The model code will be annotated with the following set of metadata: name of model, link to model description, contact information, date of model creation, distribution terms, model specifications, model implementation of those specifications, disease, region of analysis, types of intervention strategies, computer resource requirements, user's manual (link), validation measures (link to supporting manuscript), and compile and/or run scripts. The information about model specification and how those specifications were implemented is particularly important for explaining model differences. For example, if an implementation strategy calls for a reduction of 50% in model contacts, it is plausible to implement the strategy by halving the number of people contacted or alternatively maintaining the same number of persons in the contact network while halving the number of contacts with each person. The model results for each of the implementations could vary significantly.