diff --git a/homeassistant/components/conversation/icons.json b/homeassistant/components/conversation/icons.json
index 658783f9ae2..55bacf838a8 100644
--- a/homeassistant/components/conversation/icons.json
+++ b/homeassistant/components/conversation/icons.json
@@ -1,4 +1,9 @@
 {
+  "entity_component": {
+    "_": {
+      "default": "mdi:forum-outline"
+    }
+  },
   "services": {
     "process": {
       "service": "mdi:message-processing"
diff --git a/homeassistant/components/conversation/manifest.json b/homeassistant/components/conversation/manifest.json
index 36db24ce545..8101f8c8b5f 100644
--- a/homeassistant/components/conversation/manifest.json
+++ b/homeassistant/components/conversation/manifest.json
@@ -4,7 +4,7 @@
   "codeowners": ["@home-assistant/core", "@synesthesiam", "@arturpragacz"],
   "dependencies": ["http", "intent"],
   "documentation": "https://www.home-assistant.io/integrations/conversation",
-  "integration_type": "system",
+  "integration_type": "entity",
   "quality_scale": "internal",
   "requirements": ["hassil==3.2.0", "home-assistant-intents==2025.9.3"]
 }
diff --git a/homeassistant/const.py b/homeassistant/const.py
index 913ef5e177f..3c9de2af87c 100644
--- a/homeassistant/const.py
+++ b/homeassistant/const.py
@@ -6,6 +6,7 @@ from enum import StrEnum
 from functools import partial
 from typing import TYPE_CHECKING, Final
 
+from .generated.entity_platforms import EntityPlatforms
 from .helpers.deprecation import (
     DeprecatedConstant,
     DeprecatedConstantEnum,
@@ -36,54 +37,8 @@ REQUIRED_NEXT_PYTHON_HA_RELEASE: Final = ""
 # Format for platform files
 PLATFORM_FORMAT: Final = "{platform}.{domain}"
 
-
-class Platform(StrEnum):
-    """Available entity platforms."""
-
-    AI_TASK = "ai_task"
-    AIR_QUALITY = "air_quality"
-    ALARM_CONTROL_PANEL = "alarm_control_panel"
-    ASSIST_SATELLITE = "assist_satellite"
-    BINARY_SENSOR = "binary_sensor"
-    BUTTON = "button"
-    CALENDAR = "calendar"
-    CAMERA = "camera"
-    CLIMATE = "climate"
-    CONVERSATION = "conversation"
-    COVER = "cover"
-    DATE = "date"
-    DATETIME = "datetime"
-    DEVICE_TRACKER = "device_tracker"
-    EVENT = "event"
-    FAN = "fan"
-    GEO_LOCATION = "geo_location"
-    HUMIDIFIER = "humidifier"
-    IMAGE = "image"
-    IMAGE_PROCESSING = "image_processing"
-    LAWN_MOWER = "lawn_mower"
-    LIGHT = "light"
-    LOCK = "lock"
-    MEDIA_PLAYER = "media_player"
-    NOTIFY = "notify"
-    NUMBER = "number"
-    REMOTE = "remote"
-    SCENE = "scene"
-    SELECT = "select"
-    SENSOR = "sensor"
-    SIREN = "siren"
-    STT = "stt"
-    SWITCH = "switch"
-    TEXT = "text"
-    TIME = "time"
-    TODO = "todo"
-    TTS = "tts"
-    UPDATE = "update"
-    VACUUM = "vacuum"
-    VALVE = "valve"
-    WAKE_WORD = "wake_word"
-    WATER_HEATER = "water_heater"
-    WEATHER = "weather"
-
+# Type alias to avoid 1000 MyPy errors
+Platform = EntityPlatforms
 
 BASE_PLATFORMS: Final = {platform.value for platform in Platform}
 
diff --git a/homeassistant/generated/entity_platforms.py b/homeassistant/generated/entity_platforms.py
new file mode 100644
index 00000000000..7010ffc9be7
--- /dev/null
+++ b/homeassistant/generated/entity_platforms.py
@@ -0,0 +1,54 @@
+"""Automatically generated file.
+
+To update, run python3 -m script.hassfest
+"""
+
+from enum import StrEnum
+
+
+class EntityPlatforms(StrEnum):
+    """Available entity platforms."""
+
+    AI_TASK = "ai_task"
+    AIR_QUALITY = "air_quality"
+    ALARM_CONTROL_PANEL = "alarm_control_panel"
+    ASSIST_SATELLITE = "assist_satellite"
+    BINARY_SENSOR = "binary_sensor"
+    BUTTON = "button"
+    CALENDAR = "calendar"
+    CAMERA = "camera"
+    CLIMATE = "climate"
+    CONVERSATION = "conversation"
+    COVER = "cover"
+    DATE = "date"
+    DATETIME = "datetime"
+    DEVICE_TRACKER = "device_tracker"
+    EVENT = "event"
+    FAN = "fan"
+    GEO_LOCATION = "geo_location"
+    HUMIDIFIER = "humidifier"
+    IMAGE = "image"
+    IMAGE_PROCESSING = "image_processing"
+    LAWN_MOWER = "lawn_mower"
+    LIGHT = "light"
+    LOCK = "lock"
+    MEDIA_PLAYER = "media_player"
+    NOTIFY = "notify"
+    NUMBER = "number"
+    REMOTE = "remote"
+    SCENE = "scene"
+    SELECT = "select"
+    SENSOR = "sensor"
+    SIREN = "siren"
+    STT = "stt"
+    SWITCH = "switch"
+    TEXT = "text"
+    TIME = "time"
+    TODO = "todo"
+    TTS = "tts"
+    UPDATE = "update"
+    VACUUM = "vacuum"
+    VALVE = "valve"
+    WAKE_WORD = "wake_word"
+    WATER_HEATER = "water_heater"
+    WEATHER = "weather"
diff --git a/script/hassfest/__main__.py b/script/hassfest/__main__.py
index dfa99c6bc75..43a6cc7678b 100644
--- a/script/hassfest/__main__.py
+++ b/script/hassfest/__main__.py
@@ -19,6 +19,7 @@ from . import (
     dhcp,
     docker,
     icons,
+    integration_info,
     json,
     manifest,
     metadata,
@@ -44,6 +45,7 @@ INTEGRATION_PLUGINS = [
     dependencies,
     dhcp,
     icons,
+    integration_info,
     json,
     manifest,
     mqtt,
diff --git a/script/hassfest/integration_info.py b/script/hassfest/integration_info.py
new file mode 100644
index 00000000000..8747e256be7
--- /dev/null
+++ b/script/hassfest/integration_info.py
@@ -0,0 +1,42 @@
+"""Write integration constants."""
+
+from __future__ import annotations
+
+from .model import Config, Integration
+from .serializer import format_python
+
+
+def validate(integrations: dict[str, Integration], config: Config) -> None:
+    """Validate integrations file."""
+
+    if config.specific_integrations:
+        return
+
+    int_type = "entity"
+
+    domains = [
+        integration.domain
+        for integration in integrations.values()
+        if integration.manifest.get("integration_type") == int_type
+        # Tag is type "entity" but has no entity platform
+        and integration.domain != "tag"
+    ]
+
+    code = [
+        "from enum import StrEnum",
+        "class EntityPlatforms(StrEnum):",
+        f'    """Available {int_type} platforms."""',
+    ]
+    code.extend([f'    {domain.upper()} = "{domain}"' for domain in sorted(domains)])
+
+    config.cache[f"integrations_{int_type}"] = format_python(
+        "\n".join(code), generator="script.hassfest"
+    )
+
+
+def generate(integrations: dict[str, Integration], config: Config) -> None:
+    """Generate integration file."""
+    int_type = "entity"
+    filename = "entity_platforms"
+    platform_path = config.root / f"homeassistant/generated/{filename}.py"
+    platform_path.write_text(config.cache[f"integrations_{int_type}"])
diff --git a/tests/components/knx/test_config_store.py b/tests/components/knx/test_config_store.py
index bb6af6408b8..8f11888d1f2 100644
--- a/tests/components/knx/test_config_store.py
+++ b/tests/components/knx/test_config_store.py
@@ -88,7 +88,7 @@ async def test_create_entity_error(
     assert res["success"], res
     assert not res["result"]["success"]
     assert res["result"]["errors"][0]["path"] == ["platform"]
-    assert res["result"]["error_base"].startswith("expected Platform or one of")
+    assert res["result"]["error_base"].startswith("expected EntityPlatforms or one of")
 
     # create entity with unsupported platform
     await client.send_json_auto_id(