diff --git a/test/Horde/Url/HordeUrlParamRawModeTest.php b/test/Horde/Url/HordeUrlParamRawModeTest.php
new file mode 100644
index 0000000..e74891e
--- /dev/null
+++ b/test/Horde/Url/HordeUrlParamRawModeTest.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * @author     Torben Dannhauer / GPT-5
+ * @license    http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @category   Horde
+ * @package    Url
+ * @subpackage UnitTests
+ */
+
+namespace Horde\Url;
+use \PHPUnit\Framework\TestCase;
+use \Horde_Url;
+
+class HordeUrlParamRawModeTest extends TestCase
+{
+	public function testHordeUrlParamEscapedAndRaw()
+	{
+		$url = new Horde_Url('test');
+		$url->add('url', new Horde_Url('https://example.com/test?_t=123456&_h=Abcd123'));
+		$this->assertEquals(
+			'test?url=https%3A%2F%2Fexample.com%2Ftest%3F_t%3D123456%26_h%3DAbcd123',
+			(string)$url
+		);
+
+		// Raw output should not HTML-escape the ampersands
+		$url->setRaw(true);
+		$this->assertEquals(
+			'test?url=https%3A%2F%2Fexample.com%2Ftest%3F_t%3D123456%26_h%3DAbcd123',
+			(string)$url
+		);
+	}
+}
+
+
diff --git a/test/Horde/Url/NestedParamHordeUrlTest.php b/test/Horde/Url/NestedParamHordeUrlTest.php
new file mode 100644
index 0000000..da8e300
--- /dev/null
+++ b/test/Horde/Url/NestedParamHordeUrlTest.php
@@ -0,0 +1,30 @@
+<?php
+/**
+ * @author     Torben Dannhauer / GPT-5
+ * @license    http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @category   Horde
+ * @package    Url
+ * @subpackage UnitTests
+ */
+
+namespace Horde\Url;
+use \PHPUnit\Framework\TestCase;
+use \Horde_Url;
+
+class NestedParamHordeUrlTest extends TestCase
+{
+	public function testNestedArrayWithHordeUrlIsCurrentlyNotConvertedRecursively()
+	{
+		$url = new Horde_Url('test');
+		$url->add('outer', [
+			'inner' => new Horde_Url('https://example.com/test?_t=1&_h=2')
+		]);
+		// Current behavior: Only top-level values are normalized by PR #2.
+		// Nested arrays containing Horde_Url will still be expanded by http_build_query.
+		// This test documents current behavior and should be adapted once recursion is implemented.
+		$this->assertStringContainsString('outer%5Binner%5D%5Bparameters%5D', (string)$url);
+		$this->markTestIncomplete('Recursive normalization of nested Horde_Url parameters is not implemented yet.');
+	}
+}
+
+
diff --git a/test/Horde/Url/StringableParamTest.php b/test/Horde/Url/StringableParamTest.php
new file mode 100644
index 0000000..8d83887
--- /dev/null
+++ b/test/Horde/Url/StringableParamTest.php
@@ -0,0 +1,33 @@
+<?php
+/**
+ * @author     Torben Dannhauer / GPT-5
+ * @license    http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @category   Horde
+ * @package    Url
+ * @subpackage UnitTests
+ */
+
+namespace Horde\Url;
+use \PHPUnit\Framework\TestCase;
+use \Horde_Url;
+
+class StringableParamTest extends TestCase
+{
+	private function getStringableObject($value)
+	{
+		return new class($value) {
+			private $value;
+			public function __construct($value) { $this->value = $value; }
+			public function __toString() { return (string)$this->value; }
+		};
+	}
+
+	public function testStringableObjectAsParamValue()
+	{
+		$this->markTestIncomplete('Generalized normalization for all stringable objects may be implemented later.');
+		$url = new Horde_Url('test');
+		$url->add('s', $this->getStringableObject('a&b'));
+		// Current implementation only normalizes Horde_Url instances; generic stringables are not cast explicitly.
+		// Keep test incomplete until generalized handling is agreed upon.
+	}
+}