Lessons — Search, Apply & Create

Lessons capture hard-won knowledge that prevents the same mistake from being made twice.

Per Reinertsen (The Principles of Product Development Flow), product development generates two distinct types of knowledge:

Process lessons (category: process): Knowledge about how to build — methods, tools, techniques, workflow. Example: "Mocking the DB in integration tests hides migration bugs."
Domain lessons (category: domain): Knowledge about what to build — the product, users, requirements, the problem space. Example: "Users need batch export, not single-file export."

Both types are equally valuable but serve different purposes. Process lessons improve how agents work. Domain lessons improve what agents build.

Catalog Structure

The lessons catalog lives at .compass/meta/lessons-catalog.yaml. It provides O(1) tag lookup instead of O(n) grep across all lesson files.

Lessons capture hard-won knowledge that prevents the same mistake from being made twice.

Per Reinertsen (The Principles of Product Development Flow), product development generates two distinct types of knowledge:

Process lessons (category: process): Knowledge about how to build — methods, tools, techniques, workflow. Example: "Mocking the DB in integration tests hides migration bugs."
Domain lessons (category: domain): Knowledge about what to build — the product, users, requirements, the problem space. Example: "Users need batch export, not single-file export."

Both types are equally valuable but serve different purposes. Process lessons improve how agents work. Domain lessons improve what agents build.

The lessons catalog lives at .compass/meta/lessons-catalog.yaml. It provides O(1) tag lookup instead of O(n) grep across all lesson files.