diff --git a/build.gradle.kts b/build.gradle.kts
index b2f1ffc..f68bb47 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -146,7 +146,7 @@ kotlin {
     commonTest {
       dependencies {
         implementation(libs.kotlin.test)
-        implementation(libs.kotest.assertions.core)
+        implementation(libs.xemantic.kotlin.test)
         implementation(libs.kotest.assertions.json)
         implementation(libs.kotlinx.datetime)
         implementation(libs.bignum)
@@ -201,10 +201,9 @@ tasks.withType<Test> {
 }
 
 powerAssert {
-  // power assert temporarily switched off for kotest, since it stopped working with kotlin 2.1
-//  functions = listOf(
-//    "io.kotest.matchers.shouldBe"
-//  )
+  functions = listOf(
+    "com.xemantic.kotlin.test.have"
+  )
 }
 
 // https://kotlinlang.org/docs/dokka-migration.html#adjust-configuration-options
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index c0713ff..9ac816b 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -5,6 +5,9 @@ javaTarget = "17"
 kotlin = "2.1.0"
 kotlinxSerialization = "1.7.3"
 kotlinxDatetime = "0.6.1"
+
+xemanticKotlinTest = "0.1.1"
+
 kotest = "6.0.0.M1"
 
 bignum = "0.3.10"
@@ -20,7 +23,8 @@ kotlin-test = { module = "org.jetbrains.kotlin:kotlin-test", version.ref = "kotl
 kotlinx-serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "kotlinxSerialization" }
 kotlinx-datetime = { module="org.jetbrains.kotlinx:kotlinx-datetime", version.ref="kotlinxDatetime" }
 
-kotest-assertions-core = { module = "io.kotest:kotest-assertions-core", version.ref = "kotest" }
+xemantic-kotlin-test = { module="com.xemantic.kotlin:xemantic-kotlin-test", version.ref="xemanticKotlinTest" }
+
 kotest-assertions-json = { module = "io.kotest:kotest-assertions-json", version.ref = "kotest" }
 bignum = { module = "com.ionspin.kotlin:bignum", version.ref = "bignum" }
 
diff --git a/src/commonTest/kotlin/JsonSchemaTest.kt b/src/commonTest/kotlin/JsonSchemaTest.kt
index 41a8415..6ef2d25 100644
--- a/src/commonTest/kotlin/JsonSchemaTest.kt
+++ b/src/commonTest/kotlin/JsonSchemaTest.kt
@@ -17,8 +17,10 @@
 package com.xemantic.ai.tool.schema
 
 import io.kotest.assertions.json.shouldEqualJson
-import io.kotest.assertions.throwables.shouldThrowWithMessage
+import com.xemantic.kotlin.test.should
+import com.xemantic.kotlin.test.have
 import kotlin.test.Test
+import kotlin.test.assertFailsWith
 
 class JsonSchemaTest {
 
@@ -33,7 +35,7 @@ class JsonSchemaTest {
       )
       required = listOf("name")
       additionalProperties = false
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "object",
         "title": "Person",
@@ -68,7 +70,7 @@ class JsonSchemaTest {
           )
         }
       )
-    }.toString() shouldEqualJson $$"""
+    }.toString() shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "title": "Person",
@@ -99,7 +101,7 @@ class JsonSchemaTest {
 
   @Test
   fun `should create empty ObjectSchema`() {
-    ObjectSchema {}.toString() shouldEqualJson """{"type": "object"}"""
+    ObjectSchema {}.toString() shouldEqualJson /* language=json */ """{"type": "object"}"""
   }
 
   @Test
@@ -110,7 +112,7 @@ class JsonSchemaTest {
       minLength = 3
       maxLength = 20
       pattern = "^[a-zA-Z0-9_]+$"
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "string",
         "title": "Username",
@@ -130,7 +132,7 @@ class JsonSchemaTest {
       minLength = 3
       maxLength = 100
       format(StringFormat.EMAIL)
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "string",
         "title": "Email",
@@ -147,7 +149,7 @@ class JsonSchemaTest {
     StringSchema {
       title = "Color"
       enum = listOf("red", "green", "blue")
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "string",
         "title": "Color",
@@ -163,20 +165,20 @@ class JsonSchemaTest {
       description = "User's avatar image"
       contentEncoding = ContentEncoding.BASE64
       contentMediaType = "image/png"
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "string",
         "title": "Image",
         "description": "User's avatar image",
         "contentEncoding": "base64",
         "contentMediaType": "image/png"
-      }      
+      }            
     """
   }
 
   @Test
   fun `should create empty StringSchema`() {
-    StringSchema {}.toString() shouldEqualJson """{"type": "string"}"""
+    StringSchema {}.toString() shouldEqualJson /* language=json */ """{"type": "string"}"""
   }
 
   @Test
@@ -188,7 +190,7 @@ class JsonSchemaTest {
       minItems = 1
       maxItems = 10
       uniqueItems = true
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "array",
         "title": "Numbers",
@@ -213,7 +215,7 @@ class JsonSchemaTest {
           "name" to StringSchema {}
         )
       }
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "array",
         "title": "Users",
@@ -240,7 +242,7 @@ class JsonSchemaTest {
       minimum = 0.0
       maximum = 1000.0
       multipleOf = 0.01
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "number",
         "title": "Price",
@@ -259,7 +261,7 @@ class JsonSchemaTest {
       description = "A price value"
       exclusiveMinimum = 0.0
       exclusiveMaximum = 1000.0
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "number",
         "title": "Price",
@@ -272,7 +274,7 @@ class JsonSchemaTest {
 
   @Test
   fun `should create empty NumberSchema`() {
-    NumberSchema {}.toString() shouldEqualJson """{"type": "number"}"""
+    NumberSchema {}.toString() shouldEqualJson /* language=json */ """{"type": "number"}"""
   }
 
   @Test
@@ -283,7 +285,7 @@ class JsonSchemaTest {
       minimum = 0
       maximum = 120
       multipleOf = 1
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "integer",
         "title": "Age",
@@ -302,7 +304,7 @@ class JsonSchemaTest {
       description = "A person's age"
       exclusiveMinimum = 0
       exclusiveMaximum = 120
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "integer",
         "title": "Age",
@@ -315,7 +317,7 @@ class JsonSchemaTest {
 
   @Test
   fun `should create empty IntegerSchema`() {
-    IntegerSchema {}.toString() shouldEqualJson """{"type": "integer"}"""
+    IntegerSchema {}.toString() shouldEqualJson /* language=json */ """{"type": "integer"}"""
   }
 
   @Test
@@ -323,7 +325,7 @@ class JsonSchemaTest {
     BooleanSchema {
       title = "Is Active"
       description = "Whether the user is active"
-    }.toString() shouldEqualJson """
+    }.toString() shouldEqualJson /* language=json */ """
       {
         "type": "boolean",
         "title": "Is Active",
@@ -334,12 +336,12 @@ class JsonSchemaTest {
 
   @Test
   fun `should create empty BooleanSchema`() {
-    BooleanSchema {}.toString() shouldEqualJson """{"type": "boolean"}"""
+    BooleanSchema {}.toString() shouldEqualJson /* language=json */ """{"type": "boolean"}"""
   }
 
   @Test
   fun `should create JsonSchemaRef`() {
-    JsonSchema.Ref("#/definitions/address").toString() shouldEqualJson $$"""
+    JsonSchema.Ref("#/definitions/address").toString() shouldEqualJson /* language=json */ $$"""
       {
         "$ref": "#/definitions/address"
       }
@@ -348,10 +350,10 @@ class JsonSchemaTest {
 
   @Test
   fun `should throw Exception for invalid JSON Pointer passed to JsonSchemaRef`() {
-    shouldThrowWithMessage<IllegalArgumentException>(
-      "The 'ref' must start with '#/'"
-    ) {
+    assertFailsWith<IllegalArgumentException> {
       JsonSchema.Ref("invalid_ref")
+    } should {
+      have(message == "The 'ref' must start with '#/'")
     }
   }
 
diff --git a/src/commonTest/kotlin/generator/JsonSchemaGeneratorTest.kt b/src/commonTest/kotlin/generator/JsonSchemaGeneratorTest.kt
index f8e83c3..36b8993 100644
--- a/src/commonTest/kotlin/generator/JsonSchemaGeneratorTest.kt
+++ b/src/commonTest/kotlin/generator/JsonSchemaGeneratorTest.kt
@@ -76,7 +76,7 @@ class JsonSchemaGeneratorTest {
   @Test
   fun `generate JSON Schema for Address`() {
     val schema = jsonSchemaOf<Address>()
-    testJson.encodeToString(schema) shouldEqualJson """
+    testJson.encodeToString(schema) shouldEqualJson /* language=json */ """
       {
         "type": "object",
         "title": "The full address",
@@ -181,7 +181,7 @@ class JsonSchemaGeneratorTest {
     val schemaJson = testJson.encodeToString(schema)
 
     // then
-    schemaJson shouldEqualJson $$"""
+    schemaJson shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "description": "Personal data",
@@ -346,7 +346,7 @@ class JsonSchemaGeneratorTest {
   @Test
   fun `should prioritize title and description set on property over the one set for the whole class`() {
     val schema = jsonSchemaOf<Foo>()
-    testJson.encodeToString(schema) shouldEqualJson $$"""
+    testJson.encodeToString(schema) shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "description": "A container of monetary amounts",
@@ -377,7 +377,7 @@ class JsonSchemaGeneratorTest {
     val schema = jsonSchemaOf<Foo>(
       suppressDescription = true
     )
-    testJson.encodeToString(schema) shouldEqualJson $$"""
+    testJson.encodeToString(schema) shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "properties": {
@@ -416,7 +416,7 @@ class JsonSchemaGeneratorTest {
     val schema = jsonSchemaOf<Bar>(
       outputAdditionalPropertiesFalse = true
     )
-    testJson.encodeToString(schema) shouldEqualJson $$"""
+    testJson.encodeToString(schema) shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "properties": {
diff --git a/src/commonTest/kotlin/serialization/JsonSchemaSerializerTest.kt b/src/commonTest/kotlin/serialization/JsonSchemaSerializerTest.kt
index 244a36d..6f9b1e9 100644
--- a/src/commonTest/kotlin/serialization/JsonSchemaSerializerTest.kt
+++ b/src/commonTest/kotlin/serialization/JsonSchemaSerializerTest.kt
@@ -18,27 +18,31 @@ package com.xemantic.ai.tool.schema.serialization
 
 import com.xemantic.ai.tool.schema.JsonSchema
 import com.xemantic.ai.tool.schema.test.testJson
+import com.xemantic.kotlin.test.be
+import com.xemantic.kotlin.test.have
+import com.xemantic.kotlin.test.should
 import io.kotest.assertions.json.shouldEqualJson
-import io.kotest.matchers.shouldBe
-import io.kotest.matchers.types.instanceOf
 import kotlin.test.Test
 
 class JsonSchemaSerializerTest {
 
   @Test
   fun `should decode JsonSchema reference`() {
+    /* language=json */
     val json = $$"""
       {
         "$ref": "#/definitions/foo"
       }
-    """.trimIndent()
-    val ref = testJson.decodeFromString<JsonSchema>(json)
-    ref shouldBe instanceOf<JsonSchema.Ref>()
-    (ref as JsonSchema.Ref).ref shouldBe "#/definitions/foo"
+    """
+    testJson.decodeFromString<JsonSchema>(json) should {
+      be<JsonSchema.Ref>()
+      have(ref == "#/definitions/foo")
+    }
   }
 
   @Test
   fun `decode JSON Schema from JSON`() {
+    /* language=json */
     val json = $$"""
       {
         "type": "object",
@@ -181,7 +185,11 @@ class JsonSchemaSerializerTest {
         }
       }
     """
+
+    // when
     val schema = testJson.decodeFromString<JsonSchema>(json)
+
+    // then
     schema.toString() shouldEqualJson json
   }
 
diff --git a/src/jvmTest/kotlin/serialization/JavaBigDecimalToSchemaTest.kt b/src/jvmTest/kotlin/serialization/JavaBigDecimalToSchemaTest.kt
index d2c14e5..ec903b2 100644
--- a/src/jvmTest/kotlin/serialization/JavaBigDecimalToSchemaTest.kt
+++ b/src/jvmTest/kotlin/serialization/JavaBigDecimalToSchemaTest.kt
@@ -45,7 +45,7 @@ class JavaBigDecimalToSchemaTest {
   @Test
   fun `should represent Java BigDecimal as String with pattern and description JSON Schema`() {
     val schema = jsonSchemaOf<FinancialReport>()
-    testJson.encodeToString(schema) shouldEqualJson $$"""
+    testJson.encodeToString(schema) shouldEqualJson /* language=json */ $$"""
       {
         "type": "object",
         "properties": {