diff --git a/src/Elastic.Apm/Api/CapturedException.cs b/src/Elastic.Apm/Api/CapturedException.cs
index ab7110235..96484f32f 100644
--- a/src/Elastic.Apm/Api/CapturedException.cs
+++ b/src/Elastic.Apm/Api/CapturedException.cs
@@ -3,15 +3,15 @@
 // See the LICENSE file in the project root for more information
 
 using System.Collections.Generic;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api
 {
 	public class CapturedException
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Code { get; set; }
 
 		public bool Handled { get; set; }
@@ -21,7 +21,7 @@ public class CapturedException
 		[JsonProperty("stacktrace")]
 		public List<CapturedStackFrame> StackTrace { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Type { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(CapturedException))
diff --git a/src/Elastic.Apm/Api/Constraints/MaxLengthAttribute.cs b/src/Elastic.Apm/Api/Constraints/MaxLengthAttribute.cs
new file mode 100644
index 000000000..fae0f00c6
--- /dev/null
+++ b/src/Elastic.Apm/Api/Constraints/MaxLengthAttribute.cs
@@ -0,0 +1,34 @@
+// Licensed to Elasticsearch B.V under
+// one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System;
+
+namespace Elastic.Apm.Api.Constraints
+{
+	/// <summary>
+	/// Specifies the maximum length of string data allowed in a property, based on the APM server specification.
+	/// </summary>
+	[AttributeUsage(AttributeTargets.Property)]
+	public sealed class MaxLengthAttribute : Attribute
+	{
+		/// <summary>
+		/// The maximum length.
+		/// </summary>
+		public int Length { get; }
+
+		/// <summary>
+		/// Initializes a new instance of <see cref="MaxLengthAttribute"/>
+		/// with a maximum length of <see cref="Consts.PropertyMaxLength"/>
+		/// </summary>
+		public MaxLengthAttribute() : this(Consts.PropertyMaxLength)
+		{
+		}
+
+		/// <summary>
+		/// Initializes a new instance of <see cref="MaxLengthAttribute"/> with a given maximum length
+		/// </summary>
+		public MaxLengthAttribute(int length) => Length = length;
+	}
+}
diff --git a/src/Elastic.Apm/Api/Constraints/RequiredAttribute.cs b/src/Elastic.Apm/Api/Constraints/RequiredAttribute.cs
new file mode 100644
index 000000000..54f2ddb75
--- /dev/null
+++ b/src/Elastic.Apm/Api/Constraints/RequiredAttribute.cs
@@ -0,0 +1,15 @@
+// Licensed to Elasticsearch B.V under
+// one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System;
+
+namespace Elastic.Apm.Api.Constraints
+{
+	/// <summary>
+	/// Specifies that a data field value is required.
+	/// </summary>
+	[AttributeUsage(AttributeTargets.Property)]
+	public sealed class RequiredAttribute : Attribute { }
+}
diff --git a/src/Elastic.Apm/Report/Serialization/SanitizationAttribute.cs b/src/Elastic.Apm/Api/Constraints/SanitizeAttribute.cs
similarity index 74%
rename from src/Elastic.Apm/Report/Serialization/SanitizationAttribute.cs
rename to src/Elastic.Apm/Api/Constraints/SanitizeAttribute.cs
index fe7c0c1ee..027391797 100644
--- a/src/Elastic.Apm/Report/Serialization/SanitizationAttribute.cs
+++ b/src/Elastic.Apm/Api/Constraints/SanitizeAttribute.cs
@@ -1,14 +1,15 @@
-// Licensed to Elasticsearch B.V under one or more agreements.
-// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
-// See the LICENSE file in the project root for more information
-
-using System;
-
-namespace Elastic.Apm.Report.Serialization
-{
-	/// <summary>
-	/// An attribute to mark fields for sanitization. This attribute is known to <see cref="ElasticApmContractResolver"/> and it applies a Converter
-	/// to sanitize field(s) accordingly.
-	/// </summary>
-	internal class SanitizationAttribute : Attribute { }
-}
+// Licensed to Elasticsearch B.V under one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System;
+using Elastic.Apm.Report.Serialization;
+
+namespace Elastic.Apm.Api.Constraints
+{
+	/// <summary>
+	/// An attribute to mark fields for sanitization. This attribute is known to <see cref="ElasticApmContractResolver"/> and it applies a Converter
+	/// to sanitize field(s) accordingly.
+	/// </summary>
+	internal sealed class SanitizeAttribute : Attribute { }
+}
diff --git a/src/Elastic.Apm/Api/Container.cs b/src/Elastic.Apm/Api/Container.cs
index 3965806eb..0f2b26ac6 100644
--- a/src/Elastic.Apm/Api/Container.cs
+++ b/src/Elastic.Apm/Api/Container.cs
@@ -2,14 +2,14 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
+using Elastic.Apm.Api.Constraints;
 
 namespace Elastic.Apm.Api
 {
 	public class Container
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[Required]
+		[MaxLength]
 		public string Id { get; set; }
 	}
 }
diff --git a/src/Elastic.Apm/Api/Database.cs b/src/Elastic.Apm/Api/Database.cs
index 1e117db29..355e87f94 100644
--- a/src/Elastic.Apm/Api/Database.cs
+++ b/src/Elastic.Apm/Api/Database.cs
@@ -2,8 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
+using Elastic.Apm.Api.Constraints;
 
 namespace Elastic.Apm.Api
 {
@@ -18,7 +17,7 @@ public class Database
 
 		public string Instance { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter), 10_000)]
+		[MaxLength(10_000)]
 		public string Statement { get; set; }
 
 		public string Type { get; set; }
diff --git a/src/Elastic.Apm/Api/Destination.cs b/src/Elastic.Apm/Api/Destination.cs
index dab128346..f0a4bb8a5 100644
--- a/src/Elastic.Apm/Api/Destination.cs
+++ b/src/Elastic.Apm/Api/Destination.cs
@@ -2,8 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
+using Elastic.Apm.Api.Constraints;
 
 namespace Elastic.Apm.Api
 {
@@ -24,7 +23,7 @@ public class Destination
 		/// (for example <see cref="SpanContext.Http" /> or <see cref="SpanContext.Db" />).
 		/// Explicitly setting this property to <c>null</c> will prohibit this automatic deduction.
 		/// </summary>
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Address
 		{
 			get => _address.Value;
@@ -72,20 +71,20 @@ public class DestinationService
 			/// <summary>
 			/// Identifier for the destination service (e.g. 'http://elastic.co', 'elasticsearch', 'rabbitmq')"
 			/// </summary>
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Name { get; set; }
 
 			/// <summary>
 			/// Identifier for the destination service resource being operated on (e.g. 'http://elastic.co:80', 'elasticsearch',
 			/// 'rabbitmq/queue_name')
 			/// </summary>
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Resource { get; set; }
 
 			/// <summary>
 			/// Type of the destination service (e.g. 'db', 'elasticsearch'). Should typically be the same as span.type.
 			/// </summary>
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Type { get; set; }
 		}
 
diff --git a/src/Elastic.Apm/Api/Http.cs b/src/Elastic.Apm/Api/Http.cs
index b83c98171..b239cd44c 100644
--- a/src/Elastic.Apm/Api/Http.cs
+++ b/src/Elastic.Apm/Api/Http.cs
@@ -4,6 +4,7 @@
 
 using System;
 using System.Net.Http;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 
@@ -18,7 +19,7 @@ public class Http
 		private Uri _originalUrl;
 		private string _url;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Method { get; set; }
 
 		/// <summary>
diff --git a/src/Elastic.Apm/Api/IExecutionSegment.cs b/src/Elastic.Apm/Api/IExecutionSegment.cs
index 91186fc72..fb7867e3c 100644
--- a/src/Elastic.Apm/Api/IExecutionSegment.cs
+++ b/src/Elastic.Apm/Api/IExecutionSegment.cs
@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Threading.Tasks;
+using Elastic.Apm.Api.Constraints;
 
 namespace Elastic.Apm.Api
 {
@@ -21,11 +22,13 @@ public interface IExecutionSegment
 		/// is automatically calculated when <see cref="End" /> is called.
 		/// </summary>
 		/// <value>The duration.</value>
+		[Required]
 		double? Duration { get; set; }
 
 		/// <summary>
 		/// The id of the item.
 		/// </summary>
+		[Required]
 		string Id { get; }
 
 		/// <summary>
@@ -65,6 +68,7 @@ public interface IExecutionSegment
 		/// <summary>
 		/// Hex encoded 128 random bits ID of the correlated trace.
 		/// </summary>
+		[Required]
 		string TraceId { get; }
 
 		/// <summary>
diff --git a/src/Elastic.Apm/Api/IMetricSet.cs b/src/Elastic.Apm/Api/IMetricSet.cs
index c2d60b230..c1a35a5a3 100644
--- a/src/Elastic.Apm/Api/IMetricSet.cs
+++ b/src/Elastic.Apm/Api/IMetricSet.cs
@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information
 
 using System.Collections.Generic;
+using Elastic.Apm.Api.Constraints;
 
 namespace Elastic.Apm.Api
 {
@@ -14,6 +15,7 @@ public interface IMetricSet
 		/// <summary>
 		/// List of captured metrics as key - value pairs
 		/// </summary>
+		[Required]
 		IEnumerable<MetricSample> Samples { get; set; }
 
 		// TODO: Rename to Timestamp for consistency?
diff --git a/src/Elastic.Apm/Api/ITransaction.cs b/src/Elastic.Apm/Api/ITransaction.cs
index b7a8a1f37..328c20609 100644
--- a/src/Elastic.Apm/Api/ITransaction.cs
+++ b/src/Elastic.Apm/Api/ITransaction.cs
@@ -3,6 +3,8 @@
 // See the LICENSE file in the project root for more information
 
 using System.Collections.Generic;
+using Elastic.Apm.Api.Constraints;
+using Elastic.Apm.Model;
 
 namespace Elastic.Apm.Api
 {
@@ -35,8 +37,15 @@ public interface ITransaction : IExecutionSegment
 		/// The type of the transaction.
 		/// Example: 'request'
 		/// </summary>
+		[Required]
 		string Type { get; set; }
 
+		/// <summary>
+		/// The total number of correlated spans, including started and dropped
+		/// </summary>
+		[Required]
+		SpanCount SpanCount { get; }
+
 		/// <summary>
 		/// If the transaction does not have a ParentId yet, calling this method generates a new ID, sets it as the ParentId of
 		/// this transaction,
diff --git a/src/Elastic.Apm/Api/Kubernetes/KubernetesMetadata.cs b/src/Elastic.Apm/Api/Kubernetes/KubernetesMetadata.cs
index 62f0f5e33..316fd3d38 100644
--- a/src/Elastic.Apm/Api/Kubernetes/KubernetesMetadata.cs
+++ b/src/Elastic.Apm/Api/Kubernetes/KubernetesMetadata.cs
@@ -2,15 +2,14 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api.Kubernetes
 {
 	public class KubernetesMetadata
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Namespace { get; set; }
 
 		public Node Node { get; set; }
diff --git a/src/Elastic.Apm/Api/Kubernetes/Node.cs b/src/Elastic.Apm/Api/Kubernetes/Node.cs
index 24a9285e6..df1e57af4 100644
--- a/src/Elastic.Apm/Api/Kubernetes/Node.cs
+++ b/src/Elastic.Apm/Api/Kubernetes/Node.cs
@@ -2,15 +2,14 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api.Kubernetes
 {
 	public class Node
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Node)) { { nameof(Name), Name } }.ToString();
diff --git a/src/Elastic.Apm/Api/Kubernetes/Pod.cs b/src/Elastic.Apm/Api/Kubernetes/Pod.cs
index e34b50441..ccca159e7 100644
--- a/src/Elastic.Apm/Api/Kubernetes/Pod.cs
+++ b/src/Elastic.Apm/Api/Kubernetes/Pod.cs
@@ -2,18 +2,17 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api.Kubernetes
 {
 	public class Pod
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Uid { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Pod)) { { nameof(Name), Name }, { nameof(Uid), Uid } }.ToString();
diff --git a/src/Elastic.Apm/Api/Node.cs b/src/Elastic.Apm/Api/Node.cs
index 3ee95b0d4..8774a7efc 100644
--- a/src/Elastic.Apm/Api/Node.cs
+++ b/src/Elastic.Apm/Api/Node.cs
@@ -2,8 +2,8 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api
@@ -11,7 +11,7 @@ namespace Elastic.Apm.Api
 	public class Node
 	{
 		[JsonProperty("configured_name")]
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string ConfiguredName { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Node)) { { nameof(ConfiguredName), ConfiguredName } }.ToString();
diff --git a/src/Elastic.Apm/Api/Request.cs b/src/Elastic.Apm/Api/Request.cs
index 6c942a509..75fb7f8b3 100644
--- a/src/Elastic.Apm/Api/Request.cs
+++ b/src/Elastic.Apm/Api/Request.cs
@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information
 
 using System.Collections.Generic;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
@@ -18,21 +19,23 @@ public class Request
 	{
 		public Request(string method, Url url) => (Method, Url) = (method, url);
 
-		[SanitizationAttribute]
+		[Sanitize]
 		public object Body { get; set; }
 
-		[SanitizationAttribute]
+		[Sanitize]
 		public Dictionary<string, string> Headers { get; set; }
 
 		[JsonProperty("http_version")]
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string HttpVersion { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
+		[Required]
 		public string Method { get; set; }
 
 		public Socket Socket { get; set; }
 
+		[Required]
 		public Url Url { get; set; }
 
 		public override string ToString() =>
@@ -55,25 +58,25 @@ public class Url
 		private string _full;
 		private string _raw;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Full
 		{
 			get => _full;
 			set => _full = Http.Sanitize(value, out var newValue) ? newValue : value;
 		}
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("hostname")]
 		public string HostName { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("pathname")]
 		public string PathName { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Protocol { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Raw
 		{
 			get => _raw;
@@ -84,7 +87,7 @@ public string Raw
 		/// The search describes the query string of the request.
 		/// It is expected to have values delimited by ampersands.
 		/// </summary>
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("search")]
 		public string Search { get; set; }
 
diff --git a/src/Elastic.Apm/Api/Service.cs b/src/Elastic.Apm/Api/Service.cs
index f08d748a3..599497c3b 100644
--- a/src/Elastic.Apm/Api/Service.cs
+++ b/src/Elastic.Apm/Api/Service.cs
@@ -4,11 +4,10 @@
 
 using System;
 using System.Reflection;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Config;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Logging;
-using Elastic.Apm.Report.Serialization;
-using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api
 {
@@ -18,20 +17,20 @@ private Service() { }
 
 		public AgentC Agent { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Environment { get; set; }
 
 		public Framework Framework { get; set; }
 		public Language Language { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
 		public Node Node { get; set; }
 
 		public Runtime Runtime { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Version { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Service))
@@ -77,10 +76,10 @@ internal static Service GetDefaultService(IConfigurationReader configurationRead
 
 		public class AgentC
 		{
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Name { get; set; }
 
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Version { get; set; }
 
 			public override string ToString() =>
@@ -90,10 +89,10 @@ public override string ToString() =>
 
 	public class Framework
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Version { get; set; }
 
 		public override string ToString() =>
@@ -102,7 +101,7 @@ public override string ToString() =>
 
 	public class Language
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Language)) { { nameof(Name), Name } }.ToString();
@@ -118,10 +117,10 @@ public class Runtime
 		internal const string DotNetFullFrameworkName = ".NET Framework";
 		internal const string MonoName = "Mono";
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Version { get; set; }
 
 		public override string ToString() => new ToStringBuilder(nameof(Runtime)) { { nameof(Name), Name }, { nameof(Version), Version } }.ToString();
diff --git a/src/Elastic.Apm/Model/SpanCount.cs b/src/Elastic.Apm/Api/SpanCount.cs
similarity index 52%
rename from src/Elastic.Apm/Model/SpanCount.cs
rename to src/Elastic.Apm/Api/SpanCount.cs
index cffe2fb72..af53b4167 100644
--- a/src/Elastic.Apm/Model/SpanCount.cs
+++ b/src/Elastic.Apm/Api/SpanCount.cs
@@ -3,23 +3,33 @@
 // See the LICENSE file in the project root for more information
 
 using System.Threading;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
 
-namespace Elastic.Apm.Model
+namespace Elastic.Apm.Api
 {
-	internal class SpanCount
+	public class SpanCount
 	{
 		private int _dropped;
 		private int _started;
 		private int _total;
+
+		/// <summary>
+		/// Number of spans that have been dropped by the agent recording the transaction
+		/// </summary>
 		public int Dropped => _dropped;
+
+		/// <summary>
+		/// Number of correlated spans that are recorded
+		/// </summary>
+		[Required]
 		public int Started => _started;
 
-		public void IncrementStarted() => Interlocked.Increment(ref _started);
+		internal void IncrementStarted() => Interlocked.Increment(ref _started);
 
-		public void IncrementDropped() => Interlocked.Increment(ref _dropped);
+		internal void IncrementDropped() => Interlocked.Increment(ref _dropped);
 
-		public int IncrementTotal() => Interlocked.Increment(ref _total);
+		internal int IncrementTotal() => Interlocked.Increment(ref _total);
 
 		public override string ToString() =>
 			new ToStringBuilder(nameof(SpanCount)) { { nameof(Started), Started }, { nameof(Dropped), Dropped } }.ToString();
diff --git a/src/Elastic.Apm/Api/System.cs b/src/Elastic.Apm/Api/System.cs
index 8d17e86d2..0f93e2af3 100644
--- a/src/Elastic.Apm/Api/System.cs
+++ b/src/Elastic.Apm/Api/System.cs
@@ -2,6 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Api.Kubernetes;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Report.Serialization;
@@ -16,12 +17,12 @@ public class System
 
 		public Container Container { get; set; }
 
+		[MaxLength]
 		[JsonProperty("detected_hostname")]
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
 		public string DetectedHostName { get; set; }
 
+		[MaxLength]
 		[JsonProperty("hostname")]
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
 		public string HostName
 		{
 			get => _hostName ??= DetectedHostName;
diff --git a/src/Elastic.Apm/Api/User.cs b/src/Elastic.Apm/Api/User.cs
index 2a3903bbb..8b87d3c1a 100644
--- a/src/Elastic.Apm/Api/User.cs
+++ b/src/Elastic.Apm/Api/User.cs
@@ -2,21 +2,21 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Api
 {
 	public class User
 	{
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Email { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Id { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("username")]
 		public string UserName { get; set; }
 
diff --git a/src/Elastic.Apm/Helpers/StringExtensions.cs b/src/Elastic.Apm/Helpers/StringExtensions.cs
index 18765b7fc..e8f56b191 100644
--- a/src/Elastic.Apm/Helpers/StringExtensions.cs
+++ b/src/Elastic.Apm/Helpers/StringExtensions.cs
@@ -32,5 +32,19 @@ internal static bool ContainsOrdinalIgnoreCase(this string thisObj, string subSt
 			thisObj.IndexOf(subStr, StringComparison.OrdinalIgnoreCase) >= 0;
 
 		internal static string ToLog(this string thisObj) => "`" + thisObj + "'";
+
+		/// <summary>
+		/// Truncates the string to a given length, if longer than the length
+		/// </summary>
+		internal static string Truncate(this string input, int length = Consts.PropertyMaxLength)
+		{
+			input.ThrowIfArgumentNull(nameof(input));
+
+			if (input.Length <= length) return input;
+
+			if (length <= 5) return input.Substring(0, length);
+
+			return $"{input.Substring(0, length - 3)}...";
+		}
 	}
 }
diff --git a/src/Elastic.Apm/Model/Error.cs b/src/Elastic.Apm/Model/Error.cs
index 83e9d8a85..eb1cce509 100644
--- a/src/Elastic.Apm/Model/Error.cs
+++ b/src/Elastic.Apm/Model/Error.cs
@@ -3,9 +3,9 @@
 // See the LICENSE file in the project root for more information
 
 using Elastic.Apm.Api;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Logging;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Model
@@ -53,15 +53,15 @@ private Error(string culprit, CapturedException capturedException, string id, st
 		/// </summary>
 		public Context Context { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Culprit { get; set; }
 
 		public CapturedException Exception { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Id { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("parent_id")]
 		public string ParentId { get; set; }
 
@@ -70,13 +70,13 @@ private Error(string culprit, CapturedException capturedException, string id, st
 		/// </summary>
 		public long Timestamp { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("trace_id")]
 		public string TraceId { get; set; }
 
 		public TransactionData Transaction { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("transaction_id")]
 		public string TransactionId { get; set; }
 
@@ -105,7 +105,7 @@ internal TransactionData(bool isSampled, string type)
 			[JsonProperty("sampled")]
 			public bool IsSampled { get; }
 
-			[JsonConverter(typeof(TrimmedStringJsonConverter))]
+			[MaxLength]
 			public string Type { get; }
 
 			public override string ToString() =>
diff --git a/src/Elastic.Apm/Model/Span.cs b/src/Elastic.Apm/Model/Span.cs
index 31cfe6796..a1d6eaf03 100644
--- a/src/Elastic.Apm/Model/Span.cs
+++ b/src/Elastic.Apm/Model/Span.cs
@@ -7,11 +7,11 @@
 using System.Diagnostics;
 using System.Threading.Tasks;
 using Elastic.Apm.Api;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Config;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Logging;
 using Elastic.Apm.Report;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
 
@@ -104,7 +104,7 @@ public Span(
 
 		private bool _isEnded;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Action { get; set; }
 
 		[JsonIgnore]
@@ -125,7 +125,7 @@ public Span(
 		/// <value>The duration.</value>
 		public double? Duration { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Id { get; set; }
 
 		internal InstrumentationFlag InstrumentationFlag { get; }
@@ -136,7 +136,7 @@ public Span(
 		[JsonIgnore]
 		public Dictionary<string, string> Labels => Context.Labels;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name { get; set; }
 
 		/// <summary>
@@ -155,7 +155,7 @@ public Span(
 			ShouldBeSentToApmServer ? Id : TransactionId,
 			IsSampled);
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("parent_id")]
 		public string ParentId { get; set; }
 
@@ -165,7 +165,7 @@ public Span(
 		[JsonProperty("stacktrace")]
 		public List<CapturedStackFrame> StackTrace { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Subtype { get; set; }
 
 		//public decimal Start { get; set; }
@@ -175,15 +175,15 @@ public Span(
 		/// </summary>
 		public long Timestamp { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("trace_id")]
 		public string TraceId { get; set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("transaction_id")]
 		public string TransactionId => _enclosingTransaction.Id;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Type { get; set; }
 
 		/// <summary>
diff --git a/src/Elastic.Apm/Model/Transaction.cs b/src/Elastic.Apm/Model/Transaction.cs
index eb7d01e12..99c9dcd1c 100644
--- a/src/Elastic.Apm/Model/Transaction.cs
+++ b/src/Elastic.Apm/Model/Transaction.cs
@@ -7,11 +7,11 @@
 using System.Diagnostics;
 using System.Threading.Tasks;
 using Elastic.Apm.Api;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Config;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Logging;
 using Elastic.Apm.Report;
-using Elastic.Apm.Report.Serialization;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
 
@@ -223,7 +223,7 @@ void StartActivity()
 		[JsonIgnore]
 		internal bool HasCustomName { get; private set; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Id { get; }
 
 		[JsonIgnore]
@@ -235,7 +235,7 @@ void StartActivity()
 		[JsonIgnore]
 		public Dictionary<string, string> Labels => Context.Labels;
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Name
 		{
 			get => _name;
@@ -258,7 +258,7 @@ public string Name
 		[JsonIgnore]
 		public DistributedTracingData OutgoingDistributedTracingData => new DistributedTracingData(TraceId, Id, IsSampled, _traceState);
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("parent_id")]
 		public string ParentId { get; set; }
 
@@ -268,7 +268,7 @@ public string Name
 		/// This is typically the HTTP status code, or e.g. "success" for a background task.
 		/// </summary>
 		/// <value>The result.</value>
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Result { get; set; }
 
 		internal Service Service;
@@ -281,11 +281,11 @@ public string Name
 		/// </summary>
 		public long Timestamp { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		[JsonProperty("trace_id")]
 		public string TraceId { get; }
 
-		[JsonConverter(typeof(TrimmedStringJsonConverter))]
+		[MaxLength]
 		public string Type { get; set; }
 
 		public string EnsureParentId()
diff --git a/src/Elastic.Apm/Report/Serialization/ElasticApmContractResolver.cs b/src/Elastic.Apm/Report/Serialization/ElasticApmContractResolver.cs
index 2784dcf1c..9bbb63d50 100644
--- a/src/Elastic.Apm/Report/Serialization/ElasticApmContractResolver.cs
+++ b/src/Elastic.Apm/Report/Serialization/ElasticApmContractResolver.cs
@@ -6,6 +6,7 @@
 using System.Linq;
 using System.Reflection;
 using Elastic.Apm.Api;
+using Elastic.Apm.Api.Constraints;
 using Elastic.Apm.Config;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Serialization;
@@ -16,6 +17,9 @@ internal class ElasticApmContractResolver : DefaultContractResolver
 	{
 		private readonly HeaderDictionarySanitizerConverter _headerDictionarySanitizerConverter;
 
+		private readonly TruncateJsonConverter _defaultTruncateJsonConverter =
+			new TruncateJsonConverter(Consts.PropertyMaxLength);
+
 		public ElasticApmContractResolver(IConfigurationReader configurationReader)
 		{
 			NamingStrategy = new CamelCaseNamingStrategy { ProcessDictionaryKeys = true, OverrideSpecifiedNames = true };
@@ -26,11 +30,22 @@ protected override JsonProperty CreateProperty(MemberInfo member, MemberSerializ
 		{
 			var property = base.CreateProperty(member, memberSerialization);
 
-			if (member.MemberType != MemberTypes.Property || !(member is PropertyInfo propInfo)
-				|| propInfo.CustomAttributes.All(n => n.AttributeType != typeof(SanitizationAttribute))) return property;
-
-			if (propInfo.PropertyType == typeof(Dictionary<string, string>))
-				property.Converter = _headerDictionarySanitizerConverter;
+			if (property.PropertyType == typeof(string))
+			{
+				var maxLengthAttribute = member.GetCustomAttribute<MaxLengthAttribute>();
+				if (maxLengthAttribute != null)
+				{
+					property.Converter = maxLengthAttribute.Length == Consts.PropertyMaxLength
+						? _defaultTruncateJsonConverter
+						: new TruncateJsonConverter(maxLengthAttribute.Length);
+				}
+			}
+			else if (property.PropertyType == typeof(Dictionary<string, string>))
+			{
+				var sanitizeAttribute = member.GetCustomAttribute<SanitizeAttribute>();
+				if (sanitizeAttribute != null)
+					property.Converter = _headerDictionarySanitizerConverter;
+			}
 
 			return property;
 		}
diff --git a/src/Elastic.Apm/Report/Serialization/HeaderDictionarySanitizerConverter.cs b/src/Elastic.Apm/Report/Serialization/HeaderDictionarySanitizerConverter.cs
index ae9f5e292..93517681c 100644
--- a/src/Elastic.Apm/Report/Serialization/HeaderDictionarySanitizerConverter.cs
+++ b/src/Elastic.Apm/Report/Serialization/HeaderDictionarySanitizerConverter.cs
@@ -25,7 +25,7 @@ public override void WriteJson(JsonWriter writer, Dictionary<string, string> hea
 			writer.WriteStartObject();
 			foreach (var keyValue in headers)
 			{
-				writer.WritePropertyName(SerializationUtils.TrimToPropertyMaxLength(keyValue.Key));
+				writer.WritePropertyName(keyValue.Key.Truncate());
 
 				if (keyValue.Value != null)
 				{
diff --git a/src/Elastic.Apm/Report/Serialization/LabelsJsonConverter.cs b/src/Elastic.Apm/Report/Serialization/LabelsJsonConverter.cs
index 9a7099762..3956b13d1 100644
--- a/src/Elastic.Apm/Report/Serialization/LabelsJsonConverter.cs
+++ b/src/Elastic.Apm/Report/Serialization/LabelsJsonConverter.cs
@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using Elastic.Apm.Helpers;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Report.Serialization
@@ -16,13 +17,13 @@ public override void WriteJson(JsonWriter writer, Dictionary<string, string> lab
 			foreach (var keyValue in labels)
 			{
 				// Labels are trimmed and also de dotted in order to satisfy the Intake API
-				writer.WritePropertyName(SerializationUtils.TrimToPropertyMaxLength(keyValue.Key)
+				writer.WritePropertyName(keyValue.Key.Truncate()
 					.Replace('.', '_')
 					.Replace('*', '_')
 					.Replace('"', '_'));
 
 				if (keyValue.Value != null)
-					writer.WriteValue(SerializationUtils.TrimToPropertyMaxLength(keyValue.Value));
+					writer.WriteValue(keyValue.Value.Truncate());
 				else
 					writer.WriteNull();
 			}
diff --git a/src/Elastic.Apm/Report/Serialization/SerializationUtils.cs b/src/Elastic.Apm/Report/Serialization/SerializationUtils.cs
deleted file mode 100644
index b6372cb9b..000000000
--- a/src/Elastic.Apm/Report/Serialization/SerializationUtils.cs
+++ /dev/null
@@ -1,24 +0,0 @@
-// Licensed to Elasticsearch B.V under one or more agreements.
-// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
-// See the LICENSE file in the project root for more information
-
-using Elastic.Apm.Helpers;
-
-namespace Elastic.Apm.Report.Serialization
-{
-	internal static class SerializationUtils
-	{
-		internal static string TrimToLength(string input, int maxLength)
-		{
-			input.ThrowIfArgumentNull(nameof(input));
-
-			if (input.Length <= maxLength) return input;
-
-			if (maxLength <= 5) return input.Substring(0, maxLength);
-
-			return $"{input.Substring(0, maxLength - 3)}...";
-		}
-
-		internal static string TrimToPropertyMaxLength(string input) => TrimToLength(input, Consts.PropertyMaxLength);
-	}
-}
diff --git a/src/Elastic.Apm/Report/Serialization/TrimmedStringJsonConverter.cs b/src/Elastic.Apm/Report/Serialization/TruncateJsonConverter.cs
similarity index 66%
rename from src/Elastic.Apm/Report/Serialization/TrimmedStringJsonConverter.cs
rename to src/Elastic.Apm/Report/Serialization/TruncateJsonConverter.cs
index 58c77d44a..089473eff 100644
--- a/src/Elastic.Apm/Report/Serialization/TrimmedStringJsonConverter.cs
+++ b/src/Elastic.Apm/Report/Serialization/TruncateJsonConverter.cs
@@ -3,22 +3,26 @@
 // See the LICENSE file in the project root for more information
 
 using System;
+using Elastic.Apm.Helpers;
 using Newtonsoft.Json;
 
 namespace Elastic.Apm.Report.Serialization
 {
-	internal class TrimmedStringJsonConverter : JsonConverter<string>
+	/// <summary>
+	/// Truncates a string to a given length
+	/// </summary>
+	internal class TruncateJsonConverter : JsonConverter<string>
 	{
 		private readonly int _maxLength;
 
 		// ReSharper disable once UnusedMember.Global
-		public TrimmedStringJsonConverter() : this(Consts.PropertyMaxLength) { }
+		public TruncateJsonConverter() : this(Consts.PropertyMaxLength) { }
 
 		// ReSharper disable once MemberCanBePrivate.Global
-		public TrimmedStringJsonConverter(int maxLength) => _maxLength = maxLength;
+		public TruncateJsonConverter(int maxLength) => _maxLength = maxLength;
 
 		public override void WriteJson(JsonWriter writer, string value, JsonSerializer serializer) =>
-			writer.WriteValue(SerializationUtils.TrimToLength(value, _maxLength));
+			writer.WriteValue(value.Truncate(_maxLength));
 
 		public override string ReadJson(JsonReader reader, Type objectType, string existingValue, bool hasExistingValue, JsonSerializer serializer) =>
 			reader.Value as string;
diff --git a/test/Elastic.Apm.Tests.MockApmServer/SpanCountDto.cs b/test/Elastic.Apm.Tests.MockApmServer/SpanCountDto.cs
index 92999a064..d04ae325e 100644
--- a/test/Elastic.Apm.Tests.MockApmServer/SpanCountDto.cs
+++ b/test/Elastic.Apm.Tests.MockApmServer/SpanCountDto.cs
@@ -2,6 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using Elastic.Apm.Api;
 using Elastic.Apm.Helpers;
 using Elastic.Apm.Model;
 
diff --git a/test/Elastic.Apm.Tests/SerializationTests.cs b/test/Elastic.Apm.Tests/SerializationTests.cs
index 48c53c30d..f9706fbf1 100644
--- a/test/Elastic.Apm.Tests/SerializationTests.cs
+++ b/test/Elastic.Apm.Tests/SerializationTests.cs
@@ -21,6 +21,11 @@ namespace Elastic.Apm.Tests
 	/// </summary>
 	public class SerializationTests
 	{
+		private readonly PayloadItemSerializer _payloadItemSerializer;
+
+		public SerializationTests() =>
+			_payloadItemSerializer = new PayloadItemSerializer(new MockConfigSnapshot());
+
 		// ReSharper disable once MemberCanBePrivate.Global
 		public static TheoryData SerializationUtilsTrimToPropertyMaxLengthVariantsToTest => new TheoryData<string, string>
 		{
@@ -32,7 +37,7 @@ public class SerializationTests
 		};
 
 		/// <summary>
-		/// Tests the <see cref="TrimmedStringJsonConverter" />. It serializes a transaction with Transaction.Name.Length > 1024.
+		/// Tests the <see cref="TruncateJsonConverter" />. It serializes a transaction with Transaction.Name.Length > 1024.
 		/// Makes sure that the Transaction.Name is truncated correctly.
 		/// </summary>
 		[Fact]
@@ -101,8 +106,8 @@ public void LabelsTruncation()
 			// In Intake API the property is still named `tags'
 			// See https://github.com/elastic/apm-server/blob/6.5/docs/spec/context.json#L43
 			const string intakeApiLabelsPropertyName = "tags";
-			Assert.Equal(Consts.PropertyMaxLength, deserializedContext[intakeApiLabelsPropertyName].Value<JObject>()["foo"]?.Value<string>()?.Length);
-			Assert.Equal("...", deserializedContext[intakeApiLabelsPropertyName].Value<JObject>()["foo"].Value<string>().Substring(1021, 3));
+			Assert.Equal(Consts.PropertyMaxLength, deserializedContext[intakeApiLabelsPropertyName]["foo"].Value<string>().Length);
+			Assert.Equal("...", deserializedContext[intakeApiLabelsPropertyName]["foo"].Value<string>().Substring(1021, 3));
 		}
 
 		/// <summary>
@@ -126,8 +131,8 @@ public void LabelsTruncationSpanContext()
 			// In Intake API the property is still named `tags'
 			// See https://github.com/elastic/apm-server/blob/6.5/docs/spec/spans/common_span.json#L50
 			const string intakeApiLabelsPropertyName = "tags";
-			Assert.Equal(Consts.PropertyMaxLength, deserializedContext[intakeApiLabelsPropertyName].Value<JObject>()["foo"]?.Value<string>()?.Length);
-			Assert.Equal("...", deserializedContext[intakeApiLabelsPropertyName].Value<JObject>()["foo"].Value<string>().Substring(1021, 3));
+			Assert.Equal(Consts.PropertyMaxLength, deserializedContext[intakeApiLabelsPropertyName]["foo"].Value<string>().Length);
+			Assert.Equal("...", deserializedContext[intakeApiLabelsPropertyName]["foo"].Value<string>().Substring(1021, 3));
 		}
 
 		/// <summary>
@@ -177,12 +182,12 @@ public void DictionaryNoTruncateAttributeTest()
 			dummyInstance.DictionaryProp["foo"] = str;
 
 			var json = SerializePayloadItem(dummyInstance);
-			var deserializedDummyInstance = JsonConvert.DeserializeObject(json) as JObject;
+			var deserializedDummyInstance = JsonConvert.DeserializeObject<JObject>(json);
 
 			Assert.NotNull(deserializedDummyInstance);
 
-			Assert.Equal(str.Length, deserializedDummyInstance["dictionaryProp"].Value<JObject>()["foo"]?.Value<string>()?.Length);
-			Assert.Equal(str, deserializedDummyInstance["dictionaryProp"].Value<JObject>()["foo"].Value<string>());
+			Assert.Equal(str.Length, deserializedDummyInstance["dictionaryProp"]["foo"].Value<string>().Length);
+			Assert.Equal(str, deserializedDummyInstance["dictionaryProp"]["foo"].Value<string>());
 		}
 
 		/// <summary>
@@ -259,13 +264,13 @@ public void TransactionContextShouldBeSerializedOnlyWhenSampled()
 			nonSampledTransaction.Context.Request = sampledTransaction.Context.Request;
 
 			var serializedSampledTransaction = SerializePayloadItem(sampledTransaction);
-			var deserializedSampledTransaction = JsonConvert.DeserializeObject(serializedSampledTransaction) as JObject;
+			var deserializedSampledTransaction = JsonConvert.DeserializeObject<JObject>(serializedSampledTransaction);
 			var serializedNonSampledTransaction = SerializePayloadItem(nonSampledTransaction);
-			var deserializedNonSampledTransaction = JsonConvert.DeserializeObject(serializedNonSampledTransaction) as JObject;
+			var deserializedNonSampledTransaction = JsonConvert.DeserializeObject<JObject>(serializedNonSampledTransaction);
 
 			// ReSharper disable once PossibleNullReferenceException
 			deserializedSampledTransaction["sampled"].Value<bool>().Should().BeTrue();
-			deserializedSampledTransaction["context"].Value<JObject>()["request"].Value<JObject>()["url"].Value<JObject>()["full"]
+			deserializedSampledTransaction["context"]["request"]["url"]["full"]
 				.Value<string>()
 				.Should()
 				.Be("https://elastic.co");
@@ -294,15 +299,15 @@ public void TransactionContextShouldBeSerializedOnlyWhenSampled()
 		[InlineData("ABCDEFG", 6, "ABC...")]
 		[InlineData("ABCDEFGH", 6, "ABC...")]
 		[InlineData("ABCDEFGH", 7, "ABCD...")]
-		public void SerializationUtilsTrimToLengthTests(string original, int maxLength, string expectedTrimmed) =>
-			SerializationUtils.TrimToLength(original, maxLength).Should().Be(expectedTrimmed);
+		public void SerializationUtilsTruncateTests(string original, int maxLength, string expectedTrimmed) =>
+			original.Truncate(maxLength).Should().Be(expectedTrimmed);
 
 		[Theory]
 		[MemberData(nameof(SerializationUtilsTrimToPropertyMaxLengthVariantsToTest))]
-		public void SerializationUtilsTrimToPropertyMaxLengthTests(string original, string expectedTrimmed)
+		public void SerializationUtilsTruncateToPropertyMaxLengthTests(string original, string expectedTrimmed)
 		{
 			Consts.PropertyMaxLength.Should().BeGreaterThan(3);
-			SerializationUtils.TrimToPropertyMaxLength(original).Should().Be(expectedTrimmed);
+			original.Truncate().Should().Be(expectedTrimmed);
 		}
 
 		/// <summary>
@@ -343,7 +348,7 @@ public void LabelDeDotting()
 			json = SerializePayloadItem(context);
 			json.Should().Be("{\"tags\":{\"a_b\":\"labelValue1\",\"a_b_c\":\"labelValue2\"}}");
 		}
-    
+
     /// <summary>
 		/// Makes sure that keys in custom are de dotted.
 		/// </summary>
@@ -410,8 +415,8 @@ public void MetricSet_Serializes_And_Deserializes()
 			}
 		}
 
-		private static string SerializePayloadItem(object item) =>
-			new PayloadItemSerializer(new MockConfigSnapshot()).SerializeObject(item);
+		private string SerializePayloadItem(object item) =>
+			_payloadItemSerializer.SerializeObject(item);
 
 		/// <summary>
 		/// A dummy type for tests.