diff --git a/custom_components/ha_text_ai/__init__.py b/custom_components/ha_text_ai/__init__.py
index cbb47fd..284fe14 100644
--- a/custom_components/ha_text_ai/__init__.py
+++ b/custom_components/ha_text_ai/__init__.py
@@ -9,24 +9,23 @@ The HA Text AI integration.
 from __future__ import annotations
 
 import logging
-import os
-import shutil
-from datetime import datetime, timedelta
-from typing import Any, Dict, TypeVar
+from datetime import datetime
+from typing import Any, Dict
+
+import asyncio
 
 import voluptuous as vol
-from async_timeout import timeout
 
 from homeassistant.config_entries import ConfigEntry
-from homeassistant.const import CONF_API_KEY, CONF_NAME, Platform
-from homeassistant.core import HomeAssistant, ServiceCall
+from homeassistant.const import CONF_API_KEY, CONF_NAME
+from homeassistant.core import HomeAssistant, ServiceCall, SupportsResponse
 from homeassistant.exceptions import ConfigEntryNotReady, HomeAssistantError
 from homeassistant.helpers import config_validation as cv
 from homeassistant.helpers import aiohttp_client
 
 from .coordinator import HATextAICoordinator
 from .api_client import APIClient
-from .utils import get_file_hash, safe_log_data
+from .utils import safe_log_data, validate_endpoint
 from .providers import get_default_endpoint, get_default_model, build_auth_headers
 from .const import (
     DOMAIN,
@@ -53,24 +52,24 @@ from .const import (
     SERVICE_SET_SYSTEM_PROMPT,
     DEFAULT_MAX_HISTORY,
     CONF_MAX_HISTORY_SIZE,
-    ICONS_SUBDOMAIN,
 )
 
 _LOGGER = logging.getLogger(__name__)
 
 CONFIG_SCHEMA = cv.config_entry_only_config_schema(DOMAIN)
-ConfigType = TypeVar("ConfigType", bound=Dict[str, Any])
 
 SERVICE_SCHEMA_ASK_QUESTION = vol.Schema({
     vol.Required("instance"): cv.string,
-    vol.Required("question"): cv.string,
-    vol.Optional("system_prompt"): cv.string,
+    vol.Required("question"): vol.All(cv.string, vol.Length(min=1, max=100000)),
+    vol.Optional("system_prompt"): vol.All(cv.string, vol.Length(max=50000)),
     vol.Optional("model"): cv.string,
-    vol.Optional("temperature"): cv.positive_float,
+    vol.Optional("temperature"): vol.All(
+        vol.Coerce(float), vol.Range(min=0.0, max=2.0)
+    ),
     vol.Optional("max_tokens"): cv.positive_int,
     vol.Optional("context_messages"): cv.positive_int,
     vol.Optional("structured_output", default=False): cv.boolean,
-    vol.Optional("json_schema"): cv.string,
+    vol.Optional("json_schema"): vol.All(cv.string, vol.Length(max=50000)),
 })
 
 SERVICE_SCHEMA_SET_SYSTEM_PROMPT = vol.Schema({
@@ -98,7 +97,7 @@ def get_coordinator_by_instance(hass: HomeAssistant, instance: str) -> HATextAIC
 
     raise HomeAssistantError(f"Instance {instance} not found")
 
-async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
+async def async_setup(hass: HomeAssistant, config: Dict[str, Any]) -> bool:
     """Set up the Home Assistant Text AI component."""
     # Initialize domain data storage
     hass.data.setdefault(DOMAIN, {})
@@ -143,7 +142,7 @@ async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
                 "question": call.data["question"],
                 "timestamp": datetime.now().isoformat(),
                 "success": False,
-                "error": str(err)
+                "error": "Service call failed"
             }
 
     async def async_clear_history(call: ServiceCall) -> None:
@@ -185,7 +184,7 @@ async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
         SERVICE_ASK_QUESTION,
         async_ask_question,
         schema=SERVICE_SCHEMA_ASK_QUESTION,
-        supports_response=True
+        supports_response=SupportsResponse.OPTIONAL
     )
 
     hass.services.async_register(
@@ -199,7 +198,8 @@ async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
         DOMAIN,
         SERVICE_GET_HISTORY,
         async_get_history,
-        schema=SERVICE_SCHEMA_GET_HISTORY
+        schema=SERVICE_SCHEMA_GET_HISTORY,
+        supports_response=SupportsResponse.OPTIONAL
     )
 
     hass.services.async_register(
@@ -209,53 +209,6 @@ async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
         schema=SERVICE_SCHEMA_SET_SYSTEM_PROMPT
     )
 
-    # Handle icons
-    try:
-        source_icon_path = os.path.join(
-            os.path.dirname(__file__),
-            ICONS_SUBDOMAIN,
-            'icon@2x.png'
-        )
-
-        destination_directory = os.path.join(
-            hass.config.path('www'),
-            DOMAIN,
-            ICONS_SUBDOMAIN
-        )
-
-        destination_icon_path = os.path.join(
-            destination_directory,
-            'icon.png'
-        )
-
-        if not os.path.exists(source_icon_path):
-            _LOGGER.error("Source icon not found: %s", source_icon_path)
-            return True
-
-        def create_directory():
-            os.makedirs(destination_directory, exist_ok=True)
-
-        await hass.async_add_executor_job(create_directory)
-
-        should_copy = True
-
-        if os.path.exists(destination_icon_path):
-            source_hash = await hass.async_add_executor_job(get_file_hash, source_icon_path)
-            dest_hash = await hass.async_add_executor_job(get_file_hash, destination_icon_path)
-            should_copy = source_hash != dest_hash
-
-        if should_copy:
-            def copy_file():
-                shutil.copyfile(source_icon_path, destination_icon_path)
-
-            await hass.async_add_executor_job(copy_file)
-            _LOGGER.debug("Icon updated: %s", destination_icon_path)
-
-    except PermissionError as e:
-        _LOGGER.error("Permission denied when managing icons: %s", str(e))
-    except Exception as e:
-        _LOGGER.error("Failed to manage icons: %s", str(e))
-
     return True
 
 async def async_check_api(session, endpoint: str, headers: dict, provider: str, api_timeout: int = DEFAULT_API_TIMEOUT) -> bool:
@@ -275,9 +228,9 @@ async def async_check_api(session, endpoint: str, headers: dict, provider: str,
         else:  # OpenAI
             check_url = f"{endpoint}/models"
 
-        async with timeout(api_timeout):
+        async with asyncio.timeout(api_timeout):
             async with session.get(check_url, headers=headers) as response:
-                if response.status in [200, 404]:
+                if response.status == 200:
                     return True
                 elif response.status == 401:
                     _LOGGER.error("Invalid API key")
@@ -294,7 +247,7 @@ async def async_check_api(session, endpoint: str, headers: dict, provider: str,
 
 async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     """Set up HA Text AI from a config entry."""
-    _LOGGER.debug(f"Setting up HA Text AI entry: {entry.data}")
+    _LOGGER.debug("Setting up HA Text AI entry: %s", safe_log_data(dict(entry.data)))
 
     try:
         # Get provider from data or options (options takes precedence)
@@ -308,7 +261,12 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
         session = aiohttp_client.async_get_clientsession(hass)
 
         model = config.get(CONF_MODEL, get_default_model(api_provider))
-        endpoint = config.get(CONF_API_ENDPOINT, get_default_endpoint(api_provider)).rstrip('/')
+        raw_endpoint = config.get(CONF_API_ENDPOINT, get_default_endpoint(api_provider))
+        try:
+            endpoint = validate_endpoint(raw_endpoint)
+        except ValueError as err:
+            _LOGGER.error("Invalid API endpoint %s: %s", raw_endpoint, err)
+            raise ConfigEntryNotReady(f"Invalid API endpoint: {err}")
         # API key can now be updated via options
         api_key = config.get(CONF_API_KEY, entry.data.get(CONF_API_KEY))
         instance_name = entry.data.get(CONF_NAME, entry.entry_id)
@@ -350,13 +308,16 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
             api_timeout=api_timeout,
         )
 
-        _LOGGER.debug(f"Created coordinator for {instance_name}")
+        # Initialize coordinator (directories, history, metrics)
+        await coordinator.async_initialize()
+
+        _LOGGER.debug("Created coordinator for %s", instance_name)
 
         # Store coordinator
         hass.data.setdefault(DOMAIN, {})
         hass.data[DOMAIN][entry.entry_id] = coordinator
 
-        _LOGGER.debug(f"Stored coordinator in hass.data[{DOMAIN}][{entry.entry_id}]")
+        _LOGGER.debug("Stored coordinator in hass.data[%s][%s]", DOMAIN, entry.entry_id)
 
         # Set up platforms
         await hass.config_entries.async_forward_entry_setups(entry, PLATFORMS)
@@ -364,12 +325,12 @@ 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))
 
-        _LOGGER.debug(f"Setup completed for {instance_name}")
+        _LOGGER.debug("Setup completed for %s", instance_name)
 
         return True
 
     except Exception as err:
-        _LOGGER.exception(f"Error setting up HA Text AI: {err}")
+        _LOGGER.exception("Error setting up HA Text AI: %s", err)
         raise
 
 async def async_update_options(hass: HomeAssistant, entry: ConfigEntry) -> None:
diff --git a/custom_components/ha_text_ai/api_client.py b/custom_components/ha_text_ai/api_client.py
index 7e05ec4..b1a4c22 100644
--- a/custom_components/ha_text_ai/api_client.py
+++ b/custom_components/ha_text_ai/api_client.py
@@ -10,10 +10,7 @@ import logging
 import asyncio
 from typing import Any, Dict, List, Optional
 from aiohttp import ClientSession, ClientTimeout
-from async_timeout import timeout
-from datetime import datetime, timedelta
 
-from homeassistant.core import HomeAssistant
 from homeassistant.exceptions import HomeAssistantError
 from .const import (
     DEFAULT_API_TIMEOUT,
@@ -88,38 +85,58 @@ class APIClient:
         url: str,
         payload: Dict[str, Any],
     ) -> Dict[str, Any]:
-        """Make API request with retry logic."""
-        # Log request without sensitive data
+        """Make API request with retry logic for transient errors only."""
         safe_payload = {k: v for k, v in payload.items() if k not in ['messages', 'system']}
-        _LOGGER.debug(f"API Request: URL={url}, Safe payload: {safe_payload}")
-        
+        _LOGGER.debug("API Request: URL=%s, Safe payload: %s", url, safe_payload)
+
         for attempt in range(API_RETRY_COUNT):
             try:
-                async with timeout(self.api_timeout):
-                    async with self.session.post(
-                        url,
-                        json=payload,
-                        headers=self.headers,
-                        timeout=self.timeout,
-                    ) as response:
-                        _LOGGER.debug(f"Response status: {response.status}")
-                        if response.status != 200:
-                            error_data = await response.json()
-                            # Log error without sensitive data
-                            safe_error = {k: v for k, v in error_data.items() if k not in ['message', 'details']}
-                            _LOGGER.error(f"API error (status {response.status}): {safe_error}")
-                            raise HomeAssistantError(f"API error: status {response.status}")
+                async with self.session.post(
+                    url,
+                    json=payload,
+                    headers=self.headers,
+                    timeout=self.timeout,
+                ) as response:
+                    _LOGGER.debug("Response status: %s", response.status)
+                    if response.status == 200:
                         return await response.json()
+
+                    # Try to get error details
+                    error_data = {}
+                    try:
+                        error_data = await response.json()
+                    except Exception:
+                        error_data = {"raw": await response.text()}
+
+                    # Rate limit — retry with backoff
+                    if response.status == 429:
+                        _LOGGER.warning(
+                            "Rate limit on attempt %d/%d", attempt + 1, API_RETRY_COUNT
+                        )
+                        if attempt < API_RETRY_COUNT - 1:
+                            await asyncio.sleep(2 ** attempt)
+                            continue
+                        raise HomeAssistantError("API rate limit exceeded")
+
+                    # Client/server errors — don't retry
+                    _LOGGER.error("API error (status %d): %s", response.status, error_data)
+                    raise HomeAssistantError(f"API error: status {response.status}")
+
             except asyncio.TimeoutError:
-                _LOGGER.warning(f"Timeout on attempt {attempt + 1}/{API_RETRY_COUNT}")
+                _LOGGER.warning("Timeout on attempt %d/%d", attempt + 1, API_RETRY_COUNT)
                 if attempt == API_RETRY_COUNT - 1:
                     raise HomeAssistantError("API request timed out")
-                await asyncio.sleep(1 * (attempt + 1))
+                await asyncio.sleep(2 ** attempt)
+            except HomeAssistantError:
+                raise
             except Exception as e:
-                _LOGGER.warning(f"API request failed on attempt {attempt + 1}/{API_RETRY_COUNT}: {type(e).__name__}")
+                _LOGGER.warning(
+                    "API request failed on attempt %d/%d: %s",
+                    attempt + 1, API_RETRY_COUNT, type(e).__name__,
+                )
                 if attempt == API_RETRY_COUNT - 1:
                     raise
-                await asyncio.sleep(1 * (attempt + 1))
+                await asyncio.sleep(2 ** attempt)
 
     async def create(
         self,
@@ -320,15 +337,6 @@ class APIClient:
             },
         }
 
-    async def check_connection(self) -> bool:
-        """Check API connection."""
-        try:
-            await self._make_request(self.endpoint, {"test": "connection"})
-            return True
-        except Exception as e:
-            _LOGGER.error(f"Connection check failed: {str(e)}")
-            return False
-
     async def _create_gemini_completion(
         self,
         model: str,
diff --git a/custom_components/ha_text_ai/config_flow.py b/custom_components/ha_text_ai/config_flow.py
index 73fa2e4..9042680 100644
--- a/custom_components/ha_text_ai/config_flow.py
+++ b/custom_components/ha_text_ai/config_flow.py
@@ -49,7 +49,7 @@ from .const import (
     DEFAULT_MAX_HISTORY,
     CONF_MAX_HISTORY_SIZE,
 )
-from .utils import normalize_name  # noqa: F401 — re-exported for backward compat
+from .utils import normalize_name, safe_log_data, validate_endpoint  # noqa: F401 — re-exported for backward compat
 from .providers import get_default_endpoint, get_default_model
 
 _LOGGER = logging.getLogger(__name__)
@@ -132,16 +132,15 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                 })
             )
 
-        # Debug log to identify what's in the input
-        _LOGGER.debug(f"Provider step input data: {user_input}")
+        _LOGGER.debug("Provider step input data: %s", safe_log_data(user_input))
 
         input_copy = user_input.copy()
 
         # Check if CONF_NAME exists in input_copy and ensure it's not empty
         if CONF_NAME not in input_copy or not input_copy[CONF_NAME]:
-            _LOGGER.warning(f"Missing name in configuration input: {input_copy}")
-            input_copy[CONF_NAME] = f"gemini_assistant_{datetime.now().strftime('%Y%m%d_%H%M%S')}"
-            _LOGGER.info(f"Auto-generated name: {input_copy[CONF_NAME]}")
+            _LOGGER.warning("Missing name in configuration input: %s", safe_log_data(input_copy))
+            input_copy[CONF_NAME] = f"assistant_{datetime.now().strftime('%Y%m%d_%H%M%S')}"
+            _LOGGER.info("Auto-generated name: %s", input_copy[CONF_NAME])
 
         # Ensure API key is present
         if CONF_API_KEY not in input_copy or not input_copy[CONF_API_KEY]:
@@ -197,7 +196,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                 step_id="provider",
                 data_schema=vol.Schema({
                     vol.Required(CONF_NAME, default=input_copy.get(CONF_NAME, "my_assistant")): str,
-                    vol.Required(CONF_API_KEY, default=input_copy.get(CONF_API_KEY, "")): str,
+                    vol.Required(CONF_API_KEY): str,
                     vol.Required(CONF_MODEL, default=input_copy.get(CONF_MODEL, get_default_model(self._provider))): str,
                     vol.Required(CONF_API_ENDPOINT, default=input_copy.get(CONF_API_ENDPOINT, get_default_endpoint(self._provider))): str,
                     vol.Optional(CONF_TEMPERATURE, default=input_copy.get(CONF_TEMPERATURE, DEFAULT_TEMPERATURE)): vol.All(
@@ -259,7 +258,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                         step_id="provider",
                         data_schema=vol.Schema({
                             vol.Required(CONF_NAME, default=input_copy.get(CONF_NAME, "my_assistant")): str,
-                            vol.Required(CONF_API_KEY, default=input_copy.get(CONF_API_KEY, "")): str,
+                            vol.Required(CONF_API_KEY): str,
                             vol.Required(CONF_MODEL, default=input_copy.get(CONF_MODEL, get_default_model(self._provider))): str,
                             vol.Required(CONF_API_ENDPOINT, default=input_copy.get(CONF_API_ENDPOINT, get_default_endpoint(self._provider))): str,
                             vol.Optional(CONF_TEMPERATURE, default=input_copy.get(CONF_TEMPERATURE, DEFAULT_TEMPERATURE)): vol.All(
@@ -302,7 +301,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                 step_id="provider",
                 data_schema=vol.Schema({
                     vol.Required(CONF_NAME, default=input_copy.get(CONF_NAME, "my_assistant")): str,
-                    vol.Required(CONF_API_KEY, default=input_copy.get(CONF_API_KEY, "")): str,
+                    vol.Required(CONF_API_KEY): str,
                     vol.Required(CONF_MODEL, default=input_copy.get(CONF_MODEL, get_default_model(self._provider))): str,
                     vol.Required(CONF_API_ENDPOINT, default=input_copy.get(CONF_API_ENDPOINT, get_default_endpoint(self._provider))): str,
                     # Other fields remain the same
@@ -353,9 +352,16 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                 self._errors["base"] = "invalid_auth"
                 return False
 
+            # Validate endpoint URL (HTTPS-only, SSRF protection)
+            try:
+                endpoint = validate_endpoint(user_input[CONF_API_ENDPOINT])
+            except ValueError as err:
+                _LOGGER.error("Endpoint validation failed: %s", err)
+                self._errors["base"] = "cannot_connect"
+                return False
+
             session = async_get_clientsession(self.hass)
             headers = self._get_api_headers(user_input)
-            endpoint = user_input[CONF_API_ENDPOINT].rstrip('/')
 
             if self._provider == API_PROVIDER_GEMINI:
                 if not user_input[CONF_API_KEY]:
@@ -434,7 +440,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
             if key not in entry_data:
                 entry_data[key] = value
 
-        _LOGGER.debug(f"Creating config entry with data: {entry_data}")
+        _LOGGER.debug("Creating config entry with data: %s", safe_log_data(entry_data))
 
         return self.async_create_entry(
             title=instance_name,
@@ -484,13 +490,20 @@ class OptionsFlowHandler(config_entries.OptionsFlow):
                 self._errors["base"] = "invalid_auth"
                 return False
 
+            # Validate endpoint URL (HTTPS-only, SSRF protection)
+            try:
+                endpoint = validate_endpoint(endpoint)
+            except ValueError as err:
+                _LOGGER.error("Endpoint validation failed: %s", err)
+                self._errors["base"] = "cannot_connect"
+                return False
+
             # For Gemini, just check if API key is present
             if provider == API_PROVIDER_GEMINI:
                 return True
 
             session = async_get_clientsession(self.hass)
             headers = self._get_api_headers(api_key, provider)
-            endpoint = endpoint.rstrip('/')
 
             check_url = (
                 f"{endpoint}/v1/models" if provider == API_PROVIDER_ANTHROPIC
@@ -607,10 +620,7 @@ class OptionsFlowHandler(config_entries.OptionsFlow):
         data = user_input or current_data
 
         return vol.Schema({
-            vol.Required(
-                CONF_API_KEY,
-                default=data.get(CONF_API_KEY, "")
-            ): str,
+            vol.Required(CONF_API_KEY): str,
             vol.Required(
                 CONF_API_ENDPOINT,
                 default=data.get(CONF_API_ENDPOINT, default_endpoint)
diff --git a/custom_components/ha_text_ai/const.py b/custom_components/ha_text_ai/const.py
index cb245a0..bc02155 100644
--- a/custom_components/ha_text_ai/const.py
+++ b/custom_components/ha_text_ai/const.py
@@ -9,15 +9,13 @@ Constants for the HA text AI integration.
 import os
 import json
 from typing import Final
-import voluptuous as vol
 from homeassistant.const import Platform, CONF_API_KEY, CONF_NAME
-from homeassistant.helpers import config_validation as cv
 import logging
 _LOGGER = logging.getLogger(__name__)
 
 # Domain and platforms
 DOMAIN: Final = "ha_text_ai"
-PLATFORMS: list[str] = ["sensor"]
+PLATFORMS: list[Platform] = [Platform.SENSOR]
 
 # Provider configuration
 CONF_API_PROVIDER: Final = "api_provider"
@@ -72,11 +70,9 @@ CONF_JSON_SCHEMA: Final = "json_schema"
 ABSOLUTE_MAX_HISTORY_SIZE = 500
 MAX_ATTRIBUTE_SIZE = 4 * 1024
 MAX_HISTORY_FILE_SIZE = 1 * 1024 * 1024
-ICONS_SUBDOMAIN = "icons"
-
 # Default values
 DEFAULT_MODEL: Final = "gpt-4o-mini"
-DEFAULT_ANTHROPIC_MODEL: Final = "claude-3-5-sonnet"
+DEFAULT_ANTHROPIC_MODEL: Final = "claude-sonnet-4-6"
 DEFAULT_DEEPSEEK_MODEL: Final = "deepseek-chat"
 DEFAULT_GEMINI_MODEL: Final = "gemini-2.0-flash"
 DEFAULT_TEMPERATURE: Final = 0.1
@@ -184,74 +180,3 @@ STATE_DISCONNECTED: Final = "disconnected"
 EVENT_RESPONSE_RECEIVED: Final = f"{DOMAIN}_response_received"
 EVENT_ERROR_OCCURRED: Final = f"{DOMAIN}_error_occurred"
 EVENT_STATE_CHANGED: Final = f"{DOMAIN}_state_changed"
-
-# Service schema constants
-SERVICE_SCHEMA_ASK_QUESTION = vol.Schema({
-    vol.Required(CONF_INSTANCE): cv.string,
-    vol.Required("question"): cv.string,
-    vol.Optional("system_prompt"): cv.string,
-    vol.Optional("model"): cv.string,
-    vol.Optional("temperature"): vol.All(
-        vol.Coerce(float),
-        vol.Range(min=MIN_TEMPERATURE, max=MAX_TEMPERATURE)
-    ),
-    vol.Optional("max_tokens"): vol.All(
-        vol.Coerce(int),
-        vol.Range(min=MIN_MAX_TOKENS, max=MAX_MAX_TOKENS)
-    ),
-    vol.Optional("context_messages"): vol.All(
-        vol.Coerce(int),
-        vol.Range(min=1, max=20)
-    ),
-    vol.Optional(CONF_STRUCTURED_OUTPUT, default=False): cv.boolean,
-    vol.Optional(CONF_JSON_SCHEMA): cv.string,
-})
-
-SERVICE_SCHEMA_SET_SYSTEM_PROMPT = vol.Schema({
-    vol.Required(CONF_INSTANCE): cv.string,
-    vol.Required("prompt"): cv.string
-})
-
-SERVICE_SCHEMA_GET_HISTORY = vol.Schema({
-    vol.Required(CONF_INSTANCE): cv.string,
-    vol.Optional("limit", default=10): vol.All(
-        vol.Coerce(int),
-        vol.Range(min=1, max=100),
-    ),
-    vol.Optional("filter_model"): cv.string
-})
-
-# Configuration schema
-CONFIG_SCHEMA = vol.Schema({
-    DOMAIN: vol.Schema({
-        vol.Required(CONF_NAME): cv.string,
-        vol.Required(CONF_API_KEY): cv.string,
-        vol.Required(CONF_API_PROVIDER): vol.In(API_PROVIDERS),
-        vol.Optional(CONF_MODEL, default=DEFAULT_MODEL): cv.string,
-        vol.Optional(CONF_TEMPERATURE, default=DEFAULT_TEMPERATURE): vol.All(
-            vol.Coerce(float),
-            vol.Range(min=MIN_TEMPERATURE, max=MAX_TEMPERATURE)
-        ),
-        vol.Optional(CONF_MAX_TOKENS, default=DEFAULT_MAX_TOKENS): vol.All(
-            vol.Coerce(int),
-            vol.Range(min=MIN_MAX_TOKENS, max=MAX_MAX_TOKENS)
-        ),
-        vol.Optional(CONF_API_ENDPOINT): cv.string,
-        vol.Optional(CONF_REQUEST_INTERVAL, default=DEFAULT_REQUEST_INTERVAL): vol.All(
-            vol.Coerce(float),
-            vol.Range(min=MIN_REQUEST_INTERVAL, max=MAX_REQUEST_INTERVAL)
-        ),
-        vol.Optional(CONF_API_TIMEOUT, default=DEFAULT_API_TIMEOUT): vol.All(
-            vol.Coerce(int),
-            vol.Range(min=MIN_API_TIMEOUT, max=MAX_API_TIMEOUT)
-        ),
-        vol.Optional(CONF_MAX_HISTORY_SIZE, default=DEFAULT_MAX_HISTORY): vol.All(  # Correct usage
-            vol.Coerce(int),
-            vol.Range(min=1, max=100),
-        ),
-        vol.Optional(CONF_CONTEXT_MESSAGES, default=DEFAULT_CONTEXT_MESSAGES): vol.All(
-            vol.Coerce(int),
-            vol.Range(min=1, max=20)
-        )
-    })
-}, extra=vol.ALLOW_EXTRA)
diff --git a/custom_components/ha_text_ai/coordinator.py b/custom_components/ha_text_ai/coordinator.py
index d835878..998f819 100644
--- a/custom_components/ha_text_ai/coordinator.py
+++ b/custom_components/ha_text_ai/coordinator.py
@@ -14,8 +14,6 @@ import aiofiles
 import os
 import json
 import asyncio
-import psutil
-import re
 import math
 from datetime import datetime, timedelta
 from typing import Any, Dict, List, Optional, Union
@@ -116,6 +114,9 @@ class HATextAICoordinator(DataUpdateCoordinator):
         self.is_anthropic = is_anthropic
         self.api_timeout = api_timeout
 
+        # Concurrency control
+        self._request_lock = asyncio.Lock()
+
         # Initialize essential attributes
         self._is_processing = False
         self._is_rate_limited = False
@@ -170,14 +171,7 @@ class HATextAICoordinator(DataUpdateCoordinator):
             "ha_text_ai_history"
         )
 
-        # Initialize all async tasks in proper order
-        self.hass.async_create_task(self._create_history_dir())
-        self.hass.async_create_task(self._check_history_directory())
-        self.hass.async_create_task(self._initialize_metrics())
-        self.hass.async_create_task(self.async_initialize_history_file())
-        self.hass.async_create_task(self._migrate_history_from_txt_to_json())
-
-        # History file path using instance name
+        # History file path using instance name — must be set before async_initialize
         self._history_file = os.path.join(
             self._history_dir,
             f"{self.normalized_name}_history.json"
@@ -188,7 +182,15 @@ class HATextAICoordinator(DataUpdateCoordinator):
 
         self.context_messages = context_messages
 
-        _LOGGER.info(f"Initialized HA Text AI coordinator with instance: {instance_name}")
+        _LOGGER.info("Initialized HA Text AI coordinator with instance: %s", instance_name)
+
+    async def async_initialize(self) -> None:
+        """Initialize coordinator: directories, history, metrics. Must be awaited."""
+        await self._create_history_dir()
+        await self._check_history_directory()
+        await self._initialize_metrics()
+        await self.async_initialize_history_file()
+        await self._migrate_history_from_txt_to_json()
 
     @property
     def last_response(self) -> Dict[str, Any]:
@@ -357,7 +359,6 @@ class HATextAICoordinator(DataUpdateCoordinator):
             HomeAssistantError: {"is_ha_error": True},
             ConnectionError: {
                 "is_connection_error": True,
-                "is_rate_limited": True
             },
             TimeoutError: {"is_timeout": True},
             PermissionError: {"is_permission_denied": True},
@@ -529,67 +530,14 @@ class HATextAICoordinator(DataUpdateCoordinator):
             _LOGGER.error(f"Error checking file size for {file_path}: {e}")
             return 0
 
-    def _sync_write_history_entry(self, entry: dict) -> None:
-        """Synchronous method to write history entry with enhanced error handling."""
-        try:
-            history = []
-            if os.path.exists(self._history_file):
-                try:
-                    with open(self._history_file, 'r', encoding='utf-8') as f:
-                        content = f.read()
-                        if content.strip():
-                            history = json.loads(content)
-                except (json.JSONDecodeError, UnicodeDecodeError) as e:
-                    _LOGGER.warning(f"Corrupted history file, creating new: {e}")
-                    # Backup corrupted file
-                    backup_path = f"{self._history_file}.corrupted.{dt_util.utcnow().strftime('%Y%m%d_%H%M%S')}"
-                    try:
-                        os.rename(self._history_file, backup_path)
-                        _LOGGER.info(f"Corrupted history backed up to: {backup_path}")
-                    except OSError:
-                        pass
-                except PermissionError as e:
-                    _LOGGER.error(f"Permission denied reading history file: {e}")
-                    raise
-                except OSError as e:
-                    _LOGGER.error(f"OS error reading history file: {e}")
-                    raise
-
-            history.append(entry)
-
-            if len(history) > self.max_history_size:
-                history = history[-self.max_history_size:]
-
-            # Write with atomic operation
-            temp_file = f"{self._history_file}.tmp"
-            try:
-                with open(temp_file, 'w', encoding='utf-8') as f:
-                    json.dump(history, f, indent=2, ensure_ascii=False)
-                os.replace(temp_file, self._history_file)
-            except PermissionError as e:
-                _LOGGER.error(f"Permission denied writing history file: {e}")
-                raise
-            except OSError as e:
-                _LOGGER.error(f"OS error writing history file: {e}")
-                # Clean up temp file if it exists
-                try:
-                    os.remove(temp_file)
-                except OSError:
-                    pass
-                raise
-
-        except Exception as e:
-            _LOGGER.error(f"Synchronous history entry writing failed: {e}")
-            raise
-
     async def _rotate_history(self) -> None:
         """Rotate conversation history with file management."""
         try:
-            _LOGGER.debug(f"Starting history rotation for {self._history_file}")
-            await self.hass.async_add_executor_job(self._rotate_history_files)
-            _LOGGER.debug(f"Completed history rotation")
+            _LOGGER.debug("Starting history rotation for %s", self._history_file)
+            await self._rotate_history_files()
+            _LOGGER.debug("Completed history rotation")
         except Exception as e:
-            _LOGGER.error(f"Error rotating history: {e}")
+            _LOGGER.error("Error rotating history: %s", e)
             _LOGGER.debug(traceback.format_exc())
 
     async def _check_history_directory(self) -> None:
@@ -639,9 +587,10 @@ class HATextAICoordinator(DataUpdateCoordinator):
                         f"{self.normalized_name}_history_{dt_util.utcnow().strftime('%Y%m%d_%H%M%S')}.json"
                     )
 
-                    # Rotate files
+                    # Rotate files (shutil.move for cross-device safety)
+                    import shutil
                     await self.hass.async_add_executor_job(
-                        os.rename,
+                        shutil.move,
                         self._history_file,
                         archive_file
                     )
@@ -662,37 +611,36 @@ class HATextAICoordinator(DataUpdateCoordinator):
     async def _async_update_data(self) -> Dict[str, Any]:
         """Update coordinator data with improved error handling and performance."""
         try:
-            async with asyncio.Semaphore(1):
-                current_state = self._get_current_state()
+            current_state = self._get_current_state()
 
-                # Get limited history with info
-                history_data = await self._get_limited_history()
+            # Get limited history with info
+            history_data = await self._get_limited_history()
 
-                metrics = await self._get_current_metrics()
-                if metrics is None:
-                    metrics = {}
+            metrics = await self._get_current_metrics()
+            if metrics is None:
+                metrics = {}
 
-                data = {
-                    "state": current_state,
-                    "metrics": metrics,
-                    "last_response": await self._get_sanitized_last_response(),
-                    "is_processing": self._is_processing,
-                    "is_rate_limited": self._is_rate_limited,
-                    "is_maintenance": self._is_maintenance,
-                    "endpoint_status": self.endpoint_status,
-                    "uptime": self._calculate_uptime(),
-                    "system_prompt": self._get_truncated_system_prompt(),
-                    "history_size": len(self._conversation_history),
-                    "conversation_history": history_data["entries"],
-                    "history_info": history_data["info"],
-                    "normalized_name": self.normalized_name,
-                }
+            data = {
+                "state": current_state,
+                "metrics": metrics,
+                "last_response": await self._get_sanitized_last_response(),
+                "is_processing": self._is_processing,
+                "is_rate_limited": self._is_rate_limited,
+                "is_maintenance": self._is_maintenance,
+                "endpoint_status": self.endpoint_status,
+                "uptime": self._calculate_uptime(),
+                "system_prompt": self._get_truncated_system_prompt(),
+                "history_size": len(self._conversation_history),
+                "conversation_history": history_data["entries"],
+                "history_info": history_data["info"],
+                "normalized_name": self.normalized_name,
+            }
 
-                await self._validate_update_data(data)
-                return data
+            await self._validate_update_data(data)
+            return data
 
         except Exception as err:
-            _LOGGER.error(f"Error updating data: {err}", exc_info=True)
+            _LOGGER.error("Error updating data: %s", err, exc_info=True)
             return self._get_safe_initial_state()
 
     async def _get_limited_history(self) -> Dict[str, Any]:
@@ -712,7 +660,6 @@ class HATextAICoordinator(DataUpdateCoordinator):
             "total_entries": len(self._conversation_history),
             "displayed_entries": len(limited_history),
             "full_history_available": True,
-            "history_path": self._history_file,
         }
 
         return {
@@ -764,21 +711,14 @@ class HATextAICoordinator(DataUpdateCoordinator):
             raise ValueError("Invalid metrics format")
 
     async def async_update_ha_state(self) -> None:
-        """Update Home Assistant state."""
+        """Update Home Assistant state via coordinator refresh."""
         try:
             _LOGGER.debug(
-                f"Requesting state update for {self.instance_name} (normalized: {self.normalized_name})"
+                "Requesting state update for %s", self.instance_name,
             )
             await self.async_request_refresh()
-
-            # Force update of all entities
-            entity_id_base = f"sensor.ha_text_ai_{self.normalized_name.lower()}"
-            for entity_id in self.hass.states.async_entity_ids():
-                if entity_id.startswith(entity_id_base):
-                    self.hass.states.async_set(entity_id, self._get_current_state())
-
         except Exception as err:
-            _LOGGER.error(f"Error updating HA state for {self.instance_name}: {err}")
+            _LOGGER.error("Error updating HA state for %s: %s", self.instance_name, err)
 
     def _get_current_state(self) -> str:
         """Get current state based on internal flags."""
@@ -860,61 +800,56 @@ class HATextAICoordinator(DataUpdateCoordinator):
             if self.client is None:
                 raise HomeAssistantError("AI client not initialized")
 
-            try:
-                self._is_processing = True
-                await self.async_update_ha_state()
+            async with self._request_lock:
+                try:
+                    self._is_processing = True
+                    await self.async_update_ha_state()
 
-                temp_context_messages = context_messages or self.context_messages
-                temp_model = model or self.model
-                temp_temperature = temperature or self.temperature
-                temp_max_tokens = max_tokens or self.max_tokens
-                temp_system_prompt = system_prompt or self._system_prompt
+                    temp_context_messages = context_messages if context_messages is not None else self.context_messages
+                    temp_model = model if model is not None else self.model
+                    temp_temperature = temperature if temperature is not None else self.temperature
+                    temp_max_tokens = max_tokens if max_tokens is not None else self.max_tokens
+                    temp_system_prompt = system_prompt if system_prompt is not None else self._system_prompt
 
-                # Start timing
-                start_time = dt_util.utcnow()
+                    start_time = dt_util.utcnow()
 
-                # Prepare messages with system prompt
-                messages = []
-                if temp_system_prompt:
-                    messages.append({"role": "system", "content": temp_system_prompt})
+                    messages = []
+                    if temp_system_prompt:
+                        messages.append({"role": "system", "content": temp_system_prompt})
 
-                # Add context from history
-                context_history = self._conversation_history[-temp_context_messages:]
-                for entry in context_history:
-                    messages.append({"role": "user", "content": entry["question"]})
-                    messages.append({"role": "assistant", "content": entry["response"]})
+                    context_history = self._conversation_history[-temp_context_messages:]
+                    for entry in context_history:
+                        messages.append({"role": "user", "content": entry["question"]})
+                        messages.append({"role": "assistant", "content": entry["response"]})
 
-                # Add current question
-                messages.append({"role": "user", "content": question})
+                    messages.append({"role": "user", "content": question})
 
-                # Process message
-                kwargs = {
-                    "model": temp_model,
-                    "temperature": temp_temperature,
-                    "max_tokens": temp_max_tokens,
-                    "messages": messages,
-                    "structured_output": structured_output,
-                    "json_schema": json_schema,
-                }
+                    kwargs = {
+                        "model": temp_model,
+                        "temperature": temp_temperature,
+                        "max_tokens": temp_max_tokens,
+                        "messages": messages,
+                        "structured_output": structured_output,
+                        "json_schema": json_schema,
+                    }
 
-                response = await self.async_process_message(question, **kwargs)
+                    response = await self.async_process_message(question, **kwargs)
 
-                # Update metrics
-                end_time = dt_util.utcnow()
-                latency = (end_time - start_time).total_seconds()
-                await self._update_metrics(latency, response)
+                    end_time = dt_util.utcnow()
+                    latency = (end_time - start_time).total_seconds()
+                    await self._update_metrics(latency, response)
 
-                await self._update_history(question, response)
+                    await self._update_history(question, response)
 
-                return response
+                    return response
 
-            except Exception as err:
-                await self._handle_error(err)
-                raise HomeAssistantError(f"Failed to process question: {err}")
+                except Exception as err:
+                    await self._handle_error(err)
+                    raise HomeAssistantError(f"Failed to process question: {err}")
 
-            finally:
-                self._is_processing = False
-                await self.async_update_ha_state()
+                finally:
+                    self._is_processing = False
+                    await self.async_update_ha_state()
 
     async def async_process_message(self, question: str, **kwargs) -> dict:
         """Process message using the AI client."""
@@ -929,6 +864,10 @@ class HATextAICoordinator(DataUpdateCoordinator):
                     json_schema=json_schema, **kwargs
                 )
 
+            # Reset error state on success
+            self._is_rate_limited = False
+            self.endpoint_status = "ready"
+
             # Add timestamp and model information to response
             timestamp = dt_util.utcnow().isoformat()
             model_used = kwargs.get("model", self.model)
@@ -1039,9 +978,10 @@ class HATextAICoordinator(DataUpdateCoordinator):
                 async with AsyncFileHandler(self._history_file, 'w') as f:
                     await f.write(json.dumps(history_entries, indent=2))
 
-                # Backup old file
+                # Backup old file (use shutil.move for cross-device safety)
+                import shutil
                 backup_file = old_history_file + '.backup'
-                os.rename(old_history_file, backup_file)
+                await self.hass.async_add_executor_job(shutil.move, old_history_file, backup_file)
 
                 _LOGGER.info(
                     f"Successfully migrated {len(history_entries)} entries "
@@ -1132,25 +1072,6 @@ class HATextAICoordinator(DataUpdateCoordinator):
         self._system_prompt = prompt
         await self.async_update_ha_state()
 
-    def _check_memory_available(self) -> bool:
-        """Check if enough memory is available."""
-        try:
-            memory = psutil.virtual_memory()
-            
-            # Log the total and available memory
-            _LOGGER.debug("Total memory: %s, Available memory: %s", memory.total, memory.available)
-            
-            if memory.available > 1024 * 1024 * 100:  # 100MB
-                _LOGGER.debug("Sufficient memory available: %s bytes", memory.available)
-                return True
-            else:
-                _LOGGER.warning("Insufficient memory available: %s bytes", memory.available)
-                return False
-        except Exception as e:
-            _LOGGER.error("Error checking memory availability: %s", e)
-            return True  # Assume memory is available if check fails
-
     async def async_shutdown(self) -> None:
         """Shutdown coordinator."""
-        _LOGGER.debug(f"Shutting down coordinator for {self.instance_name}")
-        self.hass.data[DOMAIN].pop(self.instance_name, None)
+        _LOGGER.debug("Shutting down coordinator for %s", self.instance_name)
diff --git a/custom_components/ha_text_ai/manifest.json b/custom_components/ha_text_ai/manifest.json
index 80fcb39..0ead9ea 100644
--- a/custom_components/ha_text_ai/manifest.json
+++ b/custom_components/ha_text_ai/manifest.json
@@ -2,7 +2,6 @@
   "domain": "ha_text_ai",
   "name": "HA Text AI",
   "after_dependencies": ["http"],
-  "bluetooth": [],
   "codeowners": ["@smkrv"],
   "config_flow": true,
   "dependencies": [],
@@ -11,20 +10,10 @@
   "iot_class": "cloud_polling",
   "issue_tracker": "https://github.com/smkrv/ha-text-ai/issues",
   "loggers": ["custom_components.ha_text_ai"],
-  "mqtt": [],
-  "quality_scale": "silver",
   "requirements": [
     "aiofiles>=23.0.0",
-    "aiohttp>=3.8.0",
-    "anthropic>=0.8.0",
-    "async-timeout>=4.0.0",
-    "certifi>=2024.2.2",
-    "google-genai>=1.16.0",
-    "openai>=1.12.0"
+    "aiohttp>=3.8.0"
   ],
   "single_config_entry": false,
-  "ssdp": [],
-  "usb": [],
-  "version": "2.3.0",
-  "zeroconf": []
+  "version": "2.4.0"
 }
diff --git a/custom_components/ha_text_ai/sensor.py b/custom_components/ha_text_ai/sensor.py
index 2e7a023..31b4d67 100644
--- a/custom_components/ha_text_ai/sensor.py
+++ b/custom_components/ha_text_ai/sensor.py
@@ -73,6 +73,7 @@ from .const import (
 )
 
 from .coordinator import HATextAICoordinator
+from .utils import safe_log_data
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -83,23 +84,23 @@ async def async_setup_entry(
     async_add_entities: AddEntitiesCallback,
 ) -> None:
     """Set up the HA Text AI sensor."""
-    _LOGGER.debug(f"Starting sensor setup for entry: {entry.entry_id}")
+    _LOGGER.debug("Starting sensor setup for entry: %s", entry.entry_id)
 
     try:
         coordinator = hass.data[DOMAIN][entry.entry_id]
-        _LOGGER.debug(f"Found coordinator for entry {entry.entry_id}")
+        _LOGGER.debug("Found coordinator for entry %s", entry.entry_id)
 
         instance_name = coordinator.instance_name
-        _LOGGER.debug(f"Setting up sensor with instance: {instance_name}")
+        _LOGGER.debug("Setting up sensor with instance: %s", instance_name)
 
         sensor = HATextAISensor(coordinator, entry)
-        _LOGGER.debug(f"Created sensor instance: {sensor.entity_id}")
+        _LOGGER.debug("Created sensor instance: %s", sensor.entity_id)
 
         async_add_entities([sensor], True)
-        _LOGGER.debug(f"Added sensor entity: {sensor.entity_id}")
+        _LOGGER.debug("Added sensor entity: %s", sensor.entity_id)
 
     except Exception as err:
-        _LOGGER.exception(f"Error setting up sensor: {err}")
+        _LOGGER.exception("Error setting up sensor: %s", err)
         raise
 
 class HATextAISensor(CoordinatorEntity, SensorEntity):
@@ -113,7 +114,7 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         config_entry: ConfigEntry,
     ) -> None:
         """Initialize the sensor."""
-        _LOGGER.debug(f"Initializing sensor with config entry: {config_entry.data}")
+        _LOGGER.debug("Initializing sensor with config entry: %s", safe_log_data(dict(config_entry.data)))
 
         super().__init__(coordinator)
 
@@ -121,8 +122,8 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         self._instance_name = coordinator.instance_name
         self._normalized_name = coordinator.normalized_name
 
-        _LOGGER.debug(f"Instance name: {self._instance_name}")
-        _LOGGER.debug(f"Normalized name: {self._normalized_name}")
+        _LOGGER.debug("Instance name: %s", self._instance_name)
+        _LOGGER.debug("Normalized name: %s", self._normalized_name)
 
         self._conversation_history = []
         self._system_prompt = None
@@ -131,9 +132,9 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         self.entity_id = f"sensor.ha_text_ai_{self._normalized_name}"
         self._attr_unique_id = f"{config_entry.entry_id}"
 
-        _LOGGER.debug(f"Created sensor with entity_id: {self.entity_id}")
-        _LOGGER.debug(f"Sensor name: {self._attr_name}")
-        _LOGGER.debug(f"Unique ID: {self._attr_unique_id}")
+        _LOGGER.debug("Created sensor with entity_id: %s", self.entity_id)
+        _LOGGER.debug("Sensor name: %s", self._attr_name)
+        _LOGGER.debug("Unique ID: %s", self._attr_unique_id)
 
         self.entity_description = SensorEntityDescription(
             key=f"ha_text_ai_{self._normalized_name.lower()}",
@@ -160,7 +161,8 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         )
 
         _LOGGER.debug(
-            f"Initialized sensor: {self.entity_id} for instance: {self._instance_name}"
+            "Initialized sensor: %s for instance: %s",
+            self.entity_id, self._instance_name,
         )
 
     @property
@@ -200,7 +202,7 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         ]
 
         metrics_values = {k: sanitized.get(k) for k in metrics_keys if k in sanitized}
-        _LOGGER.debug(f"Metrics for {self.entity_id}: {metrics_values}")
+        _LOGGER.debug("Metrics for %s: %s", self.entity_id, metrics_values)
 
         return sanitized
 
@@ -302,7 +304,7 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
         """When entity is added to hass."""
         await super().async_added_to_hass()
         self._handle_coordinator_update()
-        _LOGGER.debug(f"Entity {self.entity_id} added to Home Assistant")
+        _LOGGER.debug("Entity %s added to Home Assistant", self.entity_id)
 
     def _handle_coordinator_update(self) -> None:
         """Handle updated data from the coordinator."""
@@ -310,7 +312,7 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
             data = self.coordinator.data
             if not self.coordinator.last_update_success or not data:
                 self._current_state = STATE_DISCONNECTED
-                _LOGGER.warning(f"No data available for {self.entity_id}")
+                _LOGGER.warning("No data available for %s", self.entity_id)
                 self.async_write_ha_state()
                 return
 
@@ -320,7 +322,7 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
             metrics = data.get("metrics", {})
             if isinstance(metrics, dict):
                 self._metrics.update(metrics)
-                _LOGGER.debug(f"Updated metrics for {self.entity_id}: {self._metrics}")
+                _LOGGER.debug("Updated metrics for %s: %s", self.entity_id, self._metrics)
 
             # Update conversation history and system prompt
             self._conversation_history = data.get("conversation_history", [])
@@ -344,8 +346,8 @@ class HATextAISensor(CoordinatorEntity, SensorEntity):
             self._last_update = dt_util.utcnow()
 
             _LOGGER.debug(
-                f"Updated {self.entity_id} state to: {self._current_state} "
-                f"(available: {self.available})"
+                "Updated %s state to: %s (available: %s)",
+                self.entity_id, self._current_state, self.available,
             )
 
         except Exception as err:
diff --git a/custom_components/ha_text_ai/strings.json b/custom_components/ha_text_ai/strings.json
new file mode 100644
index 0000000..ff62875
--- /dev/null
+++ b/custom_components/ha_text_ai/strings.json
@@ -0,0 +1,309 @@
+{
+  "config": {
+    "step": {
+      "provider": {
+        "title": "Provider Settings",
+        "description": "Provide connection details for your chosen AI provider.",
+        "data": {
+          "name": "Instance name (e.g., 'GPT Assistant', 'Claude Helper')",
+          "api_key": "API key for authentication",
+          "model": "AI model to use",
+          "api_endpoint": "Custom API endpoint URL (optional)",
+          "temperature": "Response creativity (0-2, lower = more focused)",
+          "max_tokens": "Maximum response length (1-100000 tokens)",
+          "request_interval": "Minimum time between requests (0.1-60 seconds)",
+          "api_timeout": "API request timeout in seconds (5-600)",
+          "context_messages": "Number of context messages to retain (1-20)",
+          "max_history_size": "Maximum conversation history size (1-100)"
+        }
+      },
+      "user": {
+        "title": "Configure HA Text AI Instance",
+        "description": "Set up a new AI assistant instance with your selected provider.",
+        "data": {
+          "name": "Instance name (e.g., 'GPT Assistant', 'Claude Helper')",
+          "api_key": "API key for authentication",
+          "model": "AI model to use",
+          "temperature": "Response creativity (0-2, lower = more focused)",
+          "max_tokens": "Maximum response length (1-100000 tokens)",
+          "api_endpoint": "Custom API endpoint URL (optional)",
+          "api_provider": "API Provider",
+          "request_interval": "Minimum time between requests (0.1-60 seconds)",
+          "api_timeout": "API request timeout in seconds (5-600)",
+          "context_messages": "Number of context messages to retain (1-20)",
+          "max_history_size": "Maximum conversation history size (1-100)"
+        }
+      }
+    },
+    "error": {
+      "history_storage_error": "Failed to initialize history storage. Check permissions.",
+      "history_rotation_error": "Error during history file rotation.",
+      "history_file_access_error": "Cannot access history storage directory.",
+      "name_exists": "An instance with this name already exists",
+      "invalid_name": "Invalid instance name",
+      "invalid_auth": "Authentication failed - check your API key",
+      "invalid_api_key": "Invalid API key - please verify your credentials",
+      "cannot_connect": "Failed to connect to API service",
+      "invalid_model": "Selected model is not available",
+      "rate_limit": "Rate limit exceeded",
+      "context_length": "Context length exceeded",
+      "rate_limit_exceeded": "API rate limit exceeded",
+      "maintenance": "Service is under maintenance",
+      "invalid_response": "Invalid API response received",
+      "api_error": "API service error occurred",
+      "timeout": "Request timed out",
+      "invalid_instance": "Invalid instance specified",
+      "unknown": "Unexpected error occurred",
+      "empty": "Name cannot be empty",
+      "invalid_characters": "Name can only contain letters, numbers, spaces, underscores and hyphens",
+      "name_too_long": "Name must be 50 characters or less"
+    },
+    "abort": {
+      "already_configured": "Instance already configured"
+    }
+  },
+  "options": {
+    "step": {
+      "init": {
+        "title": "Select Provider",
+        "description": "Choose the AI provider for this instance. The integration will reload after saving changes.",
+        "data": {
+          "api_provider": "API Provider"
+        }
+      },
+      "settings": {
+        "title": "Connection & Model Settings",
+        "description": "Configure API credentials and model parameters. Changes will take effect after the integration reloads.",
+        "data": {
+          "api_key": "API Key",
+          "api_endpoint": "API Endpoint URL",
+          "model": "AI model",
+          "temperature": "Response creativity (0-2)",
+          "max_tokens": "Maximum response length (1-100000)",
+          "request_interval": "Minimum request interval (0.1-60 seconds)",
+          "api_timeout": "API request timeout in seconds (5-600)",
+          "context_messages": "Number of previous messages to include in context (1-20)",
+          "max_history_size": "Maximum conversation history size (1-100)"
+        }
+      }
+    }
+  },
+  "selector": {
+    "api_provider": {
+      "options": {
+        "openai": "OpenAI (compatible)",
+        "anthropic": "Anthropic (compatible)",
+        "deepseek": "DeepSeek",
+        "gemini": "Google Gemini"
+      }
+    }
+  },
+  "services": {
+    "ask_question": {
+      "name": "Ask Question (HA Text AI)",
+      "description": "Send a question to the AI model and receive a detailed response. This service now returns response data directly, eliminating the need for separate text sensors and the 255-character limitation. The response will also be stored in the conversation history.",
+      "fields": {
+        "instance": {
+          "name": "Instance",
+          "description": "Name of the HA Text AI instance to use"
+        },
+        "question": {
+          "name": "Question",
+          "description": "Your question or prompt for the AI assistant"
+        },
+        "context_messages": {
+          "name": "Context Messages",
+          "description": "Number of previous messages to include in context (1-20)"
+        },
+        "system_prompt": {
+          "name": "System Prompt",
+          "description": "Optional system prompt to set context for this specific question"
+        },
+        "model": {
+          "name": "Model",
+          "description": "Select AI model to use (optional, overrides default setting)"
+        },
+        "temperature": {
+          "name": "Temperature",
+          "description": "Controls response creativity (0.0-2.0)"
+        },
+        "max_tokens": {
+          "name": "Max Tokens",
+          "description": "Maximum length of the response (1-100000 tokens)"
+        },
+        "structured_output": {
+          "name": "Structured Output",
+          "description": "Enable JSON structured output mode. When enabled, the AI will respond with valid JSON matching the provided schema."
+        },
+        "json_schema": {
+          "name": "JSON Schema",
+          "description": "JSON Schema defining the structure of the expected response. Required when structured_output is enabled."
+        }
+      }
+    },
+    "clear_history": {
+      "name": "Clear History",
+      "description": "Delete all stored questions and responses from the conversation history",
+      "fields": {
+        "instance": {
+          "name": "Instance",
+          "description": "Name of the HA Text AI instance to clear history for"
+        }
+      }
+    },
+    "get_history": {
+      "name": "Get History",
+      "description": "Retrieve conversation history with optional filtering and sorting",
+      "fields": {
+        "instance": {
+          "name": "Instance",
+          "description": "Name of the HA Text AI instance to get history from"
+        },
+        "limit": {
+          "name": "Limit",
+          "description": "Number of conversations to return (1-100)"
+        },
+        "filter_model": {
+          "name": "Filter Model",
+          "description": "Filter conversations by specific AI model"
+        },
+        "start_date": {
+          "name": "Start Date",
+          "description": "Filter conversations starting from this date/time"
+        },
+        "include_metadata": {
+          "name": "Include Metadata",
+          "description": "Include additional information like tokens used, response time, etc."
+        },
+        "sort_order": {
+          "name": "Sort Order",
+          "description": "Sort order for results (newest or oldest first)"
+        }
+      }
+    },
+    "set_system_prompt": {
+      "name": "Set System Prompt",
+      "description": "Set default system behavior instructions for all future conversations",
+      "fields": {
+        "instance": {
+          "name": "Instance",
+          "description": "Name of the HA Text AI instance to set system prompt for"
+        },
+        "prompt": {
+          "name": "System Prompt",
+          "description": "Instructions that define how the AI should behave and respond"
+        }
+      }
+    }
+  },
+  "entity": {
+    "sensor": {
+      "ha_text_ai": {
+        "name": "{name}",
+        "state": {
+          "ready": "Ready",
+          "processing": "Processing",
+          "error": "Error",
+          "disconnected": "Disconnected",
+          "rate_limited": "Rate Limited",
+          "maintenance": "Maintenance",
+          "initializing": "Initializing",
+          "retrying": "Retrying",
+          "queued": "Queued"
+        },
+        "state_attributes": {
+          "question": {
+            "name": "Last Question"
+          },
+          "response": {
+            "name": "Last Response"
+          },
+          "model": {
+            "name": "Current Model"
+          },
+          "temperature": {
+            "name": "Temperature"
+          },
+          "max_tokens": {
+            "name": "Max Tokens"
+          },
+          "system_prompt": {
+            "name": "System Prompt"
+          },
+          "response_time": {
+            "name": "Last Response Time"
+          },
+          "total_responses": {
+            "name": "Total Responses"
+          },
+          "error_count": {
+            "name": "Error Count"
+          },
+          "last_error": {
+            "name": "Last Error"
+          },
+          "api_status": {
+            "name": "API Status"
+          },
+          "tokens_used": {
+            "name": "Total Tokens Used"
+          },
+          "average_response_time": {
+            "name": "Average Response Time"
+          },
+          "last_request_time": {
+            "name": "Last Request Time"
+          },
+          "is_processing": {
+            "name": "Processing Status"
+          },
+          "is_rate_limited": {
+            "name": "Rate Limited Status"
+          },
+          "is_maintenance": {
+            "name": "Maintenance Status"
+          },
+          "api_version": {
+            "name": "API Version"
+          },
+          "endpoint_status": {
+            "name": "Endpoint Status"
+          },
+          "performance_metrics": {
+            "name": "Performance Metrics"
+          },
+          "history_size": {
+            "name": "History Size"
+          },
+          "uptime": {
+            "name": "Uptime"
+          },
+          "total_tokens": {
+            "name": "Total Tokens"
+          },
+          "prompt_tokens": {
+            "name": "Prompt Tokens"
+          },
+          "completion_tokens": {
+            "name": "Completion Tokens"
+          },
+          "successful_requests": {
+            "name": "Successful Requests"
+          },
+          "failed_requests": {
+            "name": "Failed Requests"
+          },
+          "average_latency": {
+            "name": "Average Latency"
+          },
+          "max_latency": {
+            "name": "Maximum Latency"
+          },
+          "min_latency": {
+            "name": "Minimum Latency"
+          }
+        }
+      }
+    }
+  }
+}
diff --git a/custom_components/ha_text_ai/translations/de.json b/custom_components/ha_text_ai/translations/de.json
index 1061de9..96d6d44 100644
--- a/custom_components/ha_text_ai/translations/de.json
+++ b/custom_components/ha_text_ai/translations/de.json
@@ -1,15 +1,6 @@
 {
   "config": {
     "step": {
-      "provider": {
-        "title": "Wählen Sie AI-Anbieter",
-        "description": "Wählen Sie, welchen AI-Dienstanbieter Sie für diese Instanz verwenden möchten.",
-        "data": {
-          "api_provider": "API-Anbieter",
-          "context_messages": "Anzahl der zu behaltenden Kontextnachrichten (1-20)",
-          "max_history_size": "Maximale Größe des Gesprächsverlaufs (1-100)"
-        }
-      },
       "provider": {
         "title": "Anbieter-Einstellungen",
         "description": "Geben Sie die Verbindungsdetails für Ihren gewählten AI-Anbieter an.",
diff --git a/custom_components/ha_text_ai/translations/en.json b/custom_components/ha_text_ai/translations/en.json
index b3b6187..ff62875 100644
--- a/custom_components/ha_text_ai/translations/en.json
+++ b/custom_components/ha_text_ai/translations/en.json
@@ -1,15 +1,6 @@
 {
   "config": {
     "step": {
-      "provider": {
-        "title": "Select AI Provider",
-        "description": "Choose which AI service provider to use for this instance.",
-        "data": {
-          "api_provider": "API Provider",
-          "context_messages": "Number of context messages to retain (1-20)",
-          "max_history_size": "Maximum conversation history size (1-100)"
-        }
-      },
       "provider": {
         "title": "Provider Settings",
         "description": "Provide connection details for your chosen AI provider.",
diff --git a/custom_components/ha_text_ai/translations/es.json b/custom_components/ha_text_ai/translations/es.json
index f33de77..86d3323 100644
--- a/custom_components/ha_text_ai/translations/es.json
+++ b/custom_components/ha_text_ai/translations/es.json
@@ -1,15 +1,6 @@
 {
   "config": {
     "step": {
-      "provider": {
-        "title": "Seleccionar proveedor de IA",
-        "description": "Elige qué proveedor de servicio de IA utilizar para esta instancia.",
-        "data": {
-          "api_provider": "Proveedor de API",
-          "context_messages": "Número de mensajes de contexto a retener (1-20)",
-          "max_history_size": "Tamaño máximo del historial de conversación (1-100)"
-        }
-      },
       "provider": {
         "title": "Configuración del proveedor",
         "description": "Proporciona los detalles de conexión para tu proveedor de IA elegido.",
diff --git a/custom_components/ha_text_ai/translations/it.json b/custom_components/ha_text_ai/translations/it.json
index 087563a..c4cbeca 100644
--- a/custom_components/ha_text_ai/translations/it.json
+++ b/custom_components/ha_text_ai/translations/it.json
@@ -1,15 +1,6 @@
 {
   "config": {
     "step": {
-      "provider": {
-        "title": "Seleziona fornitore AI",
-        "description": "Scegli quale fornitore di servizi AI utilizzare per questa istanza.",
-        "data": {
-          "api_provider": "Fornitore API",
-          "context_messages": "Numero di messaggi di contesto da mantenere (1-20)",
-          "max_history_size": "Dimensione massima della cronologia delle conversazioni (1-100)"
-        }
-      },
       "provider": {
         "title": "Impostazioni fornitore",
         "description": "Fornisci i dettagli di connessione per il tuo fornitore di AI scelto.",
diff --git a/custom_components/ha_text_ai/translations/ru.json b/custom_components/ha_text_ai/translations/ru.json
index 35882fe..aa48c64 100644
--- a/custom_components/ha_text_ai/translations/ru.json
+++ b/custom_components/ha_text_ai/translations/ru.json
@@ -1,15 +1,6 @@
 {
   "config": {
     "step": {
-      "provider": {
-        "title": "Выбор провайдера ИИ",
-        "description": "Выберите сервис искусственного интеллекта для этого экземпляра.",
-        "data": {
-          "api_provider": "Провайдер API",
-          "context_messages": "Количество сохраняемых контекстных сообщений (1-20)",
-          "max_history_size": "Максимальный размер истории разговора (1-100)"
-        }
-      },
       "provider": {
         "title": "Настройки провайдера",
         "description": "Укажите параметры подключения для выбранного провайдера ИИ.",
diff --git a/custom_components/ha_text_ai/translations/sr.json b/custom_components/ha_text_ai/translations/sr.json
index a3d2d59..aa7397d 100644
--- a/custom_components/ha_text_ai/translations/sr.json
+++ b/custom_components/ha_text_ai/translations/sr.json
@@ -204,7 +204,7 @@
           "ready": "Спремно",
           "processing": "Обрада",
           "error": "Грешка",
-          "disconnected": "Прекључено",
+          "disconnected": "Искључено",
           "rate_limited": "Ограничење захтева",
           "maintenance": "Одржавање",
           "initializing": "Инициализује се",
diff --git a/custom_components/ha_text_ai/utils.py b/custom_components/ha_text_ai/utils.py
index 41adcfe..66331b3 100644
--- a/custom_components/ha_text_ai/utils.py
+++ b/custom_components/ha_text_ai/utils.py
@@ -6,8 +6,9 @@ Utility functions for HA Text AI integration.
 @github: https://github.com/smkrv/ha-text-ai
 @source: https://github.com/smkrv/ha-text-ai
 """
-import hashlib
+import ipaddress
 from typing import Any
+from urllib.parse import urlparse
 
 from homeassistant.const import CONF_API_KEY
 
@@ -19,18 +20,41 @@ def normalize_name(name: str) -> str:
     return normalized.lower()
 
 
-def get_file_hash(file_path: str) -> str:
-    """Calculate SHA256 hash of file."""
-    sha256_hash = hashlib.sha256()
-    with open(file_path, "rb") as f:
-        for byte_block in iter(lambda: f.read(4096), b""):
-            sha256_hash.update(byte_block)
-    return sha256_hash.hexdigest()
-
-
 def safe_log_data(
     data: dict[str, Any],
     sensitive_keys: tuple[str, ...] = (CONF_API_KEY,),
 ) -> dict[str, Any]:
     """Filter sensitive keys from data for safe logging."""
     return {k: "***" if k in sensitive_keys else v for k, v in data.items()}
+
+
+
+def validate_endpoint(endpoint: str) -> str:
+    """Validate API endpoint URL for security.
+
+    Ensures HTTPS-only and blocks private/reserved IP ranges (SSRF protection).
+    Returns the validated endpoint stripped of trailing slashes.
+
+    Raises:
+        ValueError: If the endpoint fails validation.
+    """
+    parsed = urlparse(endpoint)
+
+    if parsed.scheme not in ("https",):
+        raise ValueError("Only HTTPS endpoints are allowed")
+
+    hostname = parsed.hostname
+    if not hostname:
+        raise ValueError("Invalid endpoint URL: no hostname")
+
+    # Block private/reserved IPs
+    try:
+        addr = ipaddress.ip_address(hostname)
+        if addr.is_private or addr.is_reserved or addr.is_loopback or addr.is_link_local:
+            raise ValueError("Private/reserved IP addresses are not allowed")
+    except ValueError as e:
+        if "not allowed" in str(e):
+            raise
+        # Not an IP address — it's a hostname, which is fine
+
+    return endpoint.rstrip("/")