diff --git a/packages/babel-parser/ast/spec.md b/packages/babel-parser/ast/spec.md
index e8b5120b13..7160972803 100644
--- a/packages/babel-parser/ast/spec.md
+++ b/packages/babel-parser/ast/spec.md
@@ -1149,6 +1149,7 @@ A specifier in an import or export declaration.
 ```js
 interface ImportDeclaration <: ModuleDeclaration {
   type: "ImportDeclaration";
+  importKind: null | "type" | "typeof" | "value";
   specifiers: [ ImportSpecifier | ImportDefaultSpecifier | ImportNamespaceSpecifier ];
   source: Literal;
 }
@@ -1156,6 +1157,8 @@ interface ImportDeclaration <: ModuleDeclaration {
 
 An import declaration, e.g., `import foo from "mod";`.
 
+> importKind is only set when `flow` plugin enabled in babel-parser
+
 ### ImportSpecifier
 
 ```js