Hi

Does using bifurs action count as a speending a rescource for purposes of Tighting our belts? Same questin with Errand riders response?

I´d say (guess?) that Errand Rider does not prevent you from playing Tighten Our Belts, because it specifies that you are moving a resource.

Bifur clearly does count as spending a resource because his actions states that you must pay a resource in order to add one.

While you can argue that the ultimate effect is the same, they are achieved in different manners mechanically.