diff --git a/README.md b/README.md
index 7cde648..350f611 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 # json-rpc-ts
 
 [![deno.land/x](https://shield.deno.dev/x/json_rpc_ts)](https://deno.land/x/json_rpc_ts)
+[![ci](https://github.com/yieldray/json-rpc-ts/actions/workflows/ci.yml/badge.svg)](https://github.com/yieldray/json-rpc-ts/actions/workflows/ci.yml)
 
 A strictly typed json-rpc(2.0) implementation, zero dependency, minimal abstraction, with simple api
 
diff --git a/src/client.ts b/src/client.ts
index f6827d3..df167ea 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -18,7 +18,7 @@ type JSONRPCAnyRequest =
  * The client cannot parse the server response
  */
 export class JSONRPCClientParseError extends Error {
-    name = 'JSONRPCClientParseError'
+    override name = 'JSONRPCClientParseError'
     request: JSONRPCAnyRequest
     constructor(message: string, request: JSONRPCAnyRequest) {
         super(message)
diff --git a/src/dto/errors.ts b/src/dto/errors.ts
index 2536c0c..15b81bf 100644
--- a/src/dto/errors.ts
+++ b/src/dto/errors.ts
@@ -24,7 +24,7 @@ export class JSONRPCError extends Error implements JSONRPCErrorInterface {
      * The error codes from and including -32768 to -32000 are reserved for pre-defined errors. Any code within this range, but not defined explicitly below is reserved for future use. The error codes are nearly the same as those suggested for XML-RPC at the following url: http://xmlrpc-epi.sourceforge.net/specs/rfc.fault_codes.php
      */
     public code: number
-    public message: string
+    public override message: string
     public data?: JSONRPCValue
 
     public constructor(object: JSONRPCErrorInterface) {
diff --git a/src/dto/request.ts b/src/dto/request.ts
index 1affe44..712ba59 100644
--- a/src/dto/request.ts
+++ b/src/dto/request.ts
@@ -49,7 +49,7 @@ export class JSONRPCRequest extends JSONRPCNotification {
         this.id = object.id
     }
 
-    public toString() {
+    public override toString() {
         return JSON.stringify({
             jsonrpc: this.jsonrpc,
             method: this.method,