diff --git a/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClient.scala b/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClient.scala
index 4e089d9..f170315 100644
--- a/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClient.scala
+++ b/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClient.scala
@@ -1,12 +1,9 @@
 package io.cardell.openfeature
 
-import cats.syntax.all._
 import io.cardell.openfeature.provider.ProviderMetadata
-import io.cardell.openfeature.provider.Provider
-import cats.Monad
 
 // TODO implement circe
-trait ObjectDecoder[A]
+trait StructureDecoder[A]
 
 case class EvaluationOptions()
 object EvaluationOptions {
@@ -121,223 +118,51 @@ trait FeatureClient[F[_]] {
       options: EvaluationOptions
   ): F[Double]
 
-  def getObjectValue[A: ObjectDecoder](flagKey: String, default: A): F[A]
-  def getObjectValue[A: ObjectDecoder](
+  def getDoubleDetails(
       flagKey: String,
-      default: A,
-      context: EvaluationContext
-  ): F[A]
-  def getObjectValue[A: ObjectDecoder](
-      flagKey: String,
-      default: A,
-      context: EvaluationContext,
-      options: EvaluationOptions
-  ): F[A]
-}
-
-protected final class OpenFeatureClient[F[_]: Monad](
-    provider: Provider[F],
-    clientEvaluationContext: EvaluationContext
-) extends FeatureClient[F] {
-
-  override def providerMetadata: ProviderMetadata = provider.metadata
-
-  override def evaluationContext: EvaluationContext = clientEvaluationContext
-
-  override def withEvaluationContext(
-      context: EvaluationContext
-  ): FeatureClient[F] =
-    new OpenFeatureClient[F](provider, clientEvaluationContext ++ context)
-
-  // override def hooks: List[Hook] = ???
-  // override def withHook(hook: Hook): FeatureClient[F] = ???
-  // override def withHooks(hooks: List[Hook]): FeatureClient[F] = ???
-
-  override def getBooleanValue(flagKey: String, default: Boolean): F[Boolean] =
-    getBooleanValue(flagKey, default, EvaluationContext.empty)
-
-  override def getBooleanValue(
-      flagKey: String,
-      default: Boolean,
-      context: EvaluationContext
-  ): F[Boolean] =
-    getBooleanValue(
-      flagKey,
-      default,
-      context,
-      EvaluationOptions.Defaults
-    )
-
-  override def getBooleanValue(
-      flagKey: String,
-      default: Boolean,
-      context: EvaluationContext,
-      options: EvaluationOptions // TODO handle options
-  ): F[Boolean] =
-    getBooleanDetails(flagKey, default, context, options)
-      .map(_.value)
-
-  override def getBooleanDetails(
-      flagKey: String,
-      default: Boolean
-  ): F[EvaluationDetails[Boolean]] =
-    getBooleanDetails(flagKey, default, EvaluationContext.empty)
-
-  override def getBooleanDetails(
-      flagKey: String,
-      default: Boolean,
-      context: EvaluationContext
-  ): F[EvaluationDetails[Boolean]] =
-    getBooleanDetails(flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getBooleanDetails(
-      flagKey: String,
-      default: Boolean,
-      context: EvaluationContext,
-      options: EvaluationOptions
-  ): F[EvaluationDetails[Boolean]] =
-    provider
-      .resolveBooleanValue(
-        flagKey,
-        default,
-        clientEvaluationContext ++ context
-      )
-      .map(EvaluationDetails[Boolean](flagKey, _))
-
-  override def getStringValue(flagKey: String, default: String): F[String] =
-    getStringValue(flagKey, default, EvaluationContext.empty)
-
-  override def getStringValue(
+      default: Double
+  ): F[EvaluationDetails[Double]]
+  def getDoubleDetails(
       flagKey: String,
-      default: String,
-      context: EvaluationContext
-  ): F[String] =
-    getStringValue(
-      flagKey,
-      default,
-      context,
-      EvaluationOptions.Defaults
-    )
-
-  override def getStringValue(
-      flagKey: String,
-      default: String,
-      context: EvaluationContext,
-      options: EvaluationOptions
-  ): F[String] =
-    getStringDetails(flagKey, default, context, EvaluationOptions.Defaults)
-      .map(_.value)
-
-  override def getStringDetails(
-      flagKey: String,
-      default: String
-  ): F[EvaluationDetails[String]] =
-    getStringDetails(flagKey, default, EvaluationContext.empty)
-
-  override def getStringDetails(
-      flagKey: String,
-      default: String,
-      context: EvaluationContext
-  ): F[EvaluationDetails[String]] =
-    getStringDetails(flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getStringDetails(
-      flagKey: String,
-      default: String,
-      context: EvaluationContext,
-      options: EvaluationOptions
-  ): F[EvaluationDetails[String]] =
-    provider
-      .resolveStringValue(flagKey, default, clientEvaluationContext ++ context)
-      .map(EvaluationDetails[String](flagKey, _))
-
-  override def getIntValue(flagKey: String, default: Int): F[Int] =
-    getIntValue(flagKey, default, EvaluationContext.empty)
-
-  override def getIntValue(
-      flagKey: String,
-      default: Int,
+      default: Double,
       context: EvaluationContext
-  ): F[Int] = getIntValue(flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getIntValue(
+  ): F[EvaluationDetails[Double]]
+  def getDoubleDetails(
       flagKey: String,
-      default: Int,
+      default: Double,
       context: EvaluationContext,
       options: EvaluationOptions
-  ): F[Int] =
-    getIntDetails(flagKey, default, context, options)
-      .map(_.value)
+  ): F[EvaluationDetails[Double]]
 
-  override def getIntDetails(
+  def getStructureValue[A: StructureDecoder](
       flagKey: String,
-      default: Int
-  ): F[EvaluationDetails[Int]] =
-    getIntDetails(flagKey, default, EvaluationContext.empty)
-
-  override def getIntDetails(
-      flagKey: String,
-      default: Int,
-      context: EvaluationContext
-  ): F[EvaluationDetails[Int]] =
-    getIntDetails(flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getIntDetails(
-      flagKey: String,
-      default: Int,
-      context: EvaluationContext,
-      options: EvaluationOptions
-  ): F[EvaluationDetails[Int]] =
-    provider
-      .resolveIntValue(
-        flagKey,
-        default,
-        clientEvaluationContext ++ context
-      )
-      .map(EvaluationDetails[Int](flagKey, _))
-
-  override def getDoubleValue(flagKey: String, default: Double): F[Double] =
-    getDoubleValue(flagKey, default, EvaluationContext.empty)
-
-  override def getDoubleValue(
+      default: A
+  ): F[A]
+  def getStructureValue[A: StructureDecoder](
       flagKey: String,
-      default: Double,
+      default: A,
       context: EvaluationContext
-  ): F[Double] =
-    getDoubleValue(flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getDoubleValue(
+  ): F[A]
+  def getStructureValue[A: StructureDecoder](
       flagKey: String,
-      default: Double,
+      default: A,
       context: EvaluationContext,
       options: EvaluationOptions
-  ): F[Double] =
-    provider
-      .resolveDoubleValue(
-        flagKey,
-        default,
-        clientEvaluationContext ++ context
-      )
-      .map(_.value)
+  ): F[A]
 
-  override def getObjectValue[A: ObjectDecoder](
+  def getStructureDetails[A: StructureDecoder](
       flagKey: String,
       default: A
-  ): F[A] =
-    getObjectValue[A](flagKey, default, EvaluationContext.empty)
-
-  override def getObjectValue[A: ObjectDecoder](
+  ): F[EvaluationDetails[A]]
+  def getStructureDetails[A: StructureDecoder](
       flagKey: String,
       default: A,
       context: EvaluationContext
-  ): F[A] =
-    getObjectValue[A](flagKey, default, context, EvaluationOptions.Defaults)
-
-  override def getObjectValue[A: ObjectDecoder](
+  ): F[EvaluationDetails[A]]
+  def getStructureDetails[A: StructureDecoder](
       flagKey: String,
       default: A,
       context: EvaluationContext,
       options: EvaluationOptions
-  ): F[A] =
-    getObjectValue[A](flagKey, default, clientEvaluationContext ++ context)
+  ): F[EvaluationDetails[A]]
 }
diff --git a/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClientImpl.scala b/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClientImpl.scala
new file mode 100644
index 0000000..6f7d81d
--- /dev/null
+++ b/open-feature/sdk/src/main/scala/io/cardell/openfeature/FeatureClientImpl.scala
@@ -0,0 +1,261 @@
+package io.cardell.openfeature
+
+import cats.Monad
+import cats.syntax.all._
+import io.cardell.openfeature.provider.Provider
+import io.cardell.openfeature.provider.ProviderMetadata
+
+protected[openfeature] final class FeatureClientImpl[F[_]: Monad](
+    provider: Provider[F],
+    clientEvaluationContext: EvaluationContext
+) extends FeatureClient[F] {
+
+  override def providerMetadata: ProviderMetadata = provider.metadata
+
+  override def evaluationContext: EvaluationContext = clientEvaluationContext
+
+  override def withEvaluationContext(
+      context: EvaluationContext
+  ): FeatureClient[F] =
+    new FeatureClientImpl[F](provider, clientEvaluationContext ++ context)
+
+  // override def hooks: List[Hook] = ???
+  // override def withHook(hook: Hook): FeatureClient[F] = ???
+  // override def withHooks(hooks: List[Hook]): FeatureClient[F] = ???
+
+  override def getBooleanValue(flagKey: String, default: Boolean): F[Boolean] =
+    getBooleanValue(flagKey, default, EvaluationContext.empty)
+
+  override def getBooleanValue(
+      flagKey: String,
+      default: Boolean,
+      context: EvaluationContext
+  ): F[Boolean] =
+    getBooleanValue(
+      flagKey,
+      default,
+      context,
+      EvaluationOptions.Defaults
+    )
+
+  override def getBooleanValue(
+      flagKey: String,
+      default: Boolean,
+      context: EvaluationContext,
+      options: EvaluationOptions // TODO handle options
+  ): F[Boolean] =
+    getBooleanDetails(flagKey, default, context, options)
+      .map(_.value)
+
+  override def getBooleanDetails(
+      flagKey: String,
+      default: Boolean
+  ): F[EvaluationDetails[Boolean]] =
+    getBooleanDetails(flagKey, default, EvaluationContext.empty)
+
+  override def getBooleanDetails(
+      flagKey: String,
+      default: Boolean,
+      context: EvaluationContext
+  ): F[EvaluationDetails[Boolean]] =
+    getBooleanDetails(flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getBooleanDetails(
+      flagKey: String,
+      default: Boolean,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[EvaluationDetails[Boolean]] =
+    provider
+      .resolveBooleanValue(
+        flagKey,
+        default,
+        clientEvaluationContext ++ context
+      )
+      .map(EvaluationDetails[Boolean](flagKey, _))
+
+  override def getStringValue(flagKey: String, default: String): F[String] =
+    getStringValue(flagKey, default, EvaluationContext.empty)
+
+  override def getStringValue(
+      flagKey: String,
+      default: String,
+      context: EvaluationContext
+  ): F[String] =
+    getStringValue(
+      flagKey,
+      default,
+      context,
+      EvaluationOptions.Defaults
+    )
+
+  override def getStringValue(
+      flagKey: String,
+      default: String,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[String] =
+    getStringDetails(flagKey, default, context, EvaluationOptions.Defaults)
+      .map(_.value)
+
+  override def getStringDetails(
+      flagKey: String,
+      default: String
+  ): F[EvaluationDetails[String]] =
+    getStringDetails(flagKey, default, EvaluationContext.empty)
+
+  override def getStringDetails(
+      flagKey: String,
+      default: String,
+      context: EvaluationContext
+  ): F[EvaluationDetails[String]] =
+    getStringDetails(flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getStringDetails(
+      flagKey: String,
+      default: String,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[EvaluationDetails[String]] =
+    provider
+      .resolveStringValue(flagKey, default, clientEvaluationContext ++ context)
+      .map(EvaluationDetails[String](flagKey, _))
+
+  override def getIntValue(flagKey: String, default: Int): F[Int] =
+    getIntValue(flagKey, default, EvaluationContext.empty)
+
+  override def getIntValue(
+      flagKey: String,
+      default: Int,
+      context: EvaluationContext
+  ): F[Int] = getIntValue(flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getIntValue(
+      flagKey: String,
+      default: Int,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[Int] =
+    getIntDetails(flagKey, default, context, options)
+      .map(_.value)
+
+  override def getIntDetails(
+      flagKey: String,
+      default: Int
+  ): F[EvaluationDetails[Int]] =
+    getIntDetails(flagKey, default, EvaluationContext.empty)
+
+  override def getIntDetails(
+      flagKey: String,
+      default: Int,
+      context: EvaluationContext
+  ): F[EvaluationDetails[Int]] =
+    getIntDetails(flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getIntDetails(
+      flagKey: String,
+      default: Int,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[EvaluationDetails[Int]] =
+    provider
+      .resolveIntValue(
+        flagKey,
+        default,
+        clientEvaluationContext ++ context
+      )
+      .map(EvaluationDetails[Int](flagKey, _))
+
+  override def getDoubleValue(flagKey: String, default: Double): F[Double] =
+    getDoubleValue(flagKey, default, EvaluationContext.empty)
+
+  override def getDoubleValue(
+      flagKey: String,
+      default: Double,
+      context: EvaluationContext
+  ): F[Double] =
+    getDoubleValue(flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getDoubleValue(
+      flagKey: String,
+      default: Double,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[Double] =
+    provider
+      .resolveDoubleValue(
+        flagKey,
+        default,
+        clientEvaluationContext ++ context
+      )
+      .map(_.value)
+
+  override def getDoubleDetails(
+      flagKey: String,
+      default: Double
+  ): F[EvaluationDetails[Double]] = ???
+  override def getDoubleDetails(
+      flagKey: String,
+      default: Double,
+      context: EvaluationContext
+  ): F[EvaluationDetails[Double]] = ???
+  override def getDoubleDetails(
+      flagKey: String,
+      default: Double,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[EvaluationDetails[Double]] = ???
+
+  override def getStructureValue[A: StructureDecoder](
+      flagKey: String,
+      default: A
+  ): F[A] =
+    getStructureValue[A](flagKey, default, EvaluationContext.empty)
+
+  override def getStructureValue[A: StructureDecoder](
+      flagKey: String,
+      default: A,
+      context: EvaluationContext
+  ): F[A] =
+    getStructureValue[A](flagKey, default, context, EvaluationOptions.Defaults)
+
+  override def getStructureValue[A: StructureDecoder](
+      flagKey: String,
+      default: A,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[A] =
+    getStructureDetails[A](flagKey, default, context)
+      .map(_.value)
+
+  override def getStructureDetails[A: StructureDecoder](
+      flagKey: String,
+      default: A
+  ): F[EvaluationDetails[A]] =
+    getStructureDetails[A](flagKey, default, EvaluationContext.empty)
+  override def getStructureDetails[A: StructureDecoder](
+      flagKey: String,
+      default: A,
+      context: EvaluationContext
+  ): F[EvaluationDetails[A]] =
+    getStructureDetails[A](
+      flagKey,
+      default,
+      context,
+      EvaluationOptions.Defaults
+    )
+
+  override def getStructureDetails[A: StructureDecoder](
+      flagKey: String,
+      default: A,
+      context: EvaluationContext,
+      options: EvaluationOptions
+  ): F[EvaluationDetails[A]] =
+    provider
+      .resolveStructureValue[A](
+        flagKey,
+        default,
+        clientEvaluationContext ++ context
+      )
+      .map(EvaluationDetails(flagKey, _))
+}
diff --git a/open-feature/sdk/src/main/scala/io/cardell/openfeature/OpenFeature.scala b/open-feature/sdk/src/main/scala/io/cardell/openfeature/OpenFeature.scala
index 97a20af..c63cabc 100644
--- a/open-feature/sdk/src/main/scala/io/cardell/openfeature/OpenFeature.scala
+++ b/open-feature/sdk/src/main/scala/io/cardell/openfeature/OpenFeature.scala
@@ -15,5 +15,5 @@ trait OpenFeature[F[_]] {
 protected[openfeature] class OpenFeatureSdk[F[_]: Monad](provider: Provider[F])
     extends OpenFeature[F] {
   def client: F[FeatureClient[F]] =
-    new OpenFeatureClient[F](provider, EvaluationContext.empty).pure[F].widen
+    new FeatureClientImpl[F](provider, EvaluationContext.empty).pure[F].widen
 }