diff --git a/gateway/platforms/base.py b/gateway/platforms/base.py
index 0a8390a7a..e57a84bb3 100644
--- a/gateway/platforms/base.py
+++ b/gateway/platforms/base.py
@@ -502,6 +502,14 @@ class MessageType(Enum):
     COMMAND = "command"  # /command style
 
 
+class ProcessingOutcome(Enum):
+    """Result classification for message-processing lifecycle hooks."""
+
+    SUCCESS = "success"
+    FAILURE = "failure"
+    CANCELLED = "cancelled"
+
+
 @dataclass
 class MessageEvent:
     """
@@ -625,6 +633,7 @@ class BasePlatformAdapter(ABC):
         # Gateway shutdown cancels these so an old gateway instance doesn't keep
         # working on a task after --replace or manual restarts.
         self._background_tasks: set[asyncio.Task] = set()
+        self._expected_cancelled_tasks: set[asyncio.Task] = set()
         # Chats where auto-TTS on voice input is disabled (set by /voice off)
         self._auto_tts_disabled_chats: set = set()
         # Chats where typing indicator is paused (e.g. during approval waits).
@@ -1133,7 +1142,7 @@ class BasePlatformAdapter(ABC):
     async def on_processing_start(self, event: MessageEvent) -> None:
         """Hook called when background processing begins."""
 
-    async def on_processing_complete(self, event: MessageEvent, success: bool) -> None:
+    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
         """Hook called when background processing completes."""
 
     async def _run_processing_hook(self, hook_name: str, *args: Any, **kwargs: Any) -> None:
@@ -1352,6 +1361,7 @@ class BasePlatformAdapter(ABC):
             return
         if hasattr(task, "add_done_callback"):
             task.add_done_callback(self._background_tasks.discard)
+            task.add_done_callback(self._expected_cancelled_tasks.discard)
     
     @staticmethod
     def _get_human_delay() -> float:
@@ -1580,7 +1590,11 @@ class BasePlatformAdapter(ABC):
 
             # Determine overall success for the processing hook
             processing_ok = delivery_succeeded if delivery_attempted else not bool(response)
-            await self._run_processing_hook("on_processing_complete", event, processing_ok)
+            await self._run_processing_hook(
+                "on_processing_complete",
+                event,
+                ProcessingOutcome.SUCCESS if processing_ok else ProcessingOutcome.FAILURE,
+            )
 
             # Check if there's a pending message that was queued during our processing
             if session_key in self._pending_messages:
@@ -1599,10 +1613,14 @@ class BasePlatformAdapter(ABC):
                 return  # Already cleaned up
                 
         except asyncio.CancelledError:
-            await self._run_processing_hook("on_processing_complete", event, False)
+            current_task = asyncio.current_task()
+            outcome = ProcessingOutcome.CANCELLED
+            if current_task is None or current_task not in self._expected_cancelled_tasks:
+                outcome = ProcessingOutcome.FAILURE
+            await self._run_processing_hook("on_processing_complete", event, outcome)
             raise
         except Exception as e:
-            await self._run_processing_hook("on_processing_complete", event, False)
+            await self._run_processing_hook("on_processing_complete", event, ProcessingOutcome.FAILURE)
             logger.error("[%s] Error handling message: %s", self.name, e, exc_info=True)
             # Send the error to the user so they aren't left with radio silence
             try:
@@ -1646,10 +1664,12 @@ class BasePlatformAdapter(ABC):
         """
         tasks = [task for task in self._background_tasks if not task.done()]
         for task in tasks:
+            self._expected_cancelled_tasks.add(task)
             task.cancel()
         if tasks:
             await asyncio.gather(*tasks, return_exceptions=True)
         self._background_tasks.clear()
+        self._expected_cancelled_tasks.clear()
         self._pending_messages.clear()
         self._active_sessions.clear()
 
diff --git a/gateway/platforms/discord.py b/gateway/platforms/discord.py
index 34a51e721..e503f0edd 100644
--- a/gateway/platforms/discord.py
+++ b/gateway/platforms/discord.py
@@ -49,6 +49,7 @@ from gateway.platforms.base import (
     BasePlatformAdapter,
     MessageEvent,
     MessageType,
+    ProcessingOutcome,
     SendResult,
     cache_image_from_url,
     cache_audio_from_url,
@@ -754,14 +755,17 @@ class DiscordAdapter(BasePlatformAdapter):
         if hasattr(message, "add_reaction"):
             await self._add_reaction(message, "👀")
 
-    async def on_processing_complete(self, event: MessageEvent, success: bool) -> None:
+    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
         """Swap the in-progress reaction for a final success/failure reaction."""
         if not self._reactions_enabled():
             return
         message = event.raw_message
         if hasattr(message, "add_reaction"):
             await self._remove_reaction(message, "👀")
-            await self._add_reaction(message, "✅" if success else "❌")
+            if outcome == ProcessingOutcome.SUCCESS:
+                await self._add_reaction(message, "✅")
+            elif outcome == ProcessingOutcome.FAILURE:
+                await self._add_reaction(message, "❌")
 
     async def send(
         self,
diff --git a/gateway/platforms/matrix.py b/gateway/platforms/matrix.py
index 750df7a29..cf72d9566 100644
--- a/gateway/platforms/matrix.py
+++ b/gateway/platforms/matrix.py
@@ -40,6 +40,7 @@ from gateway.platforms.base import (
     BasePlatformAdapter,
     MessageEvent,
     MessageType,
+    ProcessingOutcome,
     SendResult,
 )
 
@@ -1479,7 +1480,7 @@ class MatrixAdapter(BasePlatformAdapter):
             await self._send_reaction(room_id, msg_id, "\U0001f440")
 
     async def on_processing_complete(
-        self, event: MessageEvent, success: bool,
+        self, event: MessageEvent, outcome: ProcessingOutcome,
     ) -> None:
         """Replace eyes with checkmark (success) or cross (failure)."""
         if not self._reactions_enabled:
@@ -1488,11 +1489,15 @@ class MatrixAdapter(BasePlatformAdapter):
         room_id = event.source.chat_id
         if not msg_id or not room_id:
             return
+        if outcome == ProcessingOutcome.CANCELLED:
+            return
         # Note: Matrix doesn't support removing a specific reaction easily
         # without tracking the reaction event_id. We send the new reaction;
         # the eyes stays (acceptable UX — both are visible).
         await self._send_reaction(
-            room_id, msg_id, "\u2705" if success else "\u274c",
+            room_id,
+            msg_id,
+            "\u2705" if outcome == ProcessingOutcome.SUCCESS else "\u274c",
         )
 
     async def _on_reaction(self, room: Any, event: Any) -> None:
diff --git a/gateway/platforms/telegram.py b/gateway/platforms/telegram.py
index 91de45fe8..ac5b7fb8c 100644
--- a/gateway/platforms/telegram.py
+++ b/gateway/platforms/telegram.py
@@ -60,6 +60,7 @@ from gateway.platforms.base import (
     BasePlatformAdapter,
     MessageEvent,
     MessageType,
+    ProcessingOutcome,
     SendResult,
     cache_image_from_bytes,
     cache_audio_from_bytes,
@@ -2732,7 +2733,7 @@ class TelegramAdapter(BasePlatformAdapter):
         if chat_id and message_id:
             await self._set_reaction(chat_id, message_id, "\U0001f440")
 
-    async def on_processing_complete(self, event: MessageEvent, success: bool) -> None:
+    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
         """Swap the in-progress reaction for a final success/failure reaction.
 
         Unlike Discord (additive reactions), Telegram's set_message_reaction
@@ -2742,5 +2743,9 @@ class TelegramAdapter(BasePlatformAdapter):
             return
         chat_id = getattr(event.source, "chat_id", None)
         message_id = getattr(event, "message_id", None)
-        if chat_id and message_id:
-            await self._set_reaction(chat_id, message_id, "\u2705" if success else "\u274c")
+        if chat_id and message_id and outcome != ProcessingOutcome.CANCELLED:
+            await self._set_reaction(
+                chat_id,
+                message_id,
+                "\u2705" if outcome == ProcessingOutcome.SUCCESS else "\u274c",
+            )
diff --git a/tests/gateway/test_base_topic_sessions.py b/tests/gateway/test_base_topic_sessions.py
index 37e00b279..901bc3468 100644
--- a/tests/gateway/test_base_topic_sessions.py
+++ b/tests/gateway/test_base_topic_sessions.py
@@ -6,7 +6,7 @@ from types import SimpleNamespace
 import pytest
 
 from gateway.config import Platform, PlatformConfig
-from gateway.platforms.base import BasePlatformAdapter, MessageEvent, SendResult
+from gateway.platforms.base import BasePlatformAdapter, MessageEvent, ProcessingOutcome, SendResult
 from gateway.session import SessionSource, build_session_key
 
 
@@ -44,8 +44,8 @@ class DummyTelegramAdapter(BasePlatformAdapter):
     async def on_processing_start(self, event: MessageEvent) -> None:
         self.processing_hooks.append(("start", event.message_id))
 
-    async def on_processing_complete(self, event: MessageEvent, success: bool) -> None:
-        self.processing_hooks.append(("complete", event.message_id, success))
+    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
+        self.processing_hooks.append(("complete", event.message_id, outcome))
 
 
 def _make_event(chat_id: str, thread_id: str, message_id: str = "1") -> MessageEvent:
@@ -142,7 +142,7 @@ class TestBasePlatformTopicSessions:
         ]
         assert adapter.processing_hooks == [
             ("start", "1"),
-            ("complete", "1", True),
+            ("complete", "1", ProcessingOutcome.SUCCESS),
         ]
 
     @pytest.mark.asyncio
@@ -168,7 +168,7 @@ class TestBasePlatformTopicSessions:
 
         assert adapter.processing_hooks == [
             ("start", "1"),
-            ("complete", "1", False),
+            ("complete", "1", ProcessingOutcome.FAILURE),
         ]
 
     @pytest.mark.asyncio
@@ -190,7 +190,7 @@ class TestBasePlatformTopicSessions:
 
         assert adapter.processing_hooks == [
             ("start", "1"),
-            ("complete", "1", False),
+            ("complete", "1", ProcessingOutcome.FAILURE),
         ]
 
     @pytest.mark.asyncio
@@ -218,5 +218,31 @@ class TestBasePlatformTopicSessions:
 
         assert adapter.processing_hooks == [
             ("start", "1"),
-            ("complete", "1", False),
+            ("complete", "1", ProcessingOutcome.FAILURE),
+        ]
+
+    @pytest.mark.asyncio
+    async def test_cancel_background_tasks_marks_expected_cancellation_cancelled(self):
+        adapter = DummyTelegramAdapter()
+        release = asyncio.Event()
+
+        async def handler(_event):
+            await release.wait()
+            return "ack"
+
+        async def hold_typing(_chat_id, interval=2.0, metadata=None):
+            await asyncio.Event().wait()
+
+        adapter.set_message_handler(handler)
+        adapter._keep_typing = hold_typing
+
+        event = _make_event("-1001", "17585")
+        await adapter.handle_message(event)
+        await asyncio.sleep(0)
+
+        await adapter.cancel_background_tasks()
+
+        assert adapter.processing_hooks == [
+            ("start", "1"),
+            ("complete", "1", ProcessingOutcome.CANCELLED),
         ]
diff --git a/tests/gateway/test_discord_reactions.py b/tests/gateway/test_discord_reactions.py
index 3988c67b5..2d7b2a2c9 100644
--- a/tests/gateway/test_discord_reactions.py
+++ b/tests/gateway/test_discord_reactions.py
@@ -8,7 +8,7 @@ from unittest.mock import AsyncMock, MagicMock
 import pytest
 
 from gateway.config import Platform, PlatformConfig
-from gateway.platforms.base import MessageEvent, MessageType, SendResult
+from gateway.platforms.base import MessageEvent, MessageType, ProcessingOutcome, SendResult
 from gateway.session import SessionSource, build_session_key
 
 
@@ -212,7 +212,7 @@ async def test_reactions_disabled_via_env_zero(adapter, monkeypatch):
 
     event = _make_event("5", raw_message)
     await adapter.on_processing_start(event)
-    await adapter.on_processing_complete(event, success=True)
+    await adapter.on_processing_complete(event, ProcessingOutcome.SUCCESS)
 
     raw_message.add_reaction.assert_not_awaited()
     raw_message.remove_reaction.assert_not_awaited()
@@ -232,3 +232,17 @@ async def test_reactions_enabled_by_default(adapter, monkeypatch):
     await adapter.on_processing_start(event)
 
     raw_message.add_reaction.assert_awaited_once_with("👀")
+
+
+@pytest.mark.asyncio
+async def test_on_processing_complete_cancelled_removes_eyes_without_terminal_reaction(adapter):
+    raw_message = SimpleNamespace(
+        add_reaction=AsyncMock(),
+        remove_reaction=AsyncMock(),
+    )
+
+    event = _make_event("7", raw_message)
+    await adapter.on_processing_complete(event, ProcessingOutcome.CANCELLED)
+
+    raw_message.remove_reaction.assert_awaited_once_with("👀", adapter._client.user)
+    raw_message.add_reaction.assert_not_awaited()
diff --git a/tests/gateway/test_matrix.py b/tests/gateway/test_matrix.py
index 0de00b736..09cdd8a44 100644
--- a/tests/gateway/test_matrix.py
+++ b/tests/gateway/test_matrix.py
@@ -1980,7 +1980,7 @@ class TestMatrixReactions:
 
     @pytest.mark.asyncio
     async def test_on_processing_complete_sends_check(self):
-        from gateway.platforms.base import MessageEvent, MessageType
+        from gateway.platforms.base import MessageEvent, MessageType, ProcessingOutcome
 
         self.adapter._reactions_enabled = True
         self.adapter._send_reaction = AsyncMock(return_value=True)
@@ -1994,9 +1994,28 @@ class TestMatrixReactions:
             raw_message={},
             message_id="$msg1",
         )
-        await self.adapter.on_processing_complete(event, success=True)
+        await self.adapter.on_processing_complete(event, ProcessingOutcome.SUCCESS)
         self.adapter._send_reaction.assert_called_once_with("!room:ex", "$msg1", "✅")
 
+    @pytest.mark.asyncio
+    async def test_on_processing_complete_cancelled_sends_no_terminal_reaction(self):
+        from gateway.platforms.base import MessageEvent, MessageType, ProcessingOutcome
+
+        self.adapter._reactions_enabled = True
+        self.adapter._send_reaction = AsyncMock(return_value=True)
+
+        source = MagicMock()
+        source.chat_id = "!room:ex"
+        event = MessageEvent(
+            text="hello",
+            message_type=MessageType.TEXT,
+            source=source,
+            raw_message={},
+            message_id="$msg1",
+        )
+        await self.adapter.on_processing_complete(event, ProcessingOutcome.CANCELLED)
+        self.adapter._send_reaction.assert_not_called()
+
     @pytest.mark.asyncio
     async def test_reactions_disabled(self):
         from gateway.platforms.base import MessageEvent, MessageType
diff --git a/tests/gateway/test_telegram_reactions.py b/tests/gateway/test_telegram_reactions.py
index 5068adb9f..98a75afbe 100644
--- a/tests/gateway/test_telegram_reactions.py
+++ b/tests/gateway/test_telegram_reactions.py
@@ -6,7 +6,7 @@ from unittest.mock import AsyncMock
 import pytest
 
 from gateway.config import Platform, PlatformConfig
-from gateway.platforms.base import MessageEvent, MessageType
+from gateway.platforms.base import MessageEvent, MessageType, ProcessingOutcome
 from gateway.session import SessionSource
 
 
@@ -180,7 +180,7 @@ async def test_on_processing_complete_success(monkeypatch):
     adapter = _make_adapter()
     event = _make_event()
 
-    await adapter.on_processing_complete(event, success=True)
+    await adapter.on_processing_complete(event, ProcessingOutcome.SUCCESS)
 
     adapter._bot.set_message_reaction.assert_awaited_once_with(
         chat_id=123,
@@ -196,7 +196,7 @@ async def test_on_processing_complete_failure(monkeypatch):
     adapter = _make_adapter()
     event = _make_event()
 
-    await adapter.on_processing_complete(event, success=False)
+    await adapter.on_processing_complete(event, ProcessingOutcome.FAILURE)
 
     adapter._bot.set_message_reaction.assert_awaited_once_with(
         chat_id=123,
@@ -212,7 +212,19 @@ async def test_on_processing_complete_skipped_when_disabled(monkeypatch):
     adapter = _make_adapter()
     event = _make_event()
 
-    await adapter.on_processing_complete(event, success=True)
+    await adapter.on_processing_complete(event, ProcessingOutcome.SUCCESS)
+
+    adapter._bot.set_message_reaction.assert_not_awaited()
+
+
+@pytest.mark.asyncio
+async def test_on_processing_complete_cancelled_keeps_existing_reaction(monkeypatch):
+    """Expected cancellation should not replace the in-progress reaction."""
+    monkeypatch.setenv("TELEGRAM_REACTIONS", "true")
+    adapter = _make_adapter()
+    event = _make_event()
+
+    await adapter.on_processing_complete(event, ProcessingOutcome.CANCELLED)
 
     adapter._bot.set_message_reaction.assert_not_awaited()