diff --git a/app/src/androidTest/java/com/m57/hermescontrol/data/ws/StreamingEventDeviceTest.kt b/app/src/androidTest/java/com/m57/hermescontrol/data/ws/StreamingEventDeviceTest.kt
new file mode 100644
index 00000000..b16f20cc
--- /dev/null
+++ b/app/src/androidTest/java/com/m57/hermescontrol/data/ws/StreamingEventDeviceTest.kt
@@ -0,0 +1,76 @@
+package com.m57.hermescontrol.data.ws
+
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.m57.hermescontrol.theme.HermesControlTheme
+import com.m57.hermescontrol.ui.chat.components.ReasoningCard
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+import org.junit.Assert.assertEquals
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+/** Issue #1163: execute the wire parser on ART, without backend credentials or model calls. */
+@RunWith(AndroidJUnit4::class)
+class StreamingEventDeviceTest {
+    @get:Rule
+    val compose = createComposeRule()
+
+    @Test
+    fun streamingBurstPreservesEveryChunkAndSessionOnDevice() {
+        val types = listOf("message.token", "message.delta", "thinking.delta", "reasoning.delta")
+        for (type in types) {
+            val actual = StringBuilder()
+            val expected = StringBuilder()
+            repeat(1000) { seq ->
+                val frame =
+                    """{"method":"event","params":{"type":"$type","seq":$seq,""" +
+                        """"payload":{"session_id":"device-test","text":"chunk-$seq 🌙\n"}}}"""
+                val response = Json.decodeFromString<JsonRpcResponse>(frame)
+                val event = EventParser.parse(response, frame)
+                val (token, session) =
+                    when (event) {
+                        is WsEvent.MessageToken -> event.token to event.sessionId
+                        is WsEvent.ThinkingDelta -> event.token to event.sessionId
+                        is WsEvent.ReasoningDelta -> event.token to event.sessionId
+                        else -> error("Unexpected streaming event: $event")
+                    }
+                assertEquals("device-test", session)
+                actual.append(token)
+                expected.append("chunk-$seq 🌙\n")
+            }
+            assertEquals(type, expected.toString(), actual.toString())
+        }
+    }
+
+    @Test
+    fun reasoningFastPathAvoidsContainerTraversalAndRendersOnDevice() {
+        val fields =
+            mapOf<String, JsonElement>(
+                "type" to JsonPrimitive("reasoning.delta"),
+                "payload" to JsonObject(mapOf("text" to JsonPrimitive("Device streaming verified"))),
+            )
+        val params =
+            JsonObject(
+                object : Map<String, JsonElement> by fields {
+                    override val entries: Set<Map.Entry<String, JsonElement>>
+                        get() = error("Streaming parser traversed the params tree")
+                },
+            )
+        val event = EventParser.parse(JsonRpcResponse(method = "event", params = params)) as WsEvent.ReasoningDelta
+        compose.setContent {
+            HermesControlTheme {
+                ReasoningCard(reasoningText = event.token)
+            }
+        }
+        compose.onNodeWithTag("reasoning_card").performClick()
+        compose.onNodeWithText("Device streaming verified").assertIsDisplayed()
+    }
+}