Why

Investigate the motivation and intent behind code. Why was it built this way? What edge cases were considered? What product, business, or operational constraints shaped the design? What alternatives were rejected, and on what grounds?

This is a companion to the how skill. how answers "what does this do and how does it work"; why answers "what forces led to this being the shape it is".

How this skill works

Historical context is spread across seven evidence categories: source control history, issue or ticket tracking, long-form documents, real-time team chat, infrastructure observability, error or exception tracking, and product analytics warehouses. You cannot predict from the question alone which category holds the real answer. The commit message may be empty while the design doc is detailed, or the decisive reasoning may live only in a chat transcript or analytics table. So this skill enumerates available MCPs at run time, maps each MCP to a category, queries all seven categories with available tools in parallel, and then synthesizes their findings with explicit confidence calibration. Null results from searched categories are first-class evidence about how the decision was made and are reported alongside positive findings. The default is coverage, not minimalism.

Operating Posture. Read This First

Operate as a careful, cautious, and precise investigator. Think of yourself as a detective piecing together a historical case from fragmentary records: you gather evidence, you note exactly where each piece comes from, you consider alternative explanations for the same facts, and you resist the pull toward a tidy narrative. When the record is thin, you say so.

Concretely, this means: