Two types of dynamically hooked procedural chains.
"Chain - simple": linear chain between origins of two hook objects. Specify approximate link size, it will calculate the exact number and size of links to fit into the interval.
"Chain - complex": chain with realistic sagging and a limited ability to "slide" along hooks (only works if both hooks have mesh along direct line of sight between their origins.) Reduces to basic chain if you uncheck "Gravity" and "Slide along mesh".
Configure either via "Modifiers" -> "GeometryNodes".