diff --git a/types/cote/cote-tests.ts b/types/cote/cote-tests.ts
index 8fd52a73a4..1851654625 100644
--- a/types/cote/cote-tests.ts
+++ b/types/cote/cote-tests.ts
@@ -80,10 +80,10 @@ class Readme {
             payload: { val: number };
         }
 
-        randomResponder.on('randomRequest', (req: RandomRequest, callback: (answer: number) => void) => {
+        randomResponder.on('randomRequest', (req: RandomRequest, callback: (error: any, answer?: number) => void) => {
             const answer = Math.floor(Math.random() * 10);
             console.log('request', req.payload.val, 'answering with', answer);
-            callback(answer);
+            callback(null, answer);
         });
     }
 
diff --git a/types/cote/index.d.ts b/types/cote/index.d.ts
index f6c60c54a2..4c959af76b 100644
--- a/types/cote/index.d.ts
+++ b/types/cote/index.d.ts
@@ -1,6 +1,7 @@
-// Type definitions for cote 0.14
+// Type definitions for cote 0.17
 // Project: https://github.com/dashersw/cote#readme
 // Definitions by: makepost <https://github.com/makepost>
+//                 Labat Robin <https://github.com/roblabat>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
 import { EventEmitter2 } from "eventemitter2";
@@ -55,7 +56,7 @@ export class Requester extends Component {
      * @param event Request.
      * @param callback Function to execute after getting a result.
      */
-    send<T extends Event>(event: T, callback: (result: any) => void): void;
+    send<T extends Event>(event: T, callback: (error: any, result: any) => void): void;
 }
 
 /**
@@ -100,7 +101,7 @@ export class Responder extends Component {
     on<T extends Event>(
         type: string | string[],
         listener: (
-            ((event: T, callback: (result: any) => void) => void) |
+            ((event: T, callback: (error: any, result: any) => void) => void) |
             ((event: T) => Promise<any>)
         )
     ): this;