A lookup path is an identifier with an optional path suffix that resolves to a [path value](@docroot@/language/types.md#type-path) if the identifier matches a search path entry in [`builtins.nixPath`](@docroot@/language/builtins.md#builtins-nixPath).
The algorithm for lookup path resolution is described in the documentation on [`builtins.findFile`](@docroot@/language/builtins.md#builtins-findFile).