diff --git a/.github/workflows/hassfest.yaml b/.github/workflows/hassfest.yaml
index 1526864..14a5c70 100644
--- a/.github/workflows/hassfest.yaml
+++ b/.github/workflows/hassfest.yaml
@@ -35,11 +35,6 @@ jobs:
       - name: Run hassfest validation
         uses: home-assistant/actions/hassfest@master
 
-      - name: Print hassfest version
-        if: always()
-        run: |
-          echo "Hassfest version: $(hassfest --version)"
-
     concurrency:
       group: ${{ github.workflow }}-${{ github.ref }}
       cancel-in-progress: true
diff --git a/custom_components/ha_text_ai/__init__.py b/custom_components/ha_text_ai/__init__.py
index c41d001..eded54f 100644
--- a/custom_components/ha_text_ai/__init__.py
+++ b/custom_components/ha_text_ai/__init__.py
@@ -16,7 +16,7 @@ import asyncio
 import voluptuous as vol
 
 from homeassistant.config_entries import ConfigEntry
-from homeassistant.const import CONF_API_KEY, CONF_NAME
+from homeassistant.const import CONF_API_KEY, CONF_NAME, EVENT_HOMEASSISTANT_CLOSE
 from homeassistant.core import HomeAssistant, ServiceCall, SupportsResponse
 from homeassistant.exceptions import ConfigEntryNotReady, HomeAssistantError
 from homeassistant.helpers import config_validation as cv
@@ -379,6 +379,19 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
         # Register update listener for options changes
         entry.async_on_unload(entry.add_update_listener(async_update_options))
 
+        # HA Core stop does not unload entries, so close the dedicated
+        # session on the CLOSE event too; unload removes this listener
+        # and closes the session via APIClient.shutdown() instead.
+        async def _async_close_session_on_stop(_event) -> None:
+            if not session.closed:
+                await session.close()
+
+        entry.async_on_unload(
+            hass.bus.async_listen_once(
+                EVENT_HOMEASSISTANT_CLOSE, _async_close_session_on_stop
+            )
+        )
+
         _LOGGER.debug("Setup completed for %s", instance_name)
 
         return True
diff --git a/custom_components/ha_text_ai/utils.py b/custom_components/ha_text_ai/utils.py
index 887e4e2..3d069b3 100644
--- a/custom_components/ha_text_ai/utils.py
+++ b/custom_components/ha_text_ai/utils.py
@@ -17,7 +17,6 @@ from urllib.parse import urlparse
 
 import aiohttp
 from aiohttp.abc import AbstractResolver
-from aiohttp.resolver import DefaultResolver
 
 from homeassistant.const import CONF_API_KEY
 from homeassistant.core import HomeAssistant
@@ -86,10 +85,8 @@ class _PinnedResolver(AbstractResolver):
     def __init__(
         self,
         pinned: dict[str, list[tuple[str, int]]],
-        fallback: AbstractResolver | None = None,
     ) -> None:
         self._pinned = pinned
-        self._fallback = fallback or DefaultResolver()
 
     async def resolve(
         self,
@@ -99,7 +96,11 @@ class _PinnedResolver(AbstractResolver):
     ) -> list[dict[str, Any]]:
         entries = self._pinned.get(host.lower())
         if entries is None:
-            return await self._fallback.resolve(host, port, family)
+            # Every request on a pinned session must target the validated
+            # host. Resolving anything else means a request escaped the pin
+            # (a new call site or a config bug) — fail closed rather than
+            # fall back to live, unvalidated DNS.
+            raise OSError(f"Refusing to resolve unpinned host: {host}")
         return [
             {
                 "hostname": host,
@@ -113,7 +114,7 @@ class _PinnedResolver(AbstractResolver):
         ]
 
     async def close(self) -> None:
-        await self._fallback.close()
+        """Nothing to close; the resolver holds only the pinned map."""
 
 def _family_for(ip: str) -> int:
     """Return AF_INET or AF_INET6 based on the IP literal."""