From a logged decision to durable rationale Diagram

One independent decision

Use the existing record when it already owns the concern.
Choose a type by the decision, rather than by the implementation file.

A self-contained argument

Write neutral Context, the active-voice Decision and its Consequences.
Frontmatter, filename and heading agree on the typed ID.

Keep it current

Review the choice and its rationale before treating the record as authority.
Index foundations before dependants; edit live records in place.