact that closes that gap. For every recurring build task it names the one Cogitave-sanctioned way to solve it and points at the authority that owns the rules. It is the paved road, made queryable in one hop instead of re-derived across dozens of standards.

This module builds on the first module in this path, Reuse-first engineering, which taught why discover-before-generate is the rule. This module teaches how to act on it: reading a catalog entry, using the machine-readable index behind it, and running the loop that takes you from "I need to do X" to "I am extending a named artifact." The decision to add both artifacts is recorded in ADR-0022.

What you will get from this module

By the end you will be able to explain what the catalog is for, read any entry's five fixed sections without confusing the pointer for the policy, find the pattern for a task and follow its two links - the governing standard and the reusable artifact - and run the four-step discover-before-you-build loop, including the honest path for when nothing fits.