A streams manager monitors data tuples processed by a streaming application represented by an operator graph. The streams manager includes a tuple breakpoint mechanism that allows defining a tuple breakpoint that fires based on resource usage by the data tuple. When the tuple breakpoint fires, one or more operators in the operator graph are halted according to specified halt criteria. Information corresponding to the breakpoint that fired is then displayed. The tuple breakpoint mechanism thus provides a way to debug a streaming application based on resource usage by data tuples.