diff --git a/packages/kilo-jetbrains/AGENTS.md b/packages/kilo-jetbrains/AGENTS.md
index d9a13a7427e..3bb2c6abab0 100644
--- a/packages/kilo-jetbrains/AGENTS.md
+++ b/packages/kilo-jetbrains/AGENTS.md
@@ -268,6 +268,22 @@ Tests for retained Swing components should assert:
 - `update(model)` changes existing labels/body text without duplicating components.
 - Updates while collapsed do not eagerly create lazy bodies.
 - No-op updates, empty deltas, repeated hover values, and toggling non-expandable cards do not repaint/revalidate the whole view.
+- Streaming/rebuilding surfaces additionally require stress + leak tests (see below).
+
+### Stress and Leak Tests for Streaming UI
+
+Session/transcript UI that streams updates or rebuilds its component tree (markdown
+views, code blocks, transcript parts, collapsible cards) must ship stress + leak tests in
+addition to behavior tests. These tests must:
+
+- Drive many updates (hundreds of streamed deltas or `set` cycles) through the public API.
+- Assert that retained component instances stay identical across updates (`assertSame`).
+- Assert the component count stays bounded — no growth per update.
+- Assert disposable-backed resources return to baseline after churn + clear/dispose.
+  For code editors, compare `EditorFactory.getInstance().allEditors.size` against a
+  baseline captured before the loop.
+
+See `MdViewHybridStressTest` for the reference pattern.
 
 ### Platform Components and Utilities
 
diff --git a/packages/kilo-jetbrains/frontend/src/test/kotlin/ai/kilocode/client/ui/md/MdViewHybridStressTest.kt b/packages/kilo-jetbrains/frontend/src/test/kotlin/ai/kilocode/client/ui/md/MdViewHybridStressTest.kt
new file mode 100644
index 00000000000..e9d40248cf6
--- /dev/null
+++ b/packages/kilo-jetbrains/frontend/src/test/kotlin/ai/kilocode/client/ui/md/MdViewHybridStressTest.kt
@@ -0,0 +1,180 @@
+package ai.kilocode.client.ui.md
+
+import ai.kilocode.client.session.ui.style.SessionEditorStyle
+import com.intellij.openapi.editor.EditorFactory
+import com.intellij.openapi.util.Disposer
+import com.intellij.testFramework.fixtures.BasePlatformTestCase
+import com.intellij.ui.EditorTextField
+import com.intellij.ui.components.JBHtmlPane
+import com.intellij.ui.components.JBScrollPane
+import com.intellij.util.ui.UIUtil
+import javax.swing.Box
+import javax.swing.JPanel
+
+/**
+ * Stress + leak coverage for the hybrid markdown renderer.
+ *
+ * These tests drive many updates through the public [MdView] API and inspect the real
+ * Swing component tree to prove that:
+ *  - retained component instances survive heavy streaming,
+ *  - the component tree stays bounded (no per-update growth),
+ *  - editors created for code blocks are released (no leak) after churn + clear.
+ */
+@Suppress("UnstableApiUsage")
+class MdViewHybridStressTest : BasePlatformTestCase() {
+    private lateinit var view: MdView
+    private var disposed = false
+
+    override fun setUp() {
+        super.setUp()
+        view = MdViewFactory.hybrid()
+        disposed = false
+    }
+
+    override fun tearDown() {
+        try {
+            if (this::view.isInitialized && !disposed) Disposer.dispose(view)
+        } finally {
+            super.tearDown()
+        }
+    }
+
+    fun `test streaming a large mixed document token by token stays consistent`() {
+        val doc = buildString {
+            append("# Heading\n\n")
+            append("Intro paragraph with **bold** text.\n\n")
+            append("- one\n- two\n- three\n\n")
+            append("```kotlin\nval x = 1\n```\n\n")
+            append("middle prose paragraph\n\n")
+            append("```java\nclass A {}\n```\n\n")
+            append("closing prose")
+        }
+
+        for (token in doc.chunked(3)) view.append(token)
+
+        assertEquals(doc, view.markdown())
+        assertEquals(3, htmls().size)
+        assertEquals(2, scrolls().size)
+        assertEquals(4, struts().size) // blocks - 1
+        assertEquals(9, panel().componentCount) // 5 blocks + 4 struts = 2*5 - 1
+
+        val html = view.html()
+        assertTrue(html.contains("<h1>"))
+        assertTrue(html.contains("<ul>"))
+        assertTrue(html.contains("class A"))
+        assertFalse(html.contains("<hr"))
+    }
+
+    fun `test trailing appends retain prefix html and code instances`() {
+        view.set("intro\n\n```kotlin\nval x = 1\n```\n\ntail")
+        val intro = htmls().first()
+        val tail = htmls().last()
+        val editor = editors().single()
+        editor.getEditor(true)
+
+        repeat(100) { i -> view.append(" more$i") }
+
+        assertSame(intro, htmls().first())
+        assertSame(tail, htmls().last())
+        assertSame(editor, editors().single())
+        assertEquals(2, htmls().size)
+        assertEquals(1, scrolls().size)
+        assertFalse(editor.getEditor(true)!!.isDisposed)
+        assertTrue(view.markdown().contains("more99"))
+    }
+
+    fun `test repeated same structure set reuses single editor and stays bounded`() {
+        repeat(150) { i ->
+            view.set("```kotlin\nval x = $i\n```")
+            editors().single().getEditor(true)
+        }
+        val editor = editors().single()
+
+        repeat(50) { i -> view.set("```kotlin\nval y = $i\n```") }
+
+        assertSame(editor, editors().single())
+        assertEquals(1, scrolls().size)
+        assertEquals(1, panel().componentCount)
+        assertEquals("val y = 49", editor.text)
+    }
+
+    fun `test structural churn releases every editor after clear`() {
+        val base = EditorFactory.getInstance().allEditors.size
+
+        repeat(60) { i ->
+            view.set("```kotlin\nval x = $i\n```")
+            editors().single().getEditor(true)
+            view.set("```java\nclass A$i {}\n```")
+            editors().single().getEditor(true)
+            view.set("plain prose $i")
+        }
+
+        view.clear()
+        drainEdt()
+
+        assertTrue(scrolls().isEmpty())
+        assertTrue(htmls().isEmpty())
+        assertEquals(0, panel().componentCount)
+        assertEquals(base, EditorFactory.getInstance().allEditors.size)
+    }
+
+    fun `test streaming code body reuses one editor and keeps html in sync`() {
+        view.append("```java\n")
+        val pane = scrolls().single()
+        val editor = editors().single()
+
+        val body = StringBuilder()
+        repeat(100) { i ->
+            val line = "void m$i() {}\n"
+            body.append(line)
+            view.append(line)
+        }
+
+        assertSame(pane, scrolls().single())
+        assertSame(editor, editors().single())
+        assertEquals(body.toString().trimEnd('\n'), editor.text)
+        assertTrue(view.html().contains("void m0()"))
+        assertTrue(view.html().contains("void m99()"))
+
+        view.append("```")
+
+        assertSame(pane, scrolls().single())
+        assertSame(editor, editors().single())
+    }
+
+    fun `test style changes during streaming do not rebuild components`() {
+        view.append("intro\n\n```kotlin\nval x = 1\n```\n\n")
+        val intro = htmls().first()
+        val editor = editors().single()
+        editor.getEditor(true)
+        val styled = SessionEditorStyle.create(family = "Courier New", size = 18)
+        val current = SessionEditorStyle.current()
+
+        repeat(50) { i ->
+            view.append("line $i ")
+            view.applyStyle(if (i % 2 == 0) styled else current)
+            if (i % 5 == 0) view.resetStyles()
+        }
+
+        assertSame(intro, htmls().first())
+        assertSame(editor, editors().single())
+        assertFalse(editor.getEditor(true)!!.isDisposed)
+        assertEquals(2, htmls().size)
+        assertEquals(1, scrolls().size)
+        assertTrue(view.markdown().contains("line 49"))
+    }
+
+    private fun panel(): JPanel = view.component as JPanel
+
+    private fun scrolls(): List<JBScrollPane> = panel().components.filterIsInstance<JBScrollPane>()
+
+    private fun htmls(): List<JBHtmlPane> = panel().components.filterIsInstance<JBHtmlPane>()
+
+    private fun struts(): List<Box.Filler> = panel().components.filterIsInstance<Box.Filler>()
+
+    private fun editors(): List<EditorTextField> = scrolls().mapNotNull { it.viewport.view as? EditorTextField }
+
+    private fun drainEdt() {
+        UIUtil.dispatchAllInvocationEvents()
+    }
+}