diff --git a/src/Configuration/SdkConfiguration.php b/src/Configuration/SdkConfiguration.php
index 6c065d26..f460755b 100644
--- a/src/Configuration/SdkConfiguration.php
+++ b/src/Configuration/SdkConfiguration.php
@@ -102,7 +102,7 @@ public function __construct(
         private array $scope = ['openid', 'profile', 'email'],
         private string $responseMode = 'query',
         private string $responseType = 'code',
-        private string $tokenAlgorithm = 'RS256',
+        private string $tokenAlgorithm = Token::ALGO_RS256,
         private ?string $tokenJwksUri = null,
         private ?int $tokenMaxAge = null,
         private int $tokenLeeway = 60,
@@ -134,11 +134,10 @@ public function __construct(
         private ?ListenerProviderInterface $eventListenerProvider = null
     ) {
         if (null !== $configuration && [] !== $configuration) {
-            $configuration = $this->filterArrayMixed($configuration, true) ?? [];
-            $this->applyConfigurationState($configuration);
+            $this->applyConfiguration($configuration);
         }
 
-        $this->validateNamedParameters();
+        $this->validateProperties();
         $this->setupStateCookies();
         $this->setupStateFactories();
 
@@ -190,6 +189,10 @@ public function pushAudience(array|string $audiences): ?array
 
     public function setCookieDomain(?string $cookieDomain): self
     {
+        if (null !== $cookieDomain && '' === trim($cookieDomain)) {
+            $cookieDomain = null;
+        }
+
         $this->cookieDomain = $cookieDomain;
         return $this;
     }
@@ -207,6 +210,10 @@ public function hasCookieDomain(): bool
 
     public function setCookieExpires(int $cookieExpires = 0): self
     {
+        if ($cookieExpires < 0) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('cookieExpires');
+        }
+
         $this->cookieExpires = $cookieExpires;
         return $this;
     }
@@ -223,6 +230,10 @@ public function hasCookieExpires(): bool
 
     public function setCookiePath(string $cookiePath = '/'): self
     {
+        if ('' === trim($cookiePath)) {
+            $cookiePath = '/';
+        }
+
         $this->cookiePath = $cookiePath;
         return $this;
     }
@@ -239,6 +250,10 @@ public function hasCookiePath(): bool
 
     public function setCookieSameSite(?string $cookieSameSite): self
     {
+        if (null !== $cookieSameSite && '' === trim($cookieSameSite)) {
+            $cookieSameSite = null;
+        }
+
         $this->cookieSameSite = $cookieSameSite;
         return $this;
     }
@@ -256,6 +271,10 @@ public function hasCookieSameSite(): bool
 
     public function setCookieSecret(?string $cookieSecret): self
     {
+        if (null !== $cookieSecret && '' === trim($cookieSecret)) {
+            $cookieSecret = null;
+        }
+
         $this->cookieSecret = $cookieSecret;
         return $this;
     }
@@ -289,6 +308,10 @@ public function hasCookieSecure(): bool
 
     public function setClientId(?string $clientId = null): self
     {
+        if (null !== $clientId && '' === trim($clientId)) {
+            $clientId = null;
+        }
+
         $this->clientId = $clientId;
         return $this;
     }
@@ -306,6 +329,10 @@ public function hasClientId(): bool
 
     public function setClientSecret(?string $clientSecret = null): self
     {
+        if (null !== $clientSecret && '' === trim($clientSecret)) {
+            $clientSecret = null;
+        }
+
         $this->clientSecret = $clientSecret;
         return $this;
     }
@@ -407,6 +434,10 @@ public function hasHttpClient(): bool
 
     public function setHttpMaxRetries(int $httpMaxRetries = 3): self
     {
+        if ($httpMaxRetries < 0) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('httpMaxRetries');
+        }
+
         $this->httpMaxRetries = $httpMaxRetries;
         return $this;
     }
@@ -490,6 +521,10 @@ public function hasHttpTelemetry(): bool
 
     public function setManagementToken(?string $managementToken = null): self
     {
+        if (null !== $managementToken && '' === trim($managementToken)) {
+            $managementToken = null;
+        }
+
         $this->managementToken = $managementToken;
         return $this;
     }
@@ -660,6 +695,10 @@ public function hasRedirectUri(): bool
 
     public function setResponseMode(string $responseMode = 'query'): self
     {
+        if ('' === trim($responseMode)) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('responseMode');
+        }
+
         $this->responseMode = $responseMode;
         return $this;
     }
@@ -676,6 +715,10 @@ public function hasResponseMode(): bool
 
     public function setResponseType(string $responseType = 'code'): self
     {
+        if ('' === trim($responseType)) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('responseMode');
+        }
+
         $this->responseType = $responseType;
         return $this;
     }
@@ -746,6 +789,10 @@ public function hasSessionStorage(): bool
 
     public function setSessionStorageId(string $sessionStorageId = 'auth0_session'): self
     {
+        if ('' === trim($sessionStorageId)) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('sessionStorageId');
+        }
+
         $this->sessionStorageId = $sessionStorageId;
         return $this;
     }
@@ -819,6 +866,10 @@ public function hasTokenCache(): bool
 
     public function setTokenCacheTtl(int $tokenCacheTtl = 60): self
     {
+        if ($tokenCacheTtl < 0) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('tokenCacheTtl');
+        }
+
         $this->tokenCacheTtl = $tokenCacheTtl;
         return $this;
     }
@@ -835,6 +886,10 @@ public function hasTokenCacheTtl(): bool
 
     public function setTokenJwksUri(?string $tokenJwksUri = null): self
     {
+        if (null !== $tokenJwksUri && '' === trim($tokenJwksUri)) {
+            $tokenJwksUri = null;
+        }
+
         $this->tokenJwksUri = $tokenJwksUri;
         return $this;
     }
@@ -852,6 +907,10 @@ public function hasTokenJwksUri(): bool
 
     public function setTokenLeeway(int $tokenLeeway = 60): self
     {
+        if ($tokenLeeway < 0) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('tokenLeeway');
+        }
+
         $this->tokenLeeway = $tokenLeeway;
         return $this;
     }
@@ -903,6 +962,10 @@ public function hasTransientStorage(): bool
 
     public function setTransientStorageId(string $transientStorageId = 'auth0_transient'): self
     {
+        if ('' === trim($transientStorageId)) {
+            throw \Auth0\SDK\Exception\ConfigurationException::validationFailed('transientStorageId');
+        }
+
         $this->transientStorageId = $transientStorageId;
         return $this;
     }
@@ -1106,177 +1169,6 @@ private function setupStateStorage(): void
         }
     }
 
-    private function validateNamedParameters(): void
-    {
-        if (self::STRATEGY_REGULAR !== $this->strategy) {
-            $this->setStrategy($this->strategy);
-        }
-
-        if (null !== $this->domain) {
-            $this->setDomain($this->domain);
-        }
-
-        if (null !== $this->customDomain) {
-            $this->setCustomDomain($this->customDomain);
-        }
-
-        if (null !== $this->clientId) {
-            $this->setClientId($this->clientId);
-        }
-
-        if (null !== $this->redirectUri) {
-            $this->setRedirectUri($this->redirectUri);
-        }
-
-        if (null !== $this->clientSecret) {
-            $this->setClientSecret($this->clientSecret);
-        }
-
-        if (null !== $this->audience) {
-            $this->setAudience($this->audience);
-        }
-
-        if (null !== $this->organization) {
-            $this->setOrganization($this->organization);
-        }
-
-        if (!$this->usePkce) {
-            $this->setUsePkce($this->usePkce);
-        }
-
-        if (['openid', 'profile', 'email'] !== $this->scope) {
-            $this->setScope($this->scope);
-        }
-
-        if ('query' !== $this->responseMode) {
-            $this->setResponseMode($this->responseMode);
-        }
-
-        if ('code' !== $this->responseType) {
-            $this->setResponseType($this->responseType);
-        }
-
-        if ('RS256' !== $this->tokenAlgorithm) {
-            $this->setTokenAlgorithm($this->tokenAlgorithm);
-        }
-
-        if (null !== $this->tokenJwksUri) {
-            $this->setTokenJwksUri($this->tokenJwksUri);
-        }
-
-        if (null !== $this->tokenMaxAge) {
-            $this->setTokenMaxAge($this->tokenMaxAge);
-        }
-
-        if (60 !== $this->tokenLeeway) {
-            $this->setTokenLeeway($this->tokenLeeway);
-        }
-
-        if (null !== $this->tokenCache) {
-            $this->setTokenCache($this->tokenCache);
-        }
-
-        if (60 !== $this->tokenCacheTtl) {
-            $this->setTokenCacheTtl($this->tokenCacheTtl);
-        }
-
-        if (null !== $this->httpClient) {
-            $this->setHttpClient($this->httpClient);
-        }
-
-        if (3 !== $this->httpMaxRetries) {
-            $this->setHttpMaxRetries($this->httpMaxRetries);
-        }
-
-        if (null !== $this->httpRequestFactory) {
-            $this->setHttpRequestFactory($this->httpRequestFactory);
-        }
-
-        if (null !== $this->httpResponseFactory) {
-            $this->setHttpResponseFactory($this->httpResponseFactory);
-        }
-
-        if (null !== $this->httpStreamFactory) {
-            $this->setHttpStreamFactory($this->httpStreamFactory);
-        }
-
-        if ($this->httpTelemetry) {
-            $this->setHttpTelemetry($this->httpTelemetry);
-        }
-
-        if (null !== $this->sessionStorage) {
-            $this->setSessionStorage($this->sessionStorage);
-        }
-
-        if ('auth0_session' !== $this->sessionStorageId) {
-            $this->setSessionStorageId($this->sessionStorageId);
-        }
-
-        if (null !== $this->cookieSecret) {
-            $this->setCookieSecret($this->cookieSecret);
-        }
-
-        if (null !== $this->cookieDomain) {
-            $this->setCookieDomain($this->cookieDomain);
-        }
-
-        if (0 !== $this->cookieExpires) {
-            $this->setCookieExpires($this->cookieExpires);
-        }
-
-        if ('/' !== $this->cookiePath) {
-            $this->setCookiePath($this->cookiePath);
-        }
-
-        if ($this->cookieSecure) {
-            $this->setCookieSecure($this->cookieSecure);
-        }
-
-        if (null !== $this->cookieSameSite) {
-            $this->setCookieSameSite($this->cookieSameSite);
-        }
-
-        if (!$this->persistUser) {
-            $this->setPersistUser($this->persistUser);
-        }
-
-        if (!$this->persistIdToken) {
-            $this->setPersistIdToken($this->persistIdToken);
-        }
-
-        if (!$this->persistAccessToken) {
-            $this->setPersistAccessToken($this->persistAccessToken);
-        }
-
-        if (!$this->persistRefreshToken) {
-            $this->setPersistRefreshToken($this->persistRefreshToken);
-        }
-
-        if (null !== $this->transientStorage) {
-            $this->setTransientStorage($this->transientStorage);
-        }
-
-        if ('auth0_transient' !== $this->transientStorageId) {
-            $this->setTransientStorageId($this->transientStorageId);
-        }
-
-        if ($this->queryUserInfo) {
-            $this->setQueryUserInfo($this->queryUserInfo);
-        }
-
-        if (null !== $this->managementToken) {
-            $this->setManagementToken($this->managementToken);
-        }
-
-        if (null !== $this->managementTokenCache) {
-            $this->setManagementTokenCache($this->managementTokenCache);
-        }
-
-        if (null !== $this->eventListenerProvider) {
-            $this->setEventListenerProvider($this->eventListenerProvider);
-        }
-    }
-
     /**
      * Setup SDK validators based on strategy type.
      */
@@ -1353,4 +1245,108 @@ private function validateStateWebApp(): void
             throw \Auth0\SDK\Exception\ConfigurationException::requiresCookieSecret();
         }
     }
+
+    /**
+     * @return array<callable>
+     *
+     * @psalm-suppress MissingClosureParamType
+     */
+    private function getPropertyValidators(): array
+    {
+        return [
+            'strategy' => fn ($value) => is_string($value),
+            'domain' => fn ($value) => is_string($value) || null === $value,
+            'customDomain' => fn ($value) => is_string($value) || null === $value,
+            'clientId' => fn ($value) => is_string($value) || null === $value,
+            'redirectUri' => fn ($value) => is_string($value) || null === $value,
+            'clientSecret' => fn ($value) => is_string($value) || null === $value,
+            'audience' => fn ($value) => is_array($value) || null === $value,
+            'organization' => fn ($value) => is_array($value) || null === $value,
+            'usePkce' => fn ($value) => is_bool($value),
+            'scope' => fn ($value) => is_array($value),
+            'responseMode' => fn ($value) => is_string($value),
+            'responseType' => fn ($value) => is_string($value),
+            'tokenAlgorithm' => fn ($value) => is_string($value),
+            'tokenJwksUri' => fn ($value) => is_string($value) || null === $value,
+            'tokenMaxAge' => fn ($value) => is_int($value) || null === $value,
+            'tokenLeeway' => fn ($value) => is_int($value),
+            'tokenCache' => fn ($value) => $value instanceof CacheItemPoolInterface || null === $value,
+            'tokenCacheTtl' => fn ($value) => is_int($value),
+            'httpClient' => fn ($value) => $value instanceof ClientInterface || null === $value,
+            'httpMaxRetries' => fn ($value) => is_int($value),
+            'httpRequestFactory' => fn ($value) => $value instanceof RequestFactoryInterface || null === $value,
+            'httpResponseFactory' => fn ($value) => $value instanceof ResponseFactoryInterface || null === $value,
+            'httpStreamFactory' => fn ($value) => $value instanceof StreamFactoryInterface || null === $value,
+            'httpTelemetry' => fn ($value) => is_bool($value),
+            'sessionStorage' => fn ($value) => $value instanceof StoreInterface || null === $value,
+            'sessionStorageId' => fn ($value) => is_string($value),
+            'cookieSecret' => fn ($value) => is_string($value) || null === $value,
+            'cookieDomain' => fn ($value) => is_string($value) || null === $value,
+            'cookieExpires' => fn ($value) => is_int($value),
+            'cookiePath' => fn ($value) => is_string($value),
+            'cookieSecure' => fn ($value) => is_bool($value),
+            'cookieSameSite' => fn ($value) => is_string($value) || null === $value,
+            'persistUser' => fn ($value) => is_bool($value),
+            'persistIdToken' => fn ($value) => is_bool($value),
+            'persistAccessToken' => fn ($value) => is_bool($value),
+            'persistRefreshToken' => fn ($value) => is_bool($value),
+            'transientStorage' => fn ($value) => $value instanceof StoreInterface || null === $value,
+            'transientStorageId' => fn ($value) => is_string($value),
+            'queryUserInfo' => fn ($value) => is_bool($value),
+            'managementToken' => fn ($value) => is_string($value) || null === $value,
+            'managementTokenCache' => fn ($value) => $value instanceof CacheItemPoolInterface || null === $value,
+            'eventListenerProvider' => fn ($value) => $value instanceof ListenerProviderInterface || null === $value,
+        ];
+    }
+
+    /**
+     * @return array<mixed>
+     */
+    private function getPropertyDefaults(): array
+    {
+        return [
+            'strategy' => self::STRATEGY_REGULAR,
+            'domain' => null,
+            'customDomain' => null,
+            'clientId' => null,
+            'redirectUri' => null,
+            'clientSecret' => null,
+            'audience' => null,
+            'organization' => null,
+            'usePkce' => true,
+            'scope' => ['openid', 'profile', 'email'],
+            'responseMode' => 'query',
+            'responseType' => 'code',
+            'tokenAlgorithm' => Token::ALGO_RS256,
+            'tokenJwksUri' => null,
+            'tokenMaxAge' => null,
+            'tokenLeeway' => 60,
+            'tokenCache' => null,
+            'tokenCacheTtl' => 60,
+            'httpClient' => null,
+            'httpMaxRetries' => 3,
+            'httpRequestFactory' => null,
+            'httpResponseFactory' => null,
+            'httpStreamFactory' => null,
+            'httpTelemetry' => true,
+            'sessionStorage' => null,
+            'sessionStorageId' => 'auth0_session',
+            'cookieSecret' => null,
+            'cookieDomain' => null,
+            'cookieExpires' => 0,
+            'cookiePath' => '/',
+            'cookieSecure' => false,
+            'cookieSameSite' => null,
+            'persistUser' => true,
+            'persistIdToken' => true,
+            'persistAccessToken' => true,
+            'persistRefreshToken' => true,
+            'transientStorage' => null,
+            'transientStorageId' => 'auth0_transient',
+            'queryUserInfo' => false,
+            'managementToken' => null,
+            'managementTokenCache' => null,
+            'eventListenerProvider' => null,
+        ];
+    }
 }
diff --git a/src/Configuration/SdkState.php b/src/Configuration/SdkState.php
index d99a5348..24fe4840 100644
--- a/src/Configuration/SdkState.php
+++ b/src/Configuration/SdkState.php
@@ -31,12 +31,19 @@ public function __construct(
         public ?array $user = null,
         public ?int $accessTokenExpiration = null
     ) {
-        $configuration = $configuration ?? [];
-        $this->applyConfigurationState($configuration);
+        if (null !== $configuration && [] !== $configuration) {
+            $this->applyConfiguration($configuration);
+        }
+
+        $this->validateProperties();
     }
 
     public function setIdToken(?string $idToken = null): self
     {
+        if (null !== $idToken && '' === trim($idToken)) {
+            $idToken = null;
+        }
+
         $this->idToken = $idToken;
         return $this;
     }
@@ -54,6 +61,10 @@ public function hasIdToken(): bool
 
     public function setAccessToken(?string $accessToken = null): self
     {
+        if (null !== $accessToken && '' === trim($accessToken)) {
+            $accessToken = null;
+        }
+
         $this->accessToken = $accessToken;
         return $this;
     }
@@ -74,6 +85,10 @@ public function hasAccessToken(): bool
      */
     public function setAccessTokenScope(?array $accessTokenScope): self
     {
+        if (null !== $accessTokenScope && [] === $accessTokenScope) {
+            $accessTokenScope = null;
+        }
+
         $this->accessTokenScope = $this->filterArray($accessTokenScope);
         return $this;
     }
@@ -110,6 +125,10 @@ public function pushAccessTokenScope(array|string $scopes): ?array
 
     public function setRefreshToken(?string $refreshToken = null): self
     {
+        if (null !== $refreshToken && '' === trim($refreshToken)) {
+            $refreshToken = null;
+        }
+
         $this->refreshToken = $refreshToken;
         return $this;
     }
@@ -131,6 +150,10 @@ public function hasRefreshToken(): bool
      */
     public function setUser(?array $user): self
     {
+        if (null !== $user && [] === $user) {
+            $user = null;
+        }
+
         $this->user = $user;
         return $this;
     }
@@ -151,6 +174,10 @@ public function hasUser(): bool
 
     public function setAccessTokenExpiration(?int $accessTokenExpiration = null): self
     {
+        if (null !== $accessTokenExpiration && $accessTokenExpiration < 0) {
+            $accessTokenExpiration = null;
+        }
+
         $this->accessTokenExpiration = $accessTokenExpiration;
         return $this;
     }
@@ -165,4 +192,36 @@ public function hasAccessTokenExpiration(): bool
     {
         return null !== $this->accessTokenExpiration;
     }
+
+    /**
+     * @return array<callable>
+     *
+     * @psalm-suppress MissingClosureParamType
+     */
+    private function getPropertyValidators(): array
+    {
+        return [
+            'idToken' => fn ($value) => is_string($value) || null === $value,
+            'accessToken' => fn ($value) => is_string($value) || null === $value,
+            'accessTokenScope' => fn ($value) => is_array($value) || null === $value,
+            'refreshToken' => fn ($value) => is_string($value) || null === $value,
+            'user' => fn ($value) => is_array($value) || null === $value,
+            'accessTokenExpiration' => fn ($value) => is_int($value) || null === $value,
+        ];
+    }
+
+    /**
+     * @return array<mixed>
+     */
+    private function getPropertyDefaults(): array
+    {
+        return [
+            'idToken' => null,
+            'accessToken' => null,
+            'accessTokenScope' => null,
+            'refreshToken' => null,
+            'user' => null,
+            'accessTokenExpiration' => null,
+        ];
+    }
 }
diff --git a/src/Mixins/ConfigurableMixin.php b/src/Mixins/ConfigurableMixin.php
index 772c8c76..5b1cbed8 100644
--- a/src/Mixins/ConfigurableMixin.php
+++ b/src/Mixins/ConfigurableMixin.php
@@ -13,34 +13,81 @@ trait ConfigurableMixin
      *
      * @psalm-suppress MissingClosureParamType,MissingClosureReturnType
      */
-    private function applyConfigurationState(?array $configuration): self
+    private function applyConfiguration(?array $configuration): self
     {
         if (null === $configuration) {
             return $this;
         }
 
-        foreach ($configuration as $configurationKey => $configurationValue) {
-            if (property_exists($this, $configurationKey)) {
-                $method = 'set' . ucfirst($configurationKey);
+        $validators = $this->getPropertyValidators();
+        $defaults = $this->getPropertyDefaults();
 
-                if (method_exists($this, $method)) {
-                    $callback = function ($configurationValue) use ($method) {
-                        // @phpstan-ignore-next-line
-                        return $this->$method($configurationValue);
-                    };
+        foreach ($configuration as $configKey => $configuredValue) {
+            if (! property_exists($this, $configKey) || ! array_key_exists($configKey, $defaults)) {
+                continue;
+            }
 
-                    call_user_func($callback, $configurationValue);
-                    continue;
-                }
+            if (! isset($validators[$configKey]) || ! is_callable($validators[$configKey])) {
+                throw \Auth0\SDK\Exception\ConfigurationException::validationFailed($configKey);
+            }
 
+            if ($validators[$configKey]($configuredValue) === false) {
+                throw \Auth0\SDK\Exception\ConfigurationException::validationFailed($configKey);
+            }
+
+            $method = 'set' . ucfirst($configKey);
+
+            if (method_exists($this, $method)) {
                 // @phpstan-ignore-next-line
-                $this->$configurationKey = $configurationValue;
+                $callback = function ($configuredValue) use ($method) {
+                    // @phpstan-ignore-next-line
+                    return $this->$method($configuredValue);
+                };
+
+                call_user_func($callback, $configuredValue);
+                continue;
             }
+
+            // @phpstan-ignore-next-line
+            $this->$configKey = $configuredValue;
         }
 
         return $this;
     }
 
+    /**
+     * @psalm-suppress MissingClosureParamType,MissingClosureReturnType
+     */
+    private function validateProperties(): void
+    {
+        $defaults = $this->getPropertyDefaults();
+
+        foreach ($defaults as $configKey => $defaultValue) {
+            if (! property_exists($this, $configKey)) {
+                continue;
+            }
+
+            // @phpstan-ignore-next-line
+            if ($this->$configKey === $defaultValue) {
+                continue;
+            }
+
+            $method = 'set' . ucfirst($configKey);
+
+            if (method_exists($this, $method)) {
+                // @phpstan-ignore-next-line
+                $callback = function ($value) use ($method) {
+                    // @phpstan-ignore-next-line
+                    return $this->$method($value);
+                };
+
+                // @phpstan-ignore-next-line
+                call_user_func($callback, $this->$configKey);
+                continue;
+            }
+        }
+    }
+
     /**
      * @param mixed $value A value to compare against NULL.
      * @param null|Throwable $throwable Optional. A Throwable exception to raise if $value is NULL.
diff --git a/tests/Unit/API/AuthenticationTest.php b/tests/Unit/API/AuthenticationTest.php
index 995548f9..698b0b4f 100644
--- a/tests/Unit/API/AuthenticationTest.php
+++ b/tests/Unit/API/AuthenticationTest.php
@@ -30,7 +30,7 @@
 
 test('__construct() accepts a configuration as an array', function(): void {
     $auth = new Authentication([
-        'strategy' => 'api',
+        'strategy' => SdkConfiguration::STRATEGY_API,
         'domain' => MockDomain::valid(),
         'audience' => [uniqid()]
     ]);
diff --git a/tests/Unit/API/Management/ManagementEndpointTest.php b/tests/Unit/API/Management/ManagementEndpointTest.php
index 22f88b18..ae9d3ebd 100644
--- a/tests/Unit/API/Management/ManagementEndpointTest.php
+++ b/tests/Unit/API/Management/ManagementEndpointTest.php
@@ -17,7 +17,7 @@
 
 beforeEach(function(): void {
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'domain' => MockDomain::valid()
     ]);
 
diff --git a/tests/Unit/Configuration/SdkConfigurationTest.php b/tests/Unit/Configuration/SdkConfigurationTest.php
index 40c87d9a..125822a5 100644
--- a/tests/Unit/Configuration/SdkConfigurationTest.php
+++ b/tests/Unit/Configuration/SdkConfigurationTest.php
@@ -46,7 +46,7 @@
 test('__construct() does not accept invalid types from configuration array', function(): void
 {
     $config = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'domain' => MockDomain::invalid(),
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, sprintf(\Auth0\SDK\Exception\ConfigurationException::MSG_VALIDATION_FAILED, 'domain'));
@@ -74,7 +74,7 @@
         'clientId' => $clientId,
         'redirectUri' => $redirectUri,
     ]);
-})->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_DOMAIN);
+})->throws(\Auth0\SDK\Exception\ConfigurationException::class, sprintf(\Auth0\SDK\Exception\ConfigurationException::MSG_VALIDATION_FAILED, 'domain'));
 
 test('__construct() throws an exception if domain is an invalid uri', function(): void {
     $cookieSecret = uniqid();
@@ -143,7 +143,7 @@
         'redirectUri' => $redirectUri,
         'tokenLeeway' => 'TEST'
     ]);
-})->throws(\TypeError::class);
+})->throws(\Auth0\SDK\Exception\ConfigurationException::class, sprintf(\Auth0\SDK\Exception\ConfigurationException::MSG_VALIDATION_FAILED, 'tokenLeeway'));
 
 test('successfully updates values', function(): void
 {
@@ -192,7 +192,7 @@
 test('a non-existent array value is ignored', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'domain' => MockDomain::valid(),
         'clientId' => uniqid(),
         'organization' => [],
@@ -214,15 +214,12 @@
 
 test('a `webapp` strategy requires a domain', function(): void
 {
-    $sdk = new SdkConfiguration([
-        'strategy' => 'webapp',
-    ]);
+    $sdk = new SdkConfiguration();
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_DOMAIN);
 
 test('a `webapp` strategy requires a client id', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'webapp',
         'domain' => MockDomain::valid()
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_CLIENT_ID);
@@ -230,7 +227,6 @@
 test('a `webapp` strategy requires a client secret when HS256 is used', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'webapp',
         'domain' => MockDomain::valid(),
         'clientId' => uniqid(),
         'tokenAlgorithm' => 'HS256'
@@ -240,14 +236,14 @@
 test('a `api` strategy requires a domain', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'api',
+        'strategy' => SdkConfiguration::STRATEGY_API,
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_DOMAIN);
 
 test('a `api` strategy requires an audience', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'api',
+        'strategy' => SdkConfiguration::STRATEGY_API,
         'domain' => MockDomain::valid()
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_AUDIENCE);
@@ -255,14 +251,14 @@
 test('a `management` strategy requires a domain', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'management'
+        'strategy' => SdkConfiguration::STRATEGY_MANAGEMENT_API
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_DOMAIN);
 
 test('a `management` strategy requires a client id if a management token is not provided', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'management',
+        'strategy' => SdkConfiguration::STRATEGY_MANAGEMENT_API,
         'domain' => MockDomain::valid()
     ]);
 })->throws(\Auth0\SDK\Exception\ConfigurationException::class, \Auth0\SDK\Exception\ConfigurationException::MSG_REQUIRES_CLIENT_ID);
@@ -270,7 +266,7 @@
 test('a `management` strategy requires a client secret if a management token is not provided', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'management',
+        'strategy' => SdkConfiguration::STRATEGY_MANAGEMENT_API,
         'domain' => MockDomain::valid(),
         'clientId' => uniqid()
     ]);
@@ -279,7 +275,7 @@
 test('a `management` strategy does not require a client id or secret if a management token is provided', function(): void
 {
     $sdk = new SdkConfiguration([
-        'strategy' => 'management',
+        'strategy' => SdkConfiguration::STRATEGY_MANAGEMENT_API,
         'domain' => MockDomain::valid(),
         'managementToken' => uniqid()
     ]);
diff --git a/tests/Unit/Store/CookieStoreTest.php b/tests/Unit/Store/CookieStoreTest.php
index 4b3bd053..52100541 100644
--- a/tests/Unit/Store/CookieStoreTest.php
+++ b/tests/Unit/Store/CookieStoreTest.php
@@ -14,7 +14,7 @@
     $this->cookieSecret = uniqid() . bin2hex(random_bytes(32));
 
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'cookieSecret' => $this->cookieSecret
     ]);
 
@@ -158,7 +158,7 @@
 
 test('encrypt() throws an exception if a cookie secret is not configured', function(): void {
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none'
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
     ]);
 
     $this->store = new CookieStore($this->configuration, $this->namespace);
@@ -168,7 +168,7 @@
 
 test('decrypt() throws an exception if a cookie secret is not configured', function(array $state): void {
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none'
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
     ]);
 
     $this->store = new CookieStore($this->configuration, $this->namespace);
diff --git a/tests/Unit/Store/Psr14StoreTest.php b/tests/Unit/Store/Psr14StoreTest.php
index 8e6c7cf2..f6a4e613 100644
--- a/tests/Unit/Store/Psr14StoreTest.php
+++ b/tests/Unit/Store/Psr14StoreTest.php
@@ -18,7 +18,7 @@
     $this->listener = new MockPsr14StoreListener();
 
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'eventListenerProvider' => $this->listener->setup()
     ]);
 });
diff --git a/tests/Unit/Token/ParserTest.php b/tests/Unit/Token/ParserTest.php
index 92bee264..bd8dd943 100644
--- a/tests/Unit/Token/ParserTest.php
+++ b/tests/Unit/Token/ParserTest.php
@@ -14,7 +14,7 @@
     $this->cache = new ArrayAdapter();
 
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'tokenCache' => $this->cache
     ]);
 });
diff --git a/tests/Unit/TokenTest.php b/tests/Unit/TokenTest.php
index bdcbd407..c6b4e8f3 100644
--- a/tests/Unit/TokenTest.php
+++ b/tests/Unit/TokenTest.php
@@ -14,7 +14,7 @@
     $this->cache = new ArrayAdapter();
 
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'tokenCache' => $this->cache
     ]);
 });
diff --git a/tests/Unit/Utility/EventDispatcherTest.php b/tests/Unit/Utility/EventDispatcherTest.php
index ebcb8275..6a170c6e 100644
--- a/tests/Unit/Utility/EventDispatcherTest.php
+++ b/tests/Unit/Utility/EventDispatcherTest.php
@@ -27,7 +27,7 @@ public function isPropagationStopped(): bool {
     });
 
     $configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'eventListenerProvider' => $listener
     ]);
 
diff --git a/tests/Unit/Utility/HttpRequestTest.php b/tests/Unit/Utility/HttpRequestTest.php
index 49397d51..7724b4cd 100644
--- a/tests/Unit/Utility/HttpRequestTest.php
+++ b/tests/Unit/Utility/HttpRequestTest.php
@@ -13,7 +13,7 @@
 
 beforeEach(function(): void {
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
         'domain' => MockDomain::valid(),
     ]);
 });
diff --git a/tests/Unit/Utility/TransientStoreHandlerTest.php b/tests/Unit/Utility/TransientStoreHandlerTest.php
index aeb55666..8c928d5d 100644
--- a/tests/Unit/Utility/TransientStoreHandlerTest.php
+++ b/tests/Unit/Utility/TransientStoreHandlerTest.php
@@ -5,6 +5,7 @@
 use Auth0\SDK\Configuration\SdkConfiguration;
 use Auth0\SDK\Store\MemoryStore;
 use Auth0\SDK\Utility\TransientStoreHandler;
+use Auth0\Tests\Utilities\MockDomain;
 
 uses()->group('utility', 'utility.transient_store_handler');
 
@@ -12,7 +13,7 @@
     $this->namespace = uniqid();
 
     $this->configuration = new SdkConfiguration([
-        'strategy' => 'none',
+        'strategy' => SdkConfiguration::STRATEGY_NONE,
     ]);
 
     $this->store = new MemoryStore($this->configuration, $this->namespace);