This paper presents a case study to describe the features and the phases of the two agent methodologies. The Gaia methodology for agent oriented analysis and design, Tropos is a detailed agent oriented software engineering methodology to explore each methodology's ability to present solutions for small problems. Also we provide an attempt to discover whether the methodology is in fact understandable and usable. In addition we were collecting and taking notes of the advantages and weaknesses of these methodologies during the study analysis for each methodology and the relationships among their models. The Guardian Angle: Patient-Centered Health Information System (GA: PCHIS) is the personal system to help track, manage, and interpret the subject's health history, and give advice to both patient and provider is used as the case study throughout the paper.