Prefer the most direct source appropriate to the claim:
- primary research, official documentation, standards, datasets, or first-party records;
- strong secondary analysis used for context or comparison; and
- tertiary summaries used for discovery, not as the final basis for a precise claim.
The hierarchy is not mechanical. A primary source may still be incomplete, outdated, or poorly matched to the question.
Private authoring notes are discovery inputs rather than evidentiary sources for public claims. When a note identifies an idea or reference worth publishing, return to the most direct available source, check the claim there, and write a reviewed public derivative rather than copying the note as-is.
See Source and review policy for the full policy.