Goal Recognition (GR) is a research problem that studies ways to infer the goal of an intelligent agent based on its observed behavior and knowledge of the environment. A common assumption of GR is that the underlying environment is stationary. However, in many real-world scenarios, it is necessary to recognize agents’ goals over extended periods. Therefore, it is reasonable to assume that the environment will change throughout a series of goal recognition tasks. This paper introduces the problem of continuous GR over a changing environment. The solution to this problem is a GR system capable of recognizing agents’ goals over an extended period where the environment in which the agents operate changes. To support the evaluation of candidate solutions to this new GR problem, in this paper, we present the Goal Recognition Amidst Changing Environments (GRACE) tool for generating instances of the new problem. Specifically, the tool can be configured to generate GR problems that account for different environmental changes and drifts. GRACE can generate a series of modified environments over discrete time steps and the data induced by agents operating in the environment while completing different goals.