Good names are the cheapest documentation a config file can have. The Env Variable Naming Reference & Glossary checks a name against the conventions that make env files portable and self-explanatory, then tells you what it means.
Type a variable (or a KEY=value line) and the tool reports style verdicts, splits the name into domain/modifier/property, guesses its category, flags secret-looking keys, and looks it up in a glossary of common variables. With empty input it becomes a full reference table of the most frequent keys across major stacks.