In most cases, the tools must run on the same hardware platform as the test object itself. This, however, can have an influence on the run time behavior (like memory and processor usage) of the test object and influence the test results. This must be remembered when using such tools and evaluating test results.
Since such tools need to be connected to the particular test object's test interface, they vary greatly depending on the test level (component, integration, system test) in which they are applied.
When speaking of test tools in general, we often mean tools for automating test execution, i.e., tools for automating dynamic tests.
Source: Software Testing Foundations
Andreas Spillner, Tilo Linz: Software Testing Foundations, A Study Guide for the Certified Tester Exam, dpunkt.verlag.