diff --git a/packages/env/src/tokenizers/node.ts b/packages/env/src/tokenizers/node.ts
index 3f7b3207c3d14a46bf61139ce0e8386d45a52597..6f0db4ca1d237195cdfaa8fc403fdc95d006d986 100644
--- a/packages/env/src/tokenizers/node.ts
+++ b/packages/env/src/tokenizers/node.ts
@@ -25,7 +25,7 @@ class TokenizerSingleton {
     };
   }
 
-  tokenizer(encoding?: Tokenizers) {
+  tokenizer(encoding?: Tokenizers): Tokenizer {
     if (encoding && encoding !== Tokenizers.CL100K_BASE) {
       throw new Error(`Tokenizer encoding ${encoding} not yet supported`);
     }
@@ -34,5 +34,5 @@ class TokenizerSingleton {
   }
 }
 
-export const tokenizers = new TokenizerSingleton();
+export const tokenizers: TokenizerSingleton = new TokenizerSingleton();
 export { Tokenizers, type Tokenizer };