Collaboration drives innovation across industries, yet assessing its effectiveness remains challenging and, for technology-mediated environments, unaddressed. While existing research focuses on human-to-human, human-computer, and data collaboration, few studies evaluate human collaboration facilitated by computers. Building on Marek et al.’s Collaboration Assessment Toolkit (CAT) [1], we developed the UX-CAT, an evaluation framework tailored for technology-facilitated collaboration. In a case study at LiveRamp, a data collaboration company, we validated the UX-CAT using responses from 134 users of our products. Confirmatory factor analysis showed that the six factors of the conceptual evaluation model—Purpose, Process, Members, Resources, Communication, and Data—had strong internal consistency. Additionally, intercorrelations between the factors and their alignment with perceived collaboration success confirmed the model’s validity. We hope this work can provide the Human Computer Interaction community with an empirically tested tool for measuring the effectiveness of technology-based collaboration and offer insights into how design can foster successful collaborative outcomes.