Proviso

A proviso may be a ginger, lily-livered construction, but at least it does something: it takes a stated general principle and weasels out of it.

“The promisor herewith agrees to pay, unconditionally and in full, all amounts due, provided that on no account shall the promisor be liable for: … [here follows a catalogue of exceptions great and small the sum total of which will equal, or perhaps even exceed, the value of the commitment so generously given].”