The document provides an overview of the services offered by the Java Development Tools (JDT) Core and UI for extending JDT and becoming a JDT tool smith. It summarizes the three main pillars of JDT - the Java model, search engine, and abstract syntax tree (AST). The Java model is a lightweight model for views. The search engine allows quick access to declarations and references through indexing. The AST provides a precise, fully resolved compiler parse tree for code manipulation.