The ODD (Overview, Design concepts, and Details) protocol was introduced in 2006 to standardize the description of individual-based and agent-based models (ABMs). Its primary goal is to make model descriptions more understandable and complete, reducing the risk of irreproducibility. A review of existing ODD applications revealed areas needing improvement and clarification, prompting an updated version of the protocol. The updated ODD aims to clarify aspects of the original version and enhance the rigor of model formulations, making theoretical foundations more visible. While initially designed for ABMs, ODD can also help document large, complex models, addressing general objections against such models. The review found that 75% of ODD-based model descriptions were either fully or mostly correct, with some elements being unclear or misinterpreted. The 'Design concepts' element was often underutilized, and 'Input' was frequently misinterpreted. The updated ODD clarifies these elements and adds two new design concepts: 'Basic principles' and 'Learning'. The protocol now includes seven elements: Purpose, Entities, State Variables, and Scales; Process Overview and Scheduling; Design Concepts; Initialization; Input Data; and Submodels. Each element is described with questions and explanations to ensure clarity and completeness. The updated ODD protocol is designed to be a comprehensive checklist for describing ABMs, ensuring that important design decisions are made consciously. It addresses the need for rigorous model formulation, facilitates reviews and comparisons of ABMs, and promotes holistic approaches to modeling and theory. While ODD has limitations, such as its focus on specific model versions, it is recommended for use in model descriptions. The protocol has gained increasing acceptance, with citations of the original ODD paper rising significantly, indicating its growing role as a standard format for ABM descriptions.The ODD (Overview, Design concepts, and Details) protocol was introduced in 2006 to standardize the description of individual-based and agent-based models (ABMs). Its primary goal is to make model descriptions more understandable and complete, reducing the risk of irreproducibility. A review of existing ODD applications revealed areas needing improvement and clarification, prompting an updated version of the protocol. The updated ODD aims to clarify aspects of the original version and enhance the rigor of model formulations, making theoretical foundations more visible. While initially designed for ABMs, ODD can also help document large, complex models, addressing general objections against such models. The review found that 75% of ODD-based model descriptions were either fully or mostly correct, with some elements being unclear or misinterpreted. The 'Design concepts' element was often underutilized, and 'Input' was frequently misinterpreted. The updated ODD clarifies these elements and adds two new design concepts: 'Basic principles' and 'Learning'. The protocol now includes seven elements: Purpose, Entities, State Variables, and Scales; Process Overview and Scheduling; Design Concepts; Initialization; Input Data; and Submodels. Each element is described with questions and explanations to ensure clarity and completeness. The updated ODD protocol is designed to be a comprehensive checklist for describing ABMs, ensuring that important design decisions are made consciously. It addresses the need for rigorous model formulation, facilitates reviews and comparisons of ABMs, and promotes holistic approaches to modeling and theory. While ODD has limitations, such as its focus on specific model versions, it is recommended for use in model descriptions. The protocol has gained increasing acceptance, with citations of the original ODD paper rising significantly, indicating its growing role as a standard format for ABM descriptions.