12. A system for selecting a package model, comprising: a package model database configured to: store a data structure of a plurality of package models and one or more attribute relationships, wherein each package model has a plurality of package model attributes comprising at least a size and a style, wherein each attribute relationship includes an indication that one or more supplemental attributes are required if a constraint is satisfied; and a semantic reasoner configured to: receive a user input that is descriptive of a desired package capability, wherein the desired package capability comprises requirements for the package model, analyze the user input to determine one or more desired attributes, access the data structure to automatically determine whether a desired attribute satisfies a constraint for an attribute relationship, and present the one or more supplemental attributes required by the attribute relationship.
12. A system for selecting a package model, comprising: a package model database configured to: store a data structure of a plurality of package models and one or more attribute relationships, wherein each package model has a plurality of package model attributes comprising at least a size and a style, wherein each attribute relationship includes an indication that one or more supplemental attributes are required if a constraint is satisfied; and a semantic reasoner configured to: receive a user input that is descriptive of a desired package capability, wherein the desired package capability comprises requirements for the package model, analyze the user input to determine one or more desired attributes, access the data structure to automatically determine whether a desired attribute satisfies a constraint for an attribute relationship, and present the one or more supplemental attributes required by the attribute relationship. 13. The system of claim 12 wherein the semantic reasoner is further configured to: receive the one or more supplemental attributes; automatically select one or more package models by accessing the data structure, wherein, for each selected package model, each desired attribute and each supplemental attribute satisfies the corresponding package model attribute; and present the one or more selected package models.