Glossary
Source age
How old the document behind a citation is, shown so you can judge currency.
A correct citation of an obsolete page is still a trap. Source age puts the document's age next to the sentence so you can see that the procedure you were handed might predate the tool you use now. Age does not decide which source wins. It stops you from treating every citation as current.
Cairn shows source age with the citation and with confidence. It also flags conflicts when sources disagree. The situation this is built for is a Slack thread and a Notion page that drifted, which is Ask Slack and Notion, and read the source age.