diff --git a/app/backend/src/main/kotlin/de/fraunhofer/iem/app/toolRun/service/ToolRunService.kt b/app/backend/src/main/kotlin/de/fraunhofer/iem/app/toolRun/service/ToolRunService.kt
index 05336fa470a90d5d1fa204dab936b1c8859b504b..b62b6c0a500946bf308f88328a8a4296272830d5 100644
--- a/app/backend/src/main/kotlin/de/fraunhofer/iem/app/toolRun/service/ToolRunService.kt
+++ b/app/backend/src/main/kotlin/de/fraunhofer/iem/app/toolRun/service/ToolRunService.kt
@@ -81,14 +81,11 @@ class ToolRunService(
                 val repoDetailsDto = repositoryDetailsService.getRepositoryDetails(projectId)
                 val rawValueRepoKpis =
                     VcsAdapter.transformDataToKpi(repoDetailsDto)
+                        .filterIsInstance<AdapterResult.Success>()
+                        .map { it.rawValueKpi }
 
-                val result = if (rawValueRepoKpis is AdapterResult.Success) {
-                    listOf(rawValueRepoKpis.rawValueKpi)
-                } else {
-                    listOf()
-                }
 
-                Pair(repositoryDetailsService.getToolDto(), result)
+                Pair(repositoryDetailsService.getToolDto(), rawValueRepoKpis)
             },
 
             async {
diff --git a/kpi-calculator/adapter/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/adapter/KpiAdapter.kt b/kpi-calculator/adapter/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/adapter/KpiAdapter.kt
index ab93079a772342ea01d4fdee6923686cb7cbd843..2ae04b8d4ec83105309dd292d5275342bcd2bd08 100644
--- a/kpi-calculator/adapter/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/adapter/KpiAdapter.kt
+++ b/kpi-calculator/adapter/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/adapter/KpiAdapter.kt
@@ -5,5 +5,5 @@ import de.fraunhofer.iem.kpiCalculator.model.adapter.AdapterResult
 
 interface KpiAdapter<T> {
     fun transformDataToKpi(data: List<T>): List<AdapterResult>
-    fun transformDataToKpi(data: T): AdapterResult = transformDataToKpi(listOf(data)).first()
+    fun transformDataToKpi(data: T): List<AdapterResult> = transformDataToKpi(listOf(data))
 }
diff --git a/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/KpiCalculator.kt b/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/KpiCalculator.kt
index 8ae82a12fcb80cbdfe37bd96f1f8187b28060a78..7d34a34a0f390067c0456678b75e38a7454c5a68 100644
--- a/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/KpiCalculator.kt
+++ b/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/KpiCalculator.kt
@@ -61,7 +61,7 @@ object KpiCalculator {
         depthFirstTraversal(
             node = calculationRoot
         ) { currentNode ->
-            val correspondingRawValue = kindToValues[currentNode.kind]
+            val correspondingRawValue = kindToValues[currentNode.kpiId]
             val parent = currentNode.parent
 
             if (!correspondingRawValue.isNullOrEmpty() && parent != null) {
@@ -77,7 +77,7 @@ object KpiCalculator {
 
                 val rawValueNodes = correspondingRawValue.map { rawValue ->
                     val newNode = KpiCalculationNode(
-                        kind = rawValue.kind,
+                        kpiId = rawValue.kind,
                         calculationStrategy = KpiStrategyId.RAW_VALUE_STRATEGY,
                         parent = parent
                     )
diff --git a/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/hierarchy/KpiCalculationNode.kt b/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/hierarchy/KpiCalculationNode.kt
index 252bfbfe6c9c9e272f89f6030e7234ea66e2b11a..f4d3a8c8fa3ed66b998053bc7b81a999dd9d0102 100644
--- a/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/hierarchy/KpiCalculationNode.kt
+++ b/kpi-calculator/core/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/core/hierarchy/KpiCalculationNode.kt
@@ -12,7 +12,7 @@ import de.fraunhofer.iem.kpiCalculator.model.kpi.hierarchy.KpiResultNode
 
 
 internal class KpiCalculationNode(
-    val kind: KpiId,
+    val kpiId: KpiId,
     val calculationStrategy: KpiStrategyId,
     val parent: KpiCalculationNode?
 ) {
@@ -96,7 +96,7 @@ internal class KpiCalculationNode(
     companion object {
         fun to(node: KpiCalculationNode): KpiResultNode {
             return KpiResultNode(
-                kpiId = node.kind,
+                kpiId = node.kpiId,
                 strategyType = node.calculationStrategy,
                 kpiResult = node.result,
                 children = node.hierarchyEdges.map {
@@ -116,7 +116,7 @@ internal class KpiCalculationNode(
         private fun from(node: KpiNode, parent: KpiCalculationNode? = null): KpiCalculationNode {
 
             val calcNode =
-                KpiCalculationNode(kind = node.kpiId, parent = parent, calculationStrategy = node.strategyType)
+                KpiCalculationNode(kpiId = node.kpiId, parent = parent, calculationStrategy = node.strategyType)
             val children = node.children.map { child ->
                 KpiHierarchyEdge(
                     to = from(child.target, calcNode),
diff --git a/kpi-calculator/model/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/model/kpi/hierarchy/KpiHierarchy.kt b/kpi-calculator/model/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/model/kpi/hierarchy/KpiHierarchy.kt
index 0505b5f1ff3c0cd4f591f43e924a110e24819f34..efc9d7dd862847137e4203d071be9d40ec8a3697 100644
--- a/kpi-calculator/model/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/model/kpi/hierarchy/KpiHierarchy.kt
+++ b/kpi-calculator/model/src/main/kotlin/de/fraunhofer/iem/kpiCalculator/model/kpi/hierarchy/KpiHierarchy.kt
@@ -8,7 +8,7 @@ val SCHEMA_VERSIONS: Array<String> = arrayOf(
     "1.0.0"
 ).sortedArray()
 
-//TODO: add Hierarchy Validator
+//XXX: add Hierarchy Validator
 @Serializable
 data class KpiHierarchy private constructor(val rootNode: KpiNode, val schemaVersion: String) {
     companion object {
@@ -22,6 +22,7 @@ data class KpiNode(val kpiId: KpiId, val strategyType: KpiStrategyId, val childr
 @Serializable
 data class KpiEdge(val target: KpiNode, val weight: Double)
 
+//TODO: extract this in a separate file
 @Serializable
 data class KpiResultHierarchy private constructor(val rootNode: KpiResultNode, val schemaVersion: String) {
     companion object {