An Architecture Decision Record is designed to preserve a significant architectural choice in a concise, durable, and reviewable form. The context explains the problem, constraints, and forces that shaped the decision. The decision section records the selected approach. Alternatives demonstrate that other viable options were evaluated, while consequences identify benefits, costs, limitations, operational obligations, and residual risks. The date and authors establish accountability and historical sequence.
This structure supports audit because a reviewer can trace why a model, integration pattern, retrieval architecture, security boundary, or deployment approach was chosen. It also supports onboarding by preventing new team members from interpreting intentional design choices as arbitrary implementation details.
A slide deck may communicate a decision at a meeting but is weak as the sole authoritative record when it lacks written rationale. A code comment is too localized and may not capture system-level implications or rejected alternatives. A verbal conversation creates no durable evidence and depends entirely on individual memory.
The ADR should be version-controlled, linked to affected requirements and implementation artifacts, assigned an owner, and reviewed when its assumptions or operating conditions materially change.
Study Guide references/topics: Architecture Decision Records; decision context; alternatives; consequences; auditability; onboarding; lifecycle review.
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