diff --git a/types/index.d.ts b/types/index.d.ts
index 4a4c4ba..463db17 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -35,8 +35,8 @@ declare namespace fastifyOauth2 {
     scope?: string[];
     credentials: Credentials;
     callbackUri: string;
-    callbackUriParams?: Object;
-    tokenRequestParams?: Object;
+    callbackUriParams?: Record<string, string>;
+    tokenRequestParams?: Record<string, string>;
     generateStateFunction?: FastifyGenerateStateFunction;
     checkStateFunction?: FastifyCheckStateFunction;
     startRedirectPath?: string;
@@ -149,11 +149,11 @@ declare namespace fastifyOauth2 {
 
         getNewAccessTokenUsingRefreshToken(
             refreshToken: Token,
-            params: Object,
+            params: Record<string, string>,
             callback: (err: any, token: OAuth2Token) => void,
         ): void;
 
-        getNewAccessTokenUsingRefreshToken(refreshToken: Token, params: Object): Promise<OAuth2Token>;
+        getNewAccessTokenUsingRefreshToken(refreshToken: Token, params: Record<string, string>): Promise<OAuth2Token>;
 
         generateAuthorizationUri(
             request: FastifyRequest,
@@ -169,21 +169,22 @@ declare namespace fastifyOauth2 {
         revokeToken(
             revokeToken: Token,
             tokenType: TToken,
-            httpOptions: Object | undefined,
+            httpOptions: Record<string, string> | undefined,
             callback: (err: any) => void
         ): void;
 
-        revokeToken(revokeToken: Token, tokenType: TToken, httpOptions: Object | undefined): Promise<void>;
+        revokeToken(revokeToken: Token, tokenType: TToken, httpOptions: Record<string, string> | undefined): Promise<void>
 
         revokeAllToken(
             revokeToken: Token,
-            httpOptions: Object | undefined,
+            httpOptions: Record<string, string> | undefined,
             callback: (err: any) => void
         ): void;
         
         revokeAllToken(revokeToken: Token, httpOptions: Object | undefined): Promise<void>;
 
-        userinfo(tokenSetOrToken: Token | string): Promise<Object>;
+        revokeAllToken(revokeToken: Token, httpOptions: Record<string, string> | undefined): Promise<void>
+    }
 
         userinfo(tokenSetOrToken: Token | string, userInfoExtraOptions: UserInfoExtraOptions | undefined): Promise<Object>;
 
diff --git a/types/index.test-d.ts b/types/index.test-d.ts
index e73745d..9aa2634 100644
--- a/types/index.test-d.ts
+++ b/types/index.test-d.ts
@@ -1,5 +1,5 @@
-import fastify from 'fastify';
-import {expectAssignable, expectError, expectNotAssignable, expectType} from 'tsd';
+import fastify, { FastifyInstance, FastifyRequest } from 'fastify';
+import {expectAssignable, expectError, expectType, expectNotAssignable} from 'tsd';
 import fastifyOauth2, {
     FastifyOAuth2Options,
     Credentials,
@@ -9,7 +9,6 @@ import fastifyOauth2, {
     UserInfoExtraOptions
 } from '..';
 import type { ModuleOptions } from 'simple-oauth2';
-import { FastifyInstance } from 'fastify';
 
 /**
  * Preparing some data for testing.
@@ -45,13 +44,15 @@ const OAuth2Options: FastifyOAuth2Options = {
     credentials: credentials,
     callbackUri: 'http://localhost/testOauth/callback',
     callbackUriParams: {},
-    generateStateFunction: function () {
+    generateStateFunction: function (request) {
       expectType<FastifyInstance>(this)
-      return 'test'
+      expectAssignable<FastifyRequest>(request);
+      return 'test';
     },
-    checkStateFunction: function () {
+    checkStateFunction: function (request, callback) {
       expectType<FastifyInstance>(this)
-      return true
+      expectAssignable<FastifyRequest>(request);
+      expectType<(err: any) => void>(callback);
     },
     startRedirectPath: '/login/testOauth',
     cookie: {
@@ -152,7 +153,7 @@ expectType<string[]>(scope);
 expectType<string[]>(tags);
 expectType<Credentials>(credentials);
 
-// Ensure duplicayed simple-oauth2 are compatible with simple-oauth2
+// Ensure duplicated simple-oauth2 are compatible with simple-oauth2
 expectAssignable<ModuleOptions<string>>(credentials);
 expectAssignable<ModuleOptions["auth"]>(auth);
 // Ensure published types of simple-oauth2 are accepted