.... In order to properly use the jscodeshift API, one has to understand the basic building blocks of recast (and ASTs) as well. An AST node is a plain JavaScript object with a specific set of fields, in accordance with the Mozilla Parser API. The primary way to identify nodes is via their type. It's OK to not know the structure of every AST node type. The (esprima) AST explorer is an online tool to inspect the AST for a given piece of JS code.