diff --git a/src/evaluate.ts b/src/evaluate.ts
index b9e9608..f901f9f 100644
--- a/src/evaluate.ts
+++ b/src/evaluate.ts
@@ -2,10 +2,20 @@ import {type Opt} from "./deep.ts";
 import {base64Encode} from "./base64.ts";
 import {utfEncode} from "./text.ts";
 
+/**
+* Auxiliary type for default export.
+*/
 export interface DefExp<T extends unknown>{
     default: T;
 }
 
+/**
+* Evaluate ESM JavaScript code in module scope.
+* @example
+* ```ts
+* const {default: data} = await evaluateESM<DefExp<string>>("export default 'hello!';");
+* ```
+*/
 export async function evaluateESM<T extends Opt<T>>(code:string):Promise<T>{
     return await import(`data:text/javascript;base64,${base64Encode(utfEncode(code))}`);
 }
\ No newline at end of file