In this paper, we present two novel contributions to improve human-machine collaboration (HMT) research: 1) a Minecraft testbed to accelerate the testing and deployment of collaborative AI agents, and 2) a tool for replaying and analyzing behavior within HMT episodes to facilitate the development of shared mental models. The browser-based Minecraft testbed enables rapid testing of collaborative agents in a continuous spatial, real-time, and partially observable environment without the cumbersome setup typically associated with human-AI interaction user research. Furthermore, Minecraft's extensive user base and rich ecosystem of pre-built AI agents can rapidly facilitate the design of novel collaborative agents and research into understanding various human factors within HMT. The mental model alignment tool supports user-directed post-mortem analysis, including video displays of first-person perspectives of team members (i.e., humans and AI), and provides a chat interface leveraging GPT-4 to answer various queries about the AI's experience and model details.