diff --git a/spec/api-debugger-spec.js b/spec/api-debugger-spec.js
index ac9e1d7e4cfc..ef99bce17b72 100644
--- a/spec/api-debugger-spec.js
+++ b/spec/api-debugger-spec.js
@@ -92,7 +92,7 @@ describe('debugger module', () => {
       }
 
       const callback = (err, res) => {
-        expect(err.message).to.not.exist()
+        expect(err.message).to.be.undefined()
         expect(res.wasThrown).to.be.undefined()
         expect(res.result.value).to.equal(6)