diff --git a/test/UnitTests/Microsoft.Testing.Platform.UnitTests/CommandLine/CommandLineParseResultTests.cs b/test/UnitTests/Microsoft.Testing.Platform.UnitTests/CommandLine/CommandLineParseResultTests.cs
new file mode 100644
index 0000000000..a13fef7c7c
--- /dev/null
+++ b/test/UnitTests/Microsoft.Testing.Platform.UnitTests/CommandLine/CommandLineParseResultTests.cs
@@ -0,0 +1,230 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using Microsoft.Testing.Platform.CommandLine;
+
+namespace Microsoft.Testing.Platform.UnitTests;
+
+[TestClass]
+public sealed class CommandLineParseResultTests
+{
+    [TestMethod]
+    public void Empty_HasNoTool_NoOptions_NoErrors()
+    {
+        CommandLineParseResult empty = CommandLineParseResult.Empty;
+
+        Assert.IsNull(empty.ToolName);
+        Assert.IsFalse(empty.HasTool);
+        Assert.IsFalse(empty.HasError);
+        Assert.IsEmpty(empty.Options);
+        Assert.IsEmpty(empty.Errors);
+    }
+
+    [TestMethod]
+    public void HasTool_TrueWhenToolNameProvided()
+    {
+        var result = new CommandLineParseResult("mytool", [], []);
+
+        Assert.IsTrue(result.HasTool);
+        Assert.AreEqual("mytool", result.ToolName);
+    }
+
+    [TestMethod]
+    public void HasTool_FalseWhenToolNameIsNull()
+    {
+        var result = new CommandLineParseResult(null, [], []);
+
+        Assert.IsFalse(result.HasTool);
+    }
+
+    [TestMethod]
+    public void HasError_TrueWhenErrorsPresent()
+    {
+        var result = new CommandLineParseResult(null, [], ["some error"]);
+
+        Assert.IsTrue(result.HasError);
+    }
+
+    [TestMethod]
+    public void HasError_FalseWhenNoErrors()
+    {
+        var result = new CommandLineParseResult(null, [], []);
+
+        Assert.IsFalse(result.HasError);
+    }
+
+    [TestMethod]
+    public void IsOptionSet_ReturnsTrueForKnownOption()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("verbose", [])], []);
+
+        Assert.IsTrue(result.IsOptionSet("verbose"));
+    }
+
+    [TestMethod]
+    public void IsOptionSet_IsCaseInsensitive()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("verbose", [])], []);
+
+        Assert.IsTrue(result.IsOptionSet("VERBOSE"));
+        Assert.IsTrue(result.IsOptionSet("Verbose"));
+    }
+
+    [TestMethod]
+    public void IsOptionSet_StripsLeadingDashes()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("verbose", [])], []);
+
+        Assert.IsTrue(result.IsOptionSet("--verbose"));
+        Assert.IsTrue(result.IsOptionSet("-verbose"));
+    }
+
+    [TestMethod]
+    public void IsOptionSet_ReturnsFalseForUnknownOption()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("verbose", [])], []);
+
+        Assert.IsFalse(result.IsOptionSet("quiet"));
+    }
+
+    [TestMethod]
+    public void TryGetOptionArgumentList_ReturnsTrueAndArgumentsForKnownOption()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("output", ["file.txt"])], []);
+
+        bool found = result.TryGetOptionArgumentList("output", out string[]? args);
+
+        Assert.IsTrue(found);
+        Assert.IsNotNull(args);
+        Assert.HasCount(1, args);
+        Assert.AreEqual("file.txt", args[0]);
+    }
+
+    [TestMethod]
+    public void TryGetOptionArgumentList_ReturnsFalseForUnknownOption()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("output", ["file.txt"])], []);
+
+        bool found = result.TryGetOptionArgumentList("missing", out string[]? args);
+
+        Assert.IsFalse(found);
+        Assert.IsNull(args);
+    }
+
+    [TestMethod]
+    public void TryGetOptionArgumentList_IsCaseSensitive()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("output", ["file.txt"])], []);
+
+        bool found = result.TryGetOptionArgumentList("OUTPUT", out string[]? args);
+
+        Assert.IsFalse(found);
+        Assert.IsNull(args);
+    }
+
+    [TestMethod]
+    public void TryGetOptionArgumentList_StripsLeadingDashes()
+    {
+        var result = new CommandLineParseResult(null, [new CommandLineParseOption("output", ["file.txt"])], []);
+
+        bool found = result.TryGetOptionArgumentList("--output", out string[]? args);
+
+        Assert.IsTrue(found);
+        Assert.IsNotNull(args);
+        Assert.HasCount(1, args);
+        Assert.AreEqual("file.txt", args[0]);
+    }
+
+    [TestMethod]
+    public void TryGetOptionArgumentList_CombinesArgumentsFromMultipleOccurrences()
+    {
+        var result = new CommandLineParseResult(
+            null,
+            [
+                new CommandLineParseOption("filter", ["Class1"]),
+                new CommandLineParseOption("filter", ["Class2"]),
+            ],
+            []);
+
+        bool found = result.TryGetOptionArgumentList("filter", out string[]? args);
+
+        Assert.IsTrue(found);
+        Assert.IsNotNull(args);
+        Assert.HasCount(2, args);
+        Assert.Contains("Class1", args);
+        Assert.Contains("Class2", args);
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsTrueForIdenticalResults()
+    {
+        var a = new CommandLineParseResult("tool", [new CommandLineParseOption("opt", ["val"])], ["err"]);
+        var b = new CommandLineParseResult("tool", [new CommandLineParseOption("opt", ["val"])], ["err"]);
+
+        Assert.AreEqual(a, b);
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsFalseWhenToolNameDiffers()
+    {
+        var a = new CommandLineParseResult("tool1", [], []);
+        var b = new CommandLineParseResult("tool2", [], []);
+
+        Assert.AreNotEqual(a, b);
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsFalseWhenErrorsDiffer()
+    {
+        var a = new CommandLineParseResult(null, [], ["error1"]);
+        var b = new CommandLineParseResult(null, [], ["error2"]);
+
+        Assert.AreNotEqual(a, b);
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsFalseWhenOptionsDiffer()
+    {
+        var a = new CommandLineParseResult(null, [new CommandLineParseOption("opt1", [])], []);
+        var b = new CommandLineParseResult(null, [new CommandLineParseOption("opt2", [])], []);
+
+        Assert.AreNotEqual(a, b);
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsFalseForNull()
+    {
+        var a = new CommandLineParseResult(null, [], []);
+
+        Assert.IsFalse(a.Equals(null));
+    }
+
+    [TestMethod]
+    public void Equals_ReturnsTrueForSameReference()
+    {
+        var a = new CommandLineParseResult("tool", [], []);
+
+        Assert.AreEqual(a, a);
+    }
+
+    [TestMethod]
+    public void ToString_ContainsToolNameAndOptions()
+    {
+        var result = new CommandLineParseResult("mytool", [new CommandLineParseOption("opt", ["val"])], ["an error"]);
+
+        string text = result.ToString();
+
+        Assert.IsTrue(text.Contains("mytool", StringComparison.Ordinal));
+        Assert.IsTrue(text.Contains("opt", StringComparison.Ordinal));
+        Assert.IsTrue(text.Contains("an error", StringComparison.Ordinal));
+    }
+
+    [TestMethod]
+    public void ToString_EmptyResult_ContainsNone()
+    {
+        string text = CommandLineParseResult.Empty.ToString();
+
+        Assert.IsTrue(text.Contains($"Errors:{Environment.NewLine}    None", StringComparison.Ordinal));
+        Assert.IsTrue(text.Contains($"Options:{Environment.NewLine}    None", StringComparison.Ordinal));
+    }
+}