diff --git a/api/routes.py b/api/routes.py
index 900848c1..b2c9453a 100644
--- a/api/routes.py
+++ b/api/routes.py
@@ -1,6 +1,5 @@
 """FastAPI route handlers."""
 
-import json
 import logging
 import uuid
 
diff --git a/cli/parser.py b/cli/parser.py
index 1619acbe..a3b215aa 100644
--- a/cli/parser.py
+++ b/cli/parser.py
@@ -1,7 +1,7 @@
 """CLI event parser for Claude Code CLI output."""
 
 import logging
-from typing import Dict, List, Optional
+from typing import Dict, List
 
 logger = logging.getLogger(__name__)
 
diff --git a/cli/session.py b/cli/session.py
index cb1d21d0..99746a02 100644
--- a/cli/session.py
+++ b/cli/session.py
@@ -84,7 +84,7 @@ class CLISession:
                     "--dangerously-skip-permissions",
                     "--verbose",
                 ]
-                logger.info(f"Starting new Claude session")
+                logger.info("Starting new Claude session")
 
             if self.allowed_dirs:
                 for d in self.allowed_dirs:
@@ -149,7 +149,7 @@ class CLISession:
                         logger.error(f"Claude CLI Stderr: {stderr_text}")
                         # Yield stderr as error event so it shows in UI
                         if stderr_text:
-                            logger.info(f"CLI_SESSION: Yielding error event from stderr")
+                            logger.info("CLI_SESSION: Yielding error event from stderr")
                             yield {"type": "error", "error": {"message": stderr_text}}
 
                 return_code = await self.process.wait()
diff --git a/messaging/base.py b/messaging/base.py
index 0981c0b2..4517d6b8 100644
--- a/messaging/base.py
+++ b/messaging/base.py
@@ -1,7 +1,7 @@
 """Abstract base class for messaging platforms."""
 
 from abc import ABC, abstractmethod
-from typing import Callable, Awaitable, Optional, Any, Protocol, Tuple, runtime_checkable
+from typing import Callable, Awaitable, Optional, Protocol, Tuple, runtime_checkable
 from .models import IncomingMessage
 
 
diff --git a/messaging/handler.py b/messaging/handler.py
index 3bd7908e..d7b2c500 100644
--- a/messaging/handler.py
+++ b/messaging/handler.py
@@ -11,7 +11,7 @@ import asyncio
 import logging
 from typing import Optional, TYPE_CHECKING
 
-from .base import MessagingPlatform, SessionManagerInterface, CLISession
+from .base import MessagingPlatform, SessionManagerInterface
 from .models import IncomingMessage
 from .session import SessionStore
 from .tree_queue import TreeQueueManager, MessageNode, MessageState
@@ -279,7 +279,7 @@ class ClaudeMessageHandler:
                     elif parsed["type"] == "complete":
                         if not any(components.values()):
                             components["content"].append("Done.")
-                        logger.info(f"HANDLER: Task complete, updating UI")
+                        logger.info("HANDLER: Task complete, updating UI")
                         # Always force final complete status to bypass flood wait
                         await update_ui("✅ **Complete**", force=True)
 
@@ -298,7 +298,7 @@ class ClaudeMessageHandler:
                             f"HANDLER: Error event received: {error_msg[:200]}"
                         )
                         components["errors"].append(error_msg)
-                        logger.info(f"HANDLER: Updating UI with error status")
+                        logger.info("HANDLER: Updating UI with error status")
                         # Always force error status to bypass flood wait
                         await update_ui("❌ **Error**", force=True)
                         if tree:
@@ -313,7 +313,7 @@ class ClaudeMessageHandler:
                                     self.platform.queue_edit_message(
                                         child.incoming.chat_id,
                                         child.status_message_id,
-                                        f"❌ **Cancelled:** Parent task failed",
+                                        "❌ **Cancelled:** Parent task failed",
                                         parse_mode="markdown",
                                     )
                                 )
@@ -335,7 +335,7 @@ class ClaudeMessageHandler:
                         self.platform.queue_edit_message(
                             child.incoming.chat_id,
                             child.status_message_id,
-                            f"❌ **Cancelled:** Parent task was stopped",
+                            "❌ **Cancelled:** Parent task was stopped",
                             parse_mode="markdown",
                         )
                     )
@@ -359,7 +359,7 @@ class ClaudeMessageHandler:
                         self.platform.queue_edit_message(
                             child.incoming.chat_id,
                             child.status_message_id,
-                            f"❌ **Cancelled:** Parent task failed",
+                            "❌ **Cancelled:** Parent task failed",
                             parse_mode="markdown",
                         )
                     )
diff --git a/messaging/telegram.py b/messaging/telegram.py
index 5ecfd80d..e987a51d 100644
--- a/messaging/telegram.py
+++ b/messaging/telegram.py
@@ -12,7 +12,7 @@ import os
 # This must be set BEFORE importing telegram.error
 os.environ["PTB_TIMEDELTA"] = "1"
 
-from typing import Callable, Awaitable, Optional, Any, Dict
+from typing import Callable, Awaitable, Optional, Any
 
 from .base import MessagingPlatform
 from .models import IncomingMessage
diff --git a/providers/exceptions.py b/providers/exceptions.py
index 9a694a35..d0099864 100644
--- a/providers/exceptions.py
+++ b/providers/exceptions.py
@@ -1,6 +1,6 @@
 """Unified exception hierarchy for providers."""
 
-from typing import Optional, Any
+from typing import Any
 
 
 class ProviderError(Exception):
diff --git a/providers/logging_utils.py b/providers/logging_utils.py
index 3d50170d..906aba3e 100644
--- a/providers/logging_utils.py
+++ b/providers/logging_utils.py
@@ -9,7 +9,7 @@ import json
 import logging
 import os
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, List, Optional
 
 logger = logging.getLogger(__name__)
 
diff --git a/providers/nvidia_mixins.py b/providers/nvidia_mixins.py
index ee86fb13..6e3610be 100644
--- a/providers/nvidia_mixins.py
+++ b/providers/nvidia_mixins.py
@@ -10,7 +10,7 @@ NVIDIA NIM provider functionality:
 
 import json
 import logging
-from typing import Any, Dict, AsyncIterator
+from typing import Any, Dict
 
 from .utils import AnthropicToOpenAIConverter, map_stop_reason, extract_think_content
 from .exceptions import (
diff --git a/providers/nvidia_nim.py b/providers/nvidia_nim.py
index 67ca724b..05fccc92 100644
--- a/providers/nvidia_nim.py
+++ b/providers/nvidia_nim.py
@@ -4,7 +4,7 @@ import logging
 import os
 import json
 import uuid
-from typing import Dict, Any, AsyncIterator
+from typing import Any, AsyncIterator
 
 import httpx
 from httpx import TimeoutException, ConnectTimeout
@@ -16,15 +16,9 @@ from .utils import (
     ThinkTagParser,
     HeuristicToolParser,
     ContentType,
-    extract_think_content,
     extract_reasoning_from_delta,
-    AnthropicToOpenAIConverter,
 )
 from .exceptions import (
-    AuthenticationError,
-    InvalidRequestError,
-    RateLimitError,
-    OverloadedError,
     APIError,
 )
 from .nvidia_mixins import (
@@ -73,7 +67,7 @@ class NvidiaNimProvider(
             message_id = f"msg_{uuid.uuid4()}"
             sse = SSEBuilder(message_id, request.model, input_tokens)
             error_msg = "⏱️ Global rate limit active. Resuming now..."
-            logger.info(f"NIM_STREAM: Reactive block detected, notified user")
+            logger.info("NIM_STREAM: Reactive block detected, notified user")
             yield sse.message_start()
             for event in sse.emit_error(error_msg):
                 yield event
@@ -179,7 +173,7 @@ class NvidiaNimProvider(
             error_message = (
                 f"⏱️ API Timeout ({timeout_type}): Request exceeded time limit"
             )
-            logger.info(f"NIM_STREAM: Emitting SSE error event for timeout")
+            logger.info("NIM_STREAM: Emitting SSE error event for timeout")
         except Exception as e:
             logger.error(f"NIM_ERROR: {type(e).__name__}: {e}")
             error_occurred = True
diff --git a/providers/utils/sse_builder.py b/providers/utils/sse_builder.py
index a1411135..44177fff 100644
--- a/providers/utils/sse_builder.py
+++ b/providers/utils/sse_builder.py
@@ -2,7 +2,7 @@
 
 import json
 from dataclasses import dataclass, field
-from typing import Optional, Dict, Any, Iterator, List
+from typing import Optional, Dict, Any, Iterator
 
 try:
     import tiktoken
diff --git a/tests/test_api.py b/tests/test_api.py
index 0e6c16b6..be8ce4e7 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1,4 +1,3 @@
-import pytest
 from fastapi.testclient import TestClient
 from api.app import app
 from api.dependencies import get_provider
diff --git a/tests/test_cli.py b/tests/test_cli.py
index 4b775a80..bf1749df 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -2,7 +2,6 @@
 
 import pytest
 import asyncio
-import json
 import os
 from unittest.mock import AsyncMock, MagicMock, patch
 
diff --git a/tests/test_config.py b/tests/test_config.py
index 7811ff7e..70669b73 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -1,7 +1,5 @@
 """Tests for config/settings.py"""
 
-import pytest
-import os
 
 
 class TestSettings:
diff --git a/tests/test_converter.py b/tests/test_converter.py
index 315e7301..ee128b96 100644
--- a/tests/test_converter.py
+++ b/tests/test_converter.py
@@ -1,5 +1,4 @@
 import json
-import pytest
 from providers.utils.message_converter import AnthropicToOpenAIConverter
 
 # --- Mock Classes ---
diff --git a/tests/test_dependencies.py b/tests/test_dependencies.py
index 983933ea..ecb8af8a 100644
--- a/tests/test_dependencies.py
+++ b/tests/test_dependencies.py
@@ -1,5 +1,4 @@
 import pytest
-import asyncio
 from unittest.mock import AsyncMock, MagicMock, patch
 from api.dependencies import get_provider, get_settings, cleanup_provider
 from providers.nvidia_nim import NvidiaNimProvider
diff --git a/tests/test_event_parser.py b/tests/test_event_parser.py
index b26a04eb..0ebae82b 100644
--- a/tests/test_event_parser.py
+++ b/tests/test_event_parser.py
@@ -1,4 +1,3 @@
-import pytest
 from messaging.event_parser import parse_cli_event
 
 
diff --git a/tests/test_handler.py b/tests/test_handler.py
index 100cea95..adb63d77 100644
--- a/tests/test_handler.py
+++ b/tests/test_handler.py
@@ -1,8 +1,6 @@
 import pytest
-import asyncio
 from unittest.mock import AsyncMock, MagicMock, patch
 from messaging.handler import ClaudeMessageHandler
-from messaging.models import IncomingMessage
 from messaging.tree_queue import MessageState
 
 
diff --git a/tests/test_limiter.py b/tests/test_limiter.py
index c2dd6fd8..71679a1b 100644
--- a/tests/test_limiter.py
+++ b/tests/test_limiter.py
@@ -4,7 +4,6 @@ import asyncio
 import time
 import os
 import logging
-from unittest.mock import MagicMock
 
 # Set environment variables relative to test execution
 os.environ["MESSAGING_RATE_LIMIT"] = "1"
diff --git a/tests/test_messaging.py b/tests/test_messaging.py
index 970098bb..5f10bd6e 100644
--- a/tests/test_messaging.py
+++ b/tests/test_messaging.py
@@ -4,7 +4,7 @@ import pytest
 import json
 import os
 from datetime import datetime, timedelta
-from unittest.mock import AsyncMock, MagicMock, patch, mock_open
+from unittest.mock import patch
 
 # --- Existing Tests ---
 
diff --git a/tests/test_model_utils.py b/tests/test_model_utils.py
index d0f6c28a..ba20ee48 100644
--- a/tests/test_model_utils.py
+++ b/tests/test_model_utils.py
@@ -1,4 +1,3 @@
-import pytest
 from providers.model_utils import (
     strip_provider_prefixes,
     is_claude_model,
diff --git a/tests/test_nvidia_nim.py b/tests/test_nvidia_nim.py
index 2f5f6a98..c061e036 100644
--- a/tests/test_nvidia_nim.py
+++ b/tests/test_nvidia_nim.py
@@ -4,12 +4,8 @@ import httpx
 from unittest.mock import MagicMock, AsyncMock, patch
 from providers.nvidia_nim import (
     NvidiaNimProvider,
-    RateLimitError,
     APIError,
-    OverloadedError,
 )
-from providers.base import ProviderConfig
-from providers.utils import ContentType
 
 
 # Mock data classes
diff --git a/tests/test_parsers.py b/tests/test_parsers.py
index c8bdb230..6aa30c82 100644
--- a/tests/test_parsers.py
+++ b/tests/test_parsers.py
@@ -1,4 +1,3 @@
-import pytest
 from providers.utils.think_parser import ThinkTagParser, ContentType
 from providers.utils.heuristic_tool_parser import HeuristicToolParser
 
diff --git a/tests/test_provider_rate_limit.py b/tests/test_provider_rate_limit.py
index d907a9bc..f5a32795 100644
--- a/tests/test_provider_rate_limit.py
+++ b/tests/test_provider_rate_limit.py
@@ -4,7 +4,6 @@ import asyncio
 import time
 import os
 import logging
-from unittest.mock import MagicMock
 
 from providers.rate_limit import GlobalRateLimiter
 
diff --git a/tests/test_reliability.py b/tests/test_reliability.py
index e1d7d4b2..d4b8d810 100644
--- a/tests/test_reliability.py
+++ b/tests/test_reliability.py
@@ -1,5 +1,4 @@
 import pytest
-import asyncio
 from unittest.mock import AsyncMock, MagicMock, patch
 from messaging.telegram import TelegramPlatform
 from telegram.error import NetworkError, RetryAfter, TelegramError
diff --git a/tests/test_request_utils.py b/tests/test_request_utils.py
index 99155257..cc66d2c1 100644
--- a/tests/test_request_utils.py
+++ b/tests/test_request_utils.py
@@ -1,6 +1,5 @@
 """Tests for api/request_utils.py module."""
 
-import pytest
 from unittest.mock import MagicMock
 
 from api.request_utils import (
diff --git a/tests/test_telegram.py b/tests/test_telegram.py
index a7ef59f4..c565fa0c 100644
--- a/tests/test_telegram.py
+++ b/tests/test_telegram.py
@@ -1,8 +1,6 @@
 import pytest
-import asyncio
 from unittest.mock import AsyncMock, MagicMock, patch
-from messaging.telegram import TelegramPlatform, TELEGRAM_AVAILABLE
-from messaging.models import IncomingMessage
+from messaging.telegram import TelegramPlatform
 
 
 @pytest.fixture
diff --git a/tests/test_tree_queue.py b/tests/test_tree_queue.py
index bdbcf3e6..7556ce55 100644
--- a/tests/test_tree_queue.py
+++ b/tests/test_tree_queue.py
@@ -2,7 +2,6 @@
 
 import pytest
 import asyncio
-from datetime import datetime
 
 from messaging.tree_queue import (
     MessageState,