Six months after a design is built, the question people ask is never what was chosen; that is visible in the running system. The question is why, and whether the reason still holds. A decision record answers it in four short parts. Context is the forces in play at the time, including the numbers you had and the attribute you were trying to buy. Options are the alternatives you genuinely considered, each stated well enough that a reader can see it was a real candidate and not a straw one. Decision is the option chosen and, crucially, the deciding attribute, the one that broke the tie. Consequences are what the choice now costs, including the work it makes harder later. Each record covers exactly one decision, is dated, is short enough to read in two minutes, and is never edited after the fact. When a decision is later replaced, you write a new record that supersedes the old one and leave the old one standing, because the history of why is the whole value. A record with no rejected option in it is not a decision record; it is a description of the system that was going to be built anyway. You can now write a record for a decision you have made that lets a stranger reconstruct your reasoning without asking you.
An Architectural Decision Record (ADR) is a concise, structured artifact that documents an architecturally significant decision by capturing its context, the options considered, the rationale for the…