1. A method executed at least in part in a computing device to generate automatic command shell command code based on a schema, the method comprising: receiving the schema that includes one or more of: element declarations, attribute declarations, simple type definitions and complex type definitions; reading the schema to create a model for classes that include an interface and a structure, wherein the classes validate constraints in the schema; optimizing the model to translate the schema to an application programming interface (API); and inserting a plug-in to the optimized model to generate a command for a command shell based on the optimized model by; disabling generation of a default code for the command, using the plug-in; and generating a plug-in code for the command, using the plug-in, wherein the command manipulates data that is structured based on the classes according to a class definition in a data store associated with the schema defined by the optimized model at runtime.