diff --git a/gns3server/agent/__init__.py b/gns3server/agent/__init__.py
index dee2aaed1..082c6dd4a 100644
--- a/gns3server/agent/__init__.py
+++ b/gns3server/agent/__init__.py
@@ -57,7 +57,7 @@ except ImportError as e:
     AI_COPILOT_AVAILABLE = False
 
     # Provide stub functions that raise helpful errors
-    async def get_project_agent_manager():
+    async def get_project_agent_manager() -> "ProjectAgentManager":
         """
         Get the global ProjectAgentManager singleton instance.
 
@@ -68,7 +68,7 @@ except ImportError as e:
             "AI Copilot is not available. Install AI dependencies with: pip install gns3-server[ai-features]"
         )
 
-    class ProjectAgentManager:
+    class ProjectAgentManager:  # type: ignore[no-redef]
         """
         Stub class for ProjectAgentManager when AI dependencies are not installed.
         """
diff --git a/gns3server/agent/gns3_copilot/agent/context_manager.py b/gns3server/agent/gns3_copilot/agent/context_manager.py
index 79c526dbf..5337c3d95 100644
--- a/gns3server/agent/gns3_copilot/agent/context_manager.py
+++ b/gns3server/agent/gns3_copilot/agent/context_manager.py
@@ -140,7 +140,7 @@ def estimate_tool_tokens(tools: list[Any]) -> int:
     for tool in tools:
         try:
             # Build tool schema in OpenAI format
-            tool_schema = {
+            tool_schema: dict[str, Any] = {
                 "type": "function",
                 "function": {
                     "name": tool.name,
diff --git a/gns3server/agent/gns3_copilot/agent/model_factory.py b/gns3server/agent/gns3_copilot/agent/model_factory.py
index cfdc26854..f790646bd 100644
--- a/gns3server/agent/gns3_copilot/agent/model_factory.py
+++ b/gns3server/agent/gns3_copilot/agent/model_factory.py
@@ -110,7 +110,7 @@ def create_base_model(
 
     try:
         # Prepare parameters for init_chat_model
-        init_params = {
+        init_params: dict[str, Any] = {
             "model": config_vars["model_name"],
             "model_provider": config_vars["model_provider"],
             "api_key": config_vars["api_key"],
@@ -177,7 +177,7 @@ def create_title_model(
 
     try:
         # Prepare parameters for init_chat_model
-        init_params = {
+        init_params: dict[str, Any] = {
             "model": config_vars["model_name"],
             "model_provider": config_vars["model_provider"],
             "api_key": config_vars["api_key"],
diff --git a/gns3server/agent/gns3_copilot/chat_sessions_repository.py b/gns3server/agent/gns3_copilot/chat_sessions_repository.py
index 4d18d8852..41006f299 100644
--- a/gns3server/agent/gns3_copilot/chat_sessions_repository.py
+++ b/gns3server/agent/gns3_copilot/chat_sessions_repository.py
@@ -125,7 +125,7 @@ class ChatSessionsRepository:
         project_id: str,
         title: str = "New Conversation",
         copilot_mode: Optional[str] = None,
-    ) -> ChatSession:
+    ) -> Optional[ChatSession]:
         """
         Create a new chat session.
 
@@ -158,6 +158,8 @@ class ChatSessionsRepository:
         session_id = cursor.lastrowid
         log.info("Created chat session: id=%s, thread_id=%s, copilot_mode=%s", session_id, thread_id, copilot_mode)
 
+        if session_id is None:
+            return None
         return await self.get_session_by_id(session_id)
 
     async def get_session_by_id(self, session_id: int) -> Optional[ChatSession]:
@@ -214,7 +216,7 @@ class ChatSessionsRepository:
             List of ChatSession
         """
         query = "SELECT * FROM chat_sessions"
-        params = []
+        params: List[Any] = []
 
         conditions = []
         if user_id:
@@ -268,7 +270,7 @@ class ChatSessionsRepository:
             Updated ChatSession or None
         """
         updates = []
-        params = []
+        params: List[Any] = []
 
         now = datetime.utcnow().isoformat()
 
diff --git a/gns3server/agent/gns3_copilot/gns3_client/api_handlers.py b/gns3server/agent/gns3_copilot/gns3_client/api_handlers.py
index b0934c201..7f6ca8c95 100644
--- a/gns3server/agent/gns3_copilot/gns3_client/api_handlers.py
+++ b/gns3server/agent/gns3_copilot/gns3_client/api_handlers.py
@@ -162,14 +162,14 @@ def build_gns3_ctx(jwt_token: str | None = None, url: str | None = None) -> dict
     }
 
 
-def _filter_node_response(node: dict, fields: list[str] = None) -> dict:
+def _filter_node_response(node: dict, fields: list[str] | None = None) -> dict:
     """Filter node response to only include requested fields."""
     if not fields:
         fields = ["node_id", "name", "node_type", "status", "console"]
     return {k: node[k] for k in fields if k in node}
 
 
-def _filter_link_response(link: dict, fields: list[str] = None) -> dict:
+def _filter_link_response(link: dict, fields: list[str] | None = None) -> dict:
     """Filter link response to only include requested fields."""
     if not fields:
         fields = LINK_DEFAULT_FIELDS
@@ -278,7 +278,7 @@ def _batch_lifecycle(project_id, node_ids, action, conn, action_label):
         return list(pool.map(_act, node_ids))
 
 
-def start_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def start_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -296,7 +296,7 @@ def start_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict
     return {"message": f"Node {node_id} started", "node_id": node_id}
 
 
-def stop_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def stop_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -314,7 +314,7 @@ def stop_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[
     return {"message": f"Node {node_id} stopped", "node_id": node_id}
 
 
-def suspend_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def suspend_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -332,7 +332,7 @@ def suspend_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> di
     return {"message": f"Node {node_id} suspended", "node_id": node_id}
 
 
-def create_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def create_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
 
     project_id = params.get("project_id")
     if not project_id:
@@ -401,7 +401,7 @@ def create_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dic
     return _filter_node_response(resp, fields)
 
 
-def delete_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def delete_node_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -706,7 +706,7 @@ def available_filters_handler(params: dict[str, Any], gns3_ctx: dict[str, Any])
     return conn.http_call("get", url).json()
 
 
-def create_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def create_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -762,7 +762,7 @@ def create_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dic
     return _filter_link_response(resp, fields)
 
 
-def delete_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def delete_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
@@ -809,7 +809,7 @@ def update_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dic
 # ── Link capture / reset handlers ──────────────────────────────────────
 
 
-def reset_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any]:
+def reset_link_handler(params: dict[str, Any], gns3_ctx: dict[str, Any]) -> dict[str, Any] | list[dict[str, Any]]:
     project_id = params.get("project_id")
     if not project_id:
         return {"error": "project_id is required"}
diff --git a/gns3server/agent/gns3_copilot/gns3_client/connector_factory.py b/gns3server/agent/gns3_copilot/gns3_client/connector_factory.py
index c57dc8fee..32a4e2e45 100644
--- a/gns3server/agent/gns3_copilot/gns3_client/connector_factory.py
+++ b/gns3server/agent/gns3_copilot/gns3_client/connector_factory.py
@@ -347,7 +347,7 @@ def get_gns3_server_host() -> str:
         host = get_gns3_server_host()
         print(f"GNS3 server host: {host}")
     """
-    url = _detect_url_for_api()
+    url = _detect_url_for_api() or DEFAULT_GNS3_URL
 
     # Extract host from URL
     # URL format: protocol://host:port
diff --git a/gns3server/agent/gns3_copilot/gns3_client/project_inventory.py b/gns3server/agent/gns3_copilot/gns3_client/project_inventory.py
index b1f958767..aeefd304a 100644
--- a/gns3server/agent/gns3_copilot/gns3_client/project_inventory.py
+++ b/gns3server/agent/gns3_copilot/gns3_client/project_inventory.py
@@ -49,7 +49,7 @@ def build_nodes_inventory(nodes: list[dict[str, Any]], server_host: str | None)
     """
     inventory: dict[str, Any] = {}
     for n in nodes:
-        inventory[n.get("name")] = {
+        inventory[n.get("name") or ""] = {
             "server": server_host,
             "name": n.get("name"),
             "node_id": n.get("node_id"),
@@ -68,7 +68,7 @@ def build_nodes_inventory(nodes: list[dict[str, Any]], server_host: str | None)
     return inventory
 
 
-def build_links_summary(nodes: list[dict[str, Any]], links: list[dict[str, Any]]) -> list[dict[str, str]]:
+def build_links_summary(nodes: list[dict[str, Any]], links: list[dict[str, Any]]) -> list[dict[str, Any]]:
     """
     Build a human/LLM-friendly link list resolving node and port names.
 
@@ -76,7 +76,7 @@ def build_links_summary(nodes: list[dict[str, Any]], links: list[dict[str, Any]]
     Links whose endpoints cannot be resolved are skipped, mirroring the
     original Project.links_summary behavior.
     """
-    summary: list[dict[str, str]] = []
+    summary: list[dict[str, Any]] = []
     for link in links:
         if not link.get("nodes"):
             continue
diff --git a/gns3server/agent/gns3_copilot/skills/loader.py b/gns3server/agent/gns3_copilot/skills/loader.py
index 655d76263..0295e2520 100644
--- a/gns3server/agent/gns3_copilot/skills/loader.py
+++ b/gns3server/agent/gns3_copilot/skills/loader.py
@@ -248,7 +248,7 @@ class SkillsLoader:
                     continue
                 # Use device_type from YAML content as the key
                 # Fallback to filename stem if device_type not present
-                skill_key = skill_data.get("device_type") if isinstance(skill_data, dict) else None
+                skill_key = skill_data.get("device_type")
                 if not skill_key:
                     skill_key = yaml_file.stem
                     logger.warning(f"No device_type in {yaml_file}, using filename '{skill_key}' as key")
diff --git a/gns3server/agent/gns3_copilot/skills/manager.py b/gns3server/agent/gns3_copilot/skills/manager.py
index 473fb2b09..1a511ec29 100644
--- a/gns3server/agent/gns3_copilot/skills/manager.py
+++ b/gns3server/agent/gns3_copilot/skills/manager.py
@@ -37,8 +37,10 @@ from typing import Optional, Dict, Any
 
 try:
     import git
+
+    GIT_AVAILABLE = True
 except ImportError:
-    git = None
+    GIT_AVAILABLE = False
 
 from gns3server.config import Config
 from .loader import SkillsLoader
@@ -66,7 +68,7 @@ class SkillsManager:
     - Version tracking
     """
 
-    def __init__(self, repo_url: str = None, branch: str = "main", auto_update: bool = False):
+    def __init__(self, repo_url: Optional[str] = None, branch: str = "main", auto_update: bool = False):
         """
         Initialize the skills manager.
 
@@ -90,7 +92,7 @@ class SkillsManager:
         self._repo: Optional["git.Repo"] = None
         self._prompt_count = 0
 
-        if git is None:
+        if not GIT_AVAILABLE:
             logger.warning("GitPython is not installed. Skills management features will be limited.")
 
     def initialize(self) -> bool:
@@ -134,7 +136,7 @@ class SkillsManager:
         - Up to date → nothing
         - Network error → use existing files, log warning
         """
-        if git is None or self._repo is None:
+        if not GIT_AVAILABLE or self._repo is None:
             return
 
         # Check for uncommitted changes
@@ -173,7 +175,7 @@ class SkillsManager:
         Returns:
             True if successful, False otherwise
         """
-        if git is None:
+        if not GIT_AVAILABLE:
             logger.error("GitPython is not installed. Cannot clone repository.")
             return False
 
@@ -347,7 +349,7 @@ class SkillsManager:
         Returns:
             Commit hash as string, or empty string if not available
         """
-        if git is None or self._repo is None:
+        if not GIT_AVAILABLE or self._repo is None:
             try:
                 self._repo = git.Repo(self.local_path)
             except Exception:
@@ -409,7 +411,7 @@ class SkillsManager:
         Returns:
             True if successful, False otherwise
         """
-        if git is None:
+        if not GIT_AVAILABLE:
             logger.error("GitPython is not installed. Cannot rollback.")
             return False
 
@@ -436,7 +438,7 @@ class SkillsManager:
         Returns:
             List of commit information dictionaries
         """
-        if git is None:
+        if not GIT_AVAILABLE:
             return []
 
         try:
diff --git a/gns3server/agent/gns3_copilot/tools_v2/config_tools_nornir.py b/gns3server/agent/gns3_copilot/tools_v2/config_tools_nornir.py
index db215c6bf..ed15f0589 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/config_tools_nornir.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/config_tools_nornir.py
@@ -78,7 +78,7 @@ try:
     # so we use importlib to get the actual module
     import importlib
 
-    sd = importlib.import_module("netmiko.ssh_dispatcher")
+    sd: Any = importlib.import_module("netmiko.ssh_dispatcher")
 
     # Recalculate platforms lists to include custom device types
     sd.platforms = list(sd.CLASS_MAPPER.keys())
@@ -196,7 +196,7 @@ class ExecuteMultipleDeviceConfigCommands(BaseTool):
 
         # Validate input
         device_configs_list, project_id = self._validate_tool_input(tool_input)
-        if isinstance(device_configs_list, list) and len(device_configs_list) > 0 and "error" in device_configs_list[0]:
+        if len(device_configs_list) > 0 and "error" in device_configs_list[0]:
             return device_configs_list
 
         # Filter forbidden commands and store blocked commands info
diff --git a/gns3server/agent/gns3_copilot/tools_v2/display_tools_nornir.py b/gns3server/agent/gns3_copilot/tools_v2/display_tools_nornir.py
index 8c4a5281d..a8eb41bc4 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/display_tools_nornir.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/display_tools_nornir.py
@@ -78,7 +78,7 @@ try:
     # so we use importlib to get the actual module
     import importlib
 
-    sd = importlib.import_module("netmiko.ssh_dispatcher")
+    sd: Any = importlib.import_module("netmiko.ssh_dispatcher")
 
     # Recalculate platforms lists to include custom device types
     sd.platforms = list(sd.CLASS_MAPPER.keys())
@@ -199,7 +199,7 @@ class ExecuteMultipleDeviceCommands(BaseTool):
 
         # Validate input
         device_configs_list, project_id = self._validate_tool_input(tool_input)
-        if isinstance(device_configs_list, list) and len(device_configs_list) > 0 and "error" in device_configs_list[0]:
+        if len(device_configs_list) > 0 and "error" in device_configs_list[0]:
             return device_configs_list
 
         # Filter forbidden commands and store blocked commands info
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_create_link.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_create_link.py
index 8f926586b..ff11c6a44 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_create_link.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_create_link.py
@@ -222,6 +222,8 @@ class GNS3LinkTool(BaseTool):
                         },
                         gns3_ctx,
                     )
+                    if isinstance(link_resp, list):
+                        raise RuntimeError("Unexpected batch response when creating a single link")
                     if "error" in link_resp:
                         raise RuntimeError(link_resp["error"])
 
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_create_node.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_create_node.py
index a511de21f..bdbc0bf42 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_create_node.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_create_node.py
@@ -230,6 +230,8 @@ class GNS3CreateNodeTool(BaseTool):
                         },
                         gns3_ctx,
                     )
+                    if isinstance(created, list):
+                        raise RuntimeError("Unexpected batch response when creating a single node")
                     if "error" in created:
                         raise RuntimeError(created["error"])
                     node_info = {
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_packet_filter.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_packet_filter.py
index d94a0fc1d..be7af824f 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_packet_filter.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_packet_filter.py
@@ -286,7 +286,7 @@ class GNS3PacketFilterTool(BaseTool):
 
             # Check if output contains "Invalid" indicating syntax error
             if "Invalid" in result.stdout or "Invalid" in result.stderr:
-                error_lines = []
+                error_lines: list[str] = []
                 if "Invalid" in result.stderr:
                     error_lines.extend(line for line in result.stderr.split("\n") if "Invalid" in line)
                 if "Invalid" in result.stdout:
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_start_node.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_start_node.py
index 8e98c7480..4086cde1b 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_start_node.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_start_node.py
@@ -136,7 +136,11 @@ class GNS3StartNodeTool(BaseTool):
             results = []
             known_ids = [nid for nid in node_ids if nid in nodes_by_id]
             start_results = start_node_handler({"project_id": project_id, "node_ids": known_ids}, gns3_ctx)
-            start_errors = {r["node_id"]: r.get("error") for r in start_results if r.get("status") == "error"}
+            start_errors = (
+                {r["node_id"]: r.get("error") for r in start_results if r.get("status") == "error"}
+                if isinstance(start_results, list)
+                else {}
+            )
 
             # Get immediate status (likely 'starting' or 'stopped') — one call
             listing = get_nodes_handler({"project_id": project_id}, gns3_ctx)
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_stop_node.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_stop_node.py
index 3c0d8ef2c..d6965f19b 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_stop_node.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_stop_node.py
@@ -124,7 +124,11 @@ class GNS3StopNodeTool(BaseTool):
             results = []
             known_ids = [nid for nid in node_ids if nid in nodes_by_id]
             stop_results = stop_node_handler({"project_id": project_id, "node_ids": known_ids}, gns3_ctx)
-            stop_errors = {r["node_id"]: r.get("error") for r in stop_results if r.get("status") == "error"}
+            stop_errors = (
+                {r["node_id"]: r.get("error") for r in stop_results if r.get("status") == "error"}
+                if isinstance(stop_results, list)
+                else {}
+            )
 
             # Get updated status — one call
             listing = get_nodes_handler({"project_id": project_id}, gns3_ctx)
diff --git a/gns3server/agent/gns3_copilot/tools_v2/gns3_suspend_node.py b/gns3server/agent/gns3_copilot/tools_v2/gns3_suspend_node.py
index 74f9ba883..47a0cc4b1 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/gns3_suspend_node.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/gns3_suspend_node.py
@@ -130,7 +130,11 @@ class GNS3SuspendNodeTool(BaseTool):
             results = []
             known_ids = [nid for nid in node_ids if nid in nodes_by_id]
             suspend_results = suspend_node_handler({"project_id": project_id, "node_ids": known_ids}, gns3_ctx)
-            suspend_errors = {r["node_id"]: r.get("error") for r in suspend_results if r.get("status") == "error"}
+            suspend_errors = (
+                {r["node_id"]: r.get("error") for r in suspend_results if r.get("status") == "error"}
+                if isinstance(suspend_results, list)
+                else {}
+            )
 
             # Get updated status — one call
             listing = get_nodes_handler({"project_id": project_id}, gns3_ctx)
diff --git a/gns3server/agent/gns3_copilot/tools_v2/packet_analysis_tool.py b/gns3server/agent/gns3_copilot/tools_v2/packet_analysis_tool.py
index b9c35d141..c5f30bf79 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/packet_analysis_tool.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/packet_analysis_tool.py
@@ -143,7 +143,8 @@ class PacketAnalysisTool(BaseTool):
                 stderr=subprocess.DEVNULL,
                 text=True,
             )
-            tshark.stdout.close()
+            if tshark.stdout is not None:
+                tshark.stdout.close()
             stdout, _ = grep.communicate(timeout=30)
             tshark.wait(timeout=5)
         except Exception as e:
diff --git a/gns3server/agent/gns3_copilot/tools_v2/vpcs_tools_netmiko.py b/gns3server/agent/gns3_copilot/tools_v2/vpcs_tools_netmiko.py
index 3a8789cda..1315730c7 100644
--- a/gns3server/agent/gns3_copilot/tools_v2/vpcs_tools_netmiko.py
+++ b/gns3server/agent/gns3_copilot/tools_v2/vpcs_tools_netmiko.py
@@ -68,7 +68,7 @@ try:
     # CRITICAL: Update netmiko.ssh_dispatcher platforms lists
     import importlib
 
-    sd = importlib.import_module("netmiko.ssh_dispatcher")
+    sd: Any = importlib.import_module("netmiko.ssh_dispatcher")
 
     # Recalculate platforms lists to include custom device types
     sd.platforms = list(sd.CLASS_MAPPER.keys())
@@ -179,7 +179,7 @@ class VPCSCommands(BaseTool):
 
         # Validate input
         device_configs_list, project_id = self._validate_tool_input(tool_input)
-        if isinstance(device_configs_list, list) and len(device_configs_list) > 0 and "error" in device_configs_list[0]:
+        if len(device_configs_list) > 0 and "error" in device_configs_list[0]:
             return device_configs_list
 
         # Create a mapping of device names to their commands
@@ -386,7 +386,7 @@ class VPCSCommands(BaseTool):
     def _prepare_device_hosts_data(
         self,
         device_configs_list: list[dict[str, Any]],
-        project_id: str,
+        project_id: str | None,
         jwt_token: str | None = None,
         url: str | None = None,
     ) -> dict[str, dict[str, Any]]:
@@ -415,7 +415,7 @@ class VPCSCommands(BaseTool):
         device_ports = get_device_ports_from_topology(device_names, project_id=project_id, jwt_token=jwt_token, url=url)
 
         # Build Nornir inventory hosts data
-        hosts_data = {}
+        hosts_data: dict[str, Any] = {}
         for device_name in device_names:
             if device_name not in device_ports:
                 logger.error("Device '%s' not found in topology", device_name)
diff --git a/gns3server/agent/gns3_copilot/utils/custom_netmiko/scripts/list_netmiko_telnet_devices.py b/gns3server/agent/gns3_copilot/utils/custom_netmiko/scripts/list_netmiko_telnet_devices.py
index 3e951f10a..d4f7b1a38 100644
--- a/gns3server/agent/gns3_copilot/utils/custom_netmiko/scripts/list_netmiko_telnet_devices.py
+++ b/gns3server/agent/gns3_copilot/utils/custom_netmiko/scripts/list_netmiko_telnet_devices.py
@@ -169,7 +169,7 @@ def group_devices_by_brand(device_types: List[str]) -> Dict[str, List[str]]:
     Returns:
         Dictionary mapping brand names to device type lists
     """
-    brands = {}
+    brands: dict[str, list[str]] = {}
 
     for device_type in device_types:
         brand = extract_brand_name(device_type)
diff --git a/gns3server/agent/gns3_copilot/utils/message_converters.py b/gns3server/agent/gns3_copilot/utils/message_converters.py
index 8bf18f668..367b2d956 100644
--- a/gns3server/agent/gns3_copilot/utils/message_converters.py
+++ b/gns3server/agent/gns3_copilot/utils/message_converters.py
@@ -37,6 +37,7 @@ from typing import Dict
 from langchain_core.messages import AIMessage
 from langchain_core.messages import HumanMessage
 from langchain_core.messages import SystemMessage
+from langchain_core.messages import ToolCall
 from langchain_core.messages import ToolMessage
 
 
@@ -86,7 +87,7 @@ def convert_langchain_to_openai(lc_message) -> Dict[str, Any]:
             tool_calls = []
             for tc in lc_message.tool_calls:
                 # Convert to dict if it's an object
-                tc_dict = tc if isinstance(tc, dict) else tc.model_dump()
+                tc_dict = tc
                 tool_calls.append(
                     {
                         "id": tc_dict.get("id", str(uuid.uuid4())),
@@ -139,7 +140,7 @@ def convert_openai_to_langchain(msg: Dict[str, Any]):
 
         # Restore tool calls if present
         if "tool_calls" in msg and msg["tool_calls"]:
-            tool_calls = []
+            tool_calls: list[ToolCall] = []
             for tc in msg["tool_calls"]:
                 tool_calls.append(
                     {
diff --git a/gns3server/agent/gns3_copilot/utils/parse_tool_content.py b/gns3server/agent/gns3_copilot/utils/parse_tool_content.py
index 4ea17912d..350a6bf50 100644
--- a/gns3server/agent/gns3_copilot/utils/parse_tool_content.py
+++ b/gns3server/agent/gns3_copilot/utils/parse_tool_content.py
@@ -214,9 +214,7 @@ def parse_tool_content(
         return content
 
     # Handle unsupported types
-    error_msg = (  # type: ignore[unreachable]
-        f"Content must be str, dict, list, int, float, bool, or None, got {type(content).__name__}"
-    )
+    error_msg = f"Content must be str, dict, list, int, float, bool, or None, got {type(content).__name__}"
     logger.error(error_msg)
 
     if strict_mode:
diff --git a/gns3server/agent/mcp/appliances.py b/gns3server/agent/mcp/appliances.py
index 45a9b472a..6e3a3ecf5 100644
--- a/gns3server/agent/mcp/appliances.py
+++ b/gns3server/agent/mcp/appliances.py
@@ -108,7 +108,7 @@ def install_appliance_handler(params: dict[str, Any], gns3_ctx: dict[str, Any])
     if version:
         request_params["version"] = version
     response = conn.http_call("post", url, params=request_params)
-    result = {"message": f"Appliance {appliance_id} installed"}
+    result: dict[str, Any] = {"message": f"Appliance {appliance_id} installed"}
     if response.content:
         # the install endpoint returns the created template (201); tolerate an
         # empty body in case an older server still replies with 204
diff --git a/gns3server/agent/web_wireshark/docker_client.py b/gns3server/agent/web_wireshark/docker_client.py
index d27873fa5..00f62edd2 100644
--- a/gns3server/agent/web_wireshark/docker_client.py
+++ b/gns3server/agent/web_wireshark/docker_client.py
@@ -23,9 +23,16 @@ This module handles Docker API operations via aiohttp Unix socket.
 
 import asyncio
 import logging
+import sys
+from typing import Any
 
 import aiohttp
 
+if sys.version_info >= (3, 11):
+    from asyncio import timeout as async_timeout
+else:
+    from async_timeout import timeout as async_timeout
+
 from gns3server.utils import parse_version
 
 logger = logging.getLogger(__name__)
@@ -132,7 +139,7 @@ class DockerHTTPClient:
         url = f"http://docker/v{self._api_version}/{endpoint}"
 
         try:
-            async with asyncio.timeout(self.REQUEST_TIMEOUT):
+            async with async_timeout(self.REQUEST_TIMEOUT):
                 async with session.request(method, url, **kwargs) as response:
                     if response.status >= 300:
                         error_text = await response.text()
@@ -157,9 +164,9 @@ class DockerHTTPClient:
                 return await self._request(method, endpoint, check_connection=False, **kwargs)
             raise
 
-    async def create_network(self, name: str, driver: str = "bridge", subnet: str = None):
+    async def create_network(self, name: str, driver: str = "bridge", subnet: str | None = None):
         """Create Docker network."""
-        data = {"Name": name, "Driver": driver}
+        data: dict[str, Any] = {"Name": name, "Driver": driver}
         if subnet:
             data["IPAM"] = {"Config": [{"Subnet": subnet}]}
         await self._request("POST", "networks/create", json=data)
@@ -175,7 +182,7 @@ class DockerHTTPClient:
 
     async def create_container(self, name: str, image: str, **kwargs):
         """Create container."""
-        data = {"Image": image, "name": name, "HostConfig": {}, "NetworkingConfig": {}}
+        data: dict[str, Any] = {"Image": image, "name": name, "HostConfig": {}, "NetworkingConfig": {}}
 
         # Handle network config
         if "network" in kwargs:
@@ -248,7 +255,7 @@ class DockerHTTPClient:
         url = f"http://docker/v{self._api_version}/containers/{container_name}/top?ps_args=aux"
 
         try:
-            async with asyncio.timeout(self.REQUEST_TIMEOUT):
+            async with async_timeout(self.REQUEST_TIMEOUT):
                 async with session.get(url) as response:
                     if response.status >= 300:
                         error_text = await response.text()
diff --git a/gns3server/agent/web_wireshark/manage_wireshark.py b/gns3server/agent/web_wireshark/manage_wireshark.py
index 559eaadd9..5203a98d9 100755
--- a/gns3server/agent/web_wireshark/manage_wireshark.py
+++ b/gns3server/agent/web_wireshark/manage_wireshark.py
@@ -81,10 +81,7 @@ from gns3server.utils.uuid_validator import validate_uuid
 if __name__ == "__main__":
     sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))))
 
-try:
-    from gns3server.agent.web_wireshark.manager import WebWiresharkManager
-except ImportError:
-    from manager import WebWiresharkManager
+from gns3server.agent.web_wireshark.manager import WebWiresharkManager
 
 logger = logging.getLogger(__name__)
 
diff --git a/gns3server/agent/web_wireshark/manager.py b/gns3server/agent/web_wireshark/manager.py
index e17cf65c0..16f057d75 100644
--- a/gns3server/agent/web_wireshark/manager.py
+++ b/gns3server/agent/web_wireshark/manager.py
@@ -84,7 +84,7 @@ class WebWiresharkManager:
             logger.warning(f"Container {container_id[:12]} health check failed: {e}")
             return False
 
-    async def _exec_in_container(self, container_id: str, command: str, timeout: int = None) -> tuple:
+    async def _exec_in_container(self, container_id: str, command: str, timeout: Optional[int] = None) -> tuple:
         """Execute command in container with timeout.
 
         Args:
@@ -197,7 +197,7 @@ class WebWiresharkManager:
             stdout, _ = await proc.communicate()
 
             # Build parent->children mapping
-            children_map = {}
+            children_map: dict[int, list[int]] = {}
             for line in stdout.decode().strip().split("\n"):
                 parts = line.split(None, 2)
                 if len(parts) < 3:
@@ -326,7 +326,7 @@ class WebWiresharkManager:
                 return
 
             # Build parent->children mapping and collect process info
-            children_map = {}  # ppid -> [pid]
+            children_map: dict[int, list[int]] = {}  # ppid -> [pid]
             process_info = {}  # pid -> (ppid, command)
 
             for line in stdout.decode().strip().split("\n"):
@@ -480,7 +480,7 @@ class WebWiresharkManager:
             logger.debug(f"Cannot get URL from Config: {e}")
         return None
 
-    async def _get_container_gateway_ip(self, container_id: str = None) -> Optional[str]:
+    async def _get_container_gateway_ip(self, container_id: Optional[str] = None) -> Optional[str]:
         """Get the Docker bridge gateway IP for container to access host.
 
         Args:
@@ -519,7 +519,7 @@ class WebWiresharkManager:
 
         return None
 
-    async def get_container_ip(self, container_name: str, container_id: str = None) -> Optional[str]:
+    async def get_container_ip(self, container_name: str, container_id: Optional[str] = None) -> Optional[str]:
         """Get the container IP address in the wireshark network.
 
         Args:
@@ -626,7 +626,7 @@ class WebWiresharkManager:
         project_id: str,
         image: str = "gns3/web-wireshark:latest",
         memory: str = "2g",
-        memory_swap: str = None,
+        memory_swap: Optional[str] = None,
         cpus: float = 1.0,
         pids_limit: int = 1000,
     ) -> str:
@@ -935,10 +935,10 @@ class WebWiresharkManager:
         project_id: str,
         link_id: str,
         jwt_token: str,
-        capture_stream_url: str = None,
+        capture_stream_url: Optional[str] = None,
         image: str = "gns3/web-wireshark:latest",
         memory: str = "2g",
-        memory_swap: str = None,
+        memory_swap: Optional[str] = None,
         cpus: float = 1.0,
         pids_limit: int = 1000,
     ):
diff --git a/gns3server/agent/web_wireshark/stats.py b/gns3server/agent/web_wireshark/stats.py
index 78dc7b0c0..de9b66091 100644
--- a/gns3server/agent/web_wireshark/stats.py
+++ b/gns3server/agent/web_wireshark/stats.py
@@ -7,7 +7,7 @@ about Web Wireshark containers and sessions.
 
 import logging
 import subprocess
-from typing import Dict, List, Optional
+from typing import Any, Dict, List, Optional
 
 logger = logging.getLogger(__name__)
 
@@ -30,7 +30,7 @@ async def collect_webwireshark_stats(projects: List) -> Dict:
     """
     from .manager import WebWiresharkManager
 
-    stats = {"total_containers": 0, "running_containers": 0, "active_sessions": 0, "containers": []}
+    stats: Dict[str, Any] = {"total_containers": 0, "running_containers": 0, "active_sessions": 0, "containers": []}
 
     # Create a single manager instance and reuse it
     manager = WebWiresharkManager()
diff --git a/gns3server/api/routes/compute/atm_switch_nodes.py b/gns3server/api/routes/compute/atm_switch_nodes.py
index 65bc1157d..1282a162d 100644
--- a/gns3server/api/routes/compute/atm_switch_nodes.py
+++ b/gns3server/api/routes/compute/atm_switch_nodes.py
@@ -18,6 +18,7 @@
 API routes for ATM switch nodes.
 """
 
+from typing import Any
 import os
 
 from fastapi import APIRouter, Depends, Body, Path, status, HTTPException
@@ -29,7 +30,9 @@ from gns3server import schemas
 from gns3server.compute.dynamips import Dynamips
 from gns3server.compute.dynamips.nodes.atm_switch import ATMSwitch
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or ATM switch node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or ATM switch node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -57,13 +60,13 @@ async def create_atm_switch(project_id: UUID, node_data: schemas.ATMSwitchCreate
 
     # Use the Dynamips ATM switch to simulate this node
     dynamips_manager = Dynamips.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await dynamips_manager.create_node(
-        node_data.get("name"),
+        data.get("name"),
         str(project_id),
-        node_data.get("node_id"),
+        data.get("node_id"),
         node_type="atm_switch",
-        mappings=node_data.get("mappings"),
+        mappings=data.get("mappings"),
     )
     return node.asdict()
 
@@ -97,11 +100,11 @@ async def update_atm_switch(
     Update an ATM switch node.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    if "name" in node_data and node.name != node_data["name"]:
-        await node.set_name(node_data["name"])
-    if "mappings" in node_data:
-        node.mappings = node_data["mappings"]
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    if "name" in data and node.name != data["name"]:
+        await node.set_name(data["name"])
+    if "mappings" in data:
+        node.mappings = data["mappings"]
     node.updated()
     return node.asdict()
 
diff --git a/gns3server/api/routes/compute/capabilities.py b/gns3server/api/routes/compute/capabilities.py
index f472f6231..42154d4e1 100644
--- a/gns3server/api/routes/compute/capabilities.py
+++ b/gns3server/api/routes/compute/capabilities.py
@@ -39,7 +39,8 @@ def get_capabilities(request: Request) -> dict:
         node_types.extend(module.node_types())
 
     # record the controller hostname or IP address
-    request.app.state.controller_host = request.client.host
+    if request.client:
+        request.app.state.controller_host = request.client.host
 
     return {
         "version": __version__,
diff --git a/gns3server/api/routes/compute/cloud_nodes.py b/gns3server/api/routes/compute/cloud_nodes.py
index 7baf8ca17..d0a4ead9e 100644
--- a/gns3server/api/routes/compute/cloud_nodes.py
+++ b/gns3server/api/routes/compute/cloud_nodes.py
@@ -23,14 +23,16 @@ import os
 from fastapi import APIRouter, Depends, Path, status, HTTPException
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
-from typing import Union
+from typing import Any, Union
 from uuid import UUID
 
 from gns3server import schemas
 from gns3server.compute.builtin import Builtin
 from gns3server.compute.builtin.nodes.cloud import Cloud
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or cloud node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or cloud node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -57,21 +59,21 @@ async def create_cloud(project_id: UUID, node_data: schemas.CloudCreate) -> sche
     """
 
     builtin_manager = Builtin.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await builtin_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
+        data.get("node_id"),
         node_type="cloud",
-        ports=node_data.get("ports_mapping"),
+        ports=data.get("ports_mapping"),
     )
 
     # add the remote console settings
-    node.remote_console_host = node_data.get("remote_console_host", node.remote_console_host)
-    node.remote_console_port = node_data.get("remote_console_port", node.remote_console_port)
-    node.remote_console_type = node_data.get("remote_console_type", node.remote_console_type)
-    node.remote_console_http_path = node_data.get("remote_console_http_path", node.remote_console_http_path)
-    node.usage = node_data.get("usage", "")
+    node.remote_console_host = data.get("remote_console_host", node.remote_console_host)
+    node.remote_console_port = data.get("remote_console_port", node.remote_console_port)
+    node.remote_console_type = data.get("remote_console_type", node.remote_console_type)
+    node.remote_console_http_path = data.get("remote_console_http_path", node.remote_console_http_path)
+    node.usage = data.get("usage", "")
     return node.asdict()
 
 
@@ -90,8 +92,8 @@ async def update_cloud(node_data: schemas.CloudUpdate, node: Cloud = Depends(dep
     Update a cloud node.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    for name, value in node_data.items():
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    for name, value in data.items():
         if hasattr(node, name) and getattr(node, name) != value:
             setattr(node, name, value)
     node.updated()
@@ -178,7 +180,7 @@ async def update_cloud_nio(
 
     nio = node.get_nio(port_number)
     nio.filters.clear()
-    if nio_data.filters:
+    if isinstance(nio_data, schemas.UDPNIO) and nio_data.filters:
         nio.filters = nio_data.filters
     # NIO type is a Union (Ethernet/TAP/UDP); only UDPNIO carries markers.
     nio.markers = getattr(nio_data, "markers", None) or {}
diff --git a/gns3server/api/routes/compute/compute.py b/gns3server/api/routes/compute/compute.py
index 1a862787c..c98b1a256 100644
--- a/gns3server/api/routes/compute/compute.py
+++ b/gns3server/api/routes/compute/compute.py
@@ -163,7 +163,7 @@ def compute_statistics() -> dict:
 
 @router.get("/qemu/capabilities")
 async def get_qemu_capabilities() -> dict:
-    capabilities = {"kvm": []}
+    capabilities: dict[str, list] = {"kvm": []}
     kvms = await Qemu.get_kvm_archs()
     if kvms:
         capabilities["kvm"] = kvms
diff --git a/gns3server/api/routes/compute/dependencies/authentication.py b/gns3server/api/routes/compute/dependencies/authentication.py
index 14ba07f91..0412a4136 100644
--- a/gns3server/api/routes/compute/dependencies/authentication.py
+++ b/gns3server/api/routes/compute/dependencies/authentication.py
@@ -91,9 +91,9 @@ async def ws_compute_authentication(websocket: WebSocket) -> Union[None, WebSock
         if not separator:
             raise invalid_user_credentials_exc
 
-        username = secrets.compare_digest(username, server_settings.compute_username)
-        password = secrets.compare_digest(password, server_settings.compute_password.get_secret_value())
-        if not (username and password):
+        username_valid = secrets.compare_digest(username, server_settings.compute_username)
+        password_valid = secrets.compare_digest(password, server_settings.compute_password.get_secret_value())
+        if not (username_valid and password_valid):
             raise invalid_user_credentials_exc
 
     except HTTPException as e:
@@ -101,5 +101,6 @@ async def ws_compute_authentication(websocket: WebSocket) -> Union[None, WebSock
         websocket_error = {"action": "log.error", "event": {"message": err_msg}}
         await websocket.send_json(websocket_error)
         log.error(err_msg)
-        return await websocket.close(code=1008)
+        await websocket.close(code=1008)
+        return None
     return websocket
diff --git a/gns3server/api/routes/compute/docker_nodes.py b/gns3server/api/routes/compute/docker_nodes.py
index 6091cf37b..9dee90dda 100644
--- a/gns3server/api/routes/compute/docker_nodes.py
+++ b/gns3server/api/routes/compute/docker_nodes.py
@@ -24,14 +24,16 @@ from fastapi import APIRouter, WebSocket, Depends, Body, status, HTTPException
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
 from uuid import UUID
-from typing import Union
+from typing import Any, Union
 
 from gns3server import schemas
 from gns3server.compute.docker import Docker
 from gns3server.compute.docker.docker_vm import DockerVM
 from .dependencies.authentication import compute_authentication, ws_compute_authentication
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or Docker node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or Docker node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -53,13 +55,13 @@ def dep_node(project_id: UUID, node_id: UUID) -> DockerVM:
     responses={409: {"model": schemas.ErrorMessage, "description": "Could not create Docker node"}},
     dependencies=[Depends(compute_authentication)],
 )
-async def create_docker_node(project_id: UUID, node_data: schemas.DockerCreate) -> schemas.Docker:
+async def create_docker_node(project_id: UUID, node_create: schemas.DockerCreate) -> schemas.Docker:
     """
     Create a new Docker node.
     """
 
     docker_manager = Docker.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    node_data = jsonable_encoder(node_create, exclude_unset=True)
     container = await docker_manager.create_node(
         node_data.pop("name"),
         str(project_id),
@@ -124,7 +126,7 @@ def get_docker_node(node: DockerVM = Depends(dep_node)) -> schemas.Docker:
 
 
 @router.put("/{node_id}", response_model=schemas.Docker, dependencies=[Depends(compute_authentication)])
-async def update_docker_node(node_data: schemas.DockerUpdate, node: DockerVM = Depends(dep_node)) -> schemas.Docker:
+async def update_docker_node(node_update: schemas.DockerUpdate, node: DockerVM = Depends(dep_node)) -> schemas.Docker:
     """
     Update a Docker node.
     """
@@ -152,7 +154,7 @@ async def update_docker_node(node_data: schemas.DockerUpdate, node: DockerVM = D
     ]
 
     changed = False
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    node_data = jsonable_encoder(node_update, exclude_unset=True)
     for prop in props:
         # hasattr: startup_config_content only exists on IOLDockerVM
         if prop in node_data and hasattr(node, prop) and node_data[prop] != getattr(node, prop):
diff --git a/gns3server/api/routes/compute/dynamips_nodes.py b/gns3server/api/routes/compute/dynamips_nodes.py
index ce1c1b42b..ccfcd58fb 100644
--- a/gns3server/api/routes/compute/dynamips_nodes.py
+++ b/gns3server/api/routes/compute/dynamips_nodes.py
@@ -23,7 +23,7 @@ import os
 from fastapi import APIRouter, WebSocket, Body, Depends, status, HTTPException
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
-from typing import List, Union
+from typing import Any, List, Optional, Union
 from uuid import UUID
 
 from gns3server.compute.dynamips import Dynamips
@@ -32,7 +32,9 @@ from gns3server import schemas
 
 from .dependencies.authentication import compute_authentication, ws_compute_authentication
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or Dynamips node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or Dynamips node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -64,25 +66,26 @@ async def create_router(project_id: UUID, node_data: schemas.DynamipsCreate) ->
 
     dynamips_manager = Dynamips.instance()
     platform = node_data.platform
+    chassis: Optional[str]
     if not node_data.chassis and platform in DEFAULT_CHASSIS:
         chassis = DEFAULT_CHASSIS[platform]
     else:
         chassis = node_data.chassis
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     vm = await dynamips_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
-        dynamips_id=node_data.get("dynamips_id"),
+        data.get("node_id"),
+        dynamips_id=data.get("dynamips_id"),
         platform=platform,
-        console=node_data.get("console"),
-        console_type=node_data.get("console_type", "telnet"),
-        aux=node_data.get("aux"),
-        aux_type=node_data.pop("aux_type", "none"),
+        console=data.get("console"),
+        console_type=data.get("console_type", "telnet"),
+        aux=data.get("aux"),
+        aux_type=data.pop("aux_type", "none"),
         chassis=chassis,
         node_type="dynamips",
     )
-    await dynamips_manager.update_vm_settings(vm, node_data)
+    await dynamips_manager.update_vm_settings(vm, data)
     return vm.asdict()
 
 
diff --git a/gns3server/api/routes/compute/ethernet_hub_nodes.py b/gns3server/api/routes/compute/ethernet_hub_nodes.py
index 350105789..150d18e64 100644
--- a/gns3server/api/routes/compute/ethernet_hub_nodes.py
+++ b/gns3server/api/routes/compute/ethernet_hub_nodes.py
@@ -18,6 +18,7 @@
 API routes for Ethernet hub nodes.
 """
 
+from typing import Any
 import os
 
 from fastapi import APIRouter, Depends, Body, Path, status, HTTPException
@@ -29,7 +30,9 @@ from gns3server.compute.dynamips import Dynamips
 from gns3server.compute.dynamips.nodes.ethernet_hub import EthernetHub
 from gns3server import schemas
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or Ethernet hub node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or Ethernet hub node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -57,13 +60,13 @@ async def create_ethernet_hub(project_id: UUID, node_data: schemas.EthernetHubCr
 
     # Use the Dynamips Ethernet hub to simulate this node
     dynamips_manager = Dynamips.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await dynamips_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
+        data.get("node_id"),
         node_type="ethernet_hub",
-        ports=node_data.get("ports_mapping"),
+        ports=data.get("ports_mapping"),
     )
     return node.asdict()
 
@@ -97,11 +100,11 @@ async def update_ethernet_hub(
     Update an Ethernet hub.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    if "name" in node_data and node.name != node_data["name"]:
-        await node.set_name(node_data["name"])
-    if "ports_mapping" in node_data:
-        node.ports_mapping = node_data["ports_mapping"]
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    if "name" in data and node.name != data["name"]:
+        await node.set_name(data["name"])
+    if "ports_mapping" in data:
+        node.ports_mapping = data["ports_mapping"]
     node.updated()
     return node.asdict()
 
diff --git a/gns3server/api/routes/compute/ethernet_switch_nodes.py b/gns3server/api/routes/compute/ethernet_switch_nodes.py
index bedfac0b6..9c7736e9c 100644
--- a/gns3server/api/routes/compute/ethernet_switch_nodes.py
+++ b/gns3server/api/routes/compute/ethernet_switch_nodes.py
@@ -22,6 +22,7 @@ through uBridge's ``brctl`` module (see
 ``gns3server.compute.builtin.nodes.ethernet_switch``).
 """
 
+from typing import Any
 import os
 
 from fastapi import APIRouter, Depends, Body, Path, status, HTTPException
@@ -33,7 +34,9 @@ from gns3server.compute.builtin import Builtin
 from gns3server.compute.builtin.nodes.ethernet_switch import EthernetSwitch
 from gns3server import schemas
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or Ethernet switch node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or Ethernet switch node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -60,17 +63,17 @@ async def create_ethernet_switch(project_id: UUID, node_data: schemas.EthernetSw
     """
 
     builtin_manager = Builtin.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await builtin_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
-        console=node_data.get("console"),
-        console_type=node_data.get("console_type"),
+        data.get("node_id"),
+        console=data.get("console"),
+        console_type=data.get("console_type"),
         node_type="ethernet_switch",
-        ports=node_data.get("ports_mapping"),
+        ports=data.get("ports_mapping"),
     )
-    node.usage = node_data.get("usage", "")
+    node.usage = data.get("usage", "")
     return node.asdict()
 
 
@@ -100,16 +103,16 @@ async def update_ethernet_switch(
     Update an Ethernet switch.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    if "name" in node_data and node.name != node_data["name"]:
-        node.name = node_data["name"]
-    if "usage" in node_data:
-        node.usage = node_data["usage"]
-    if "ports_mapping" in node_data:
-        node.ports_mapping = node_data["ports_mapping"]
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    if "name" in data and node.name != data["name"]:
+        node.name = data["name"]
+    if "usage" in data:
+        node.usage = data["usage"]
+    if "ports_mapping" in data:
+        node.ports_mapping = data["ports_mapping"]
         await node.update_port_settings()
-    if "console_type" in node_data:
-        node.console_type = node_data["console_type"]
+    if "console_type" in data:
+        node.console_type = data["console_type"]
     node.updated()
     return node.asdict()
 
diff --git a/gns3server/api/routes/compute/frame_relay_switch_nodes.py b/gns3server/api/routes/compute/frame_relay_switch_nodes.py
index f425b3200..bd8bb1f18 100644
--- a/gns3server/api/routes/compute/frame_relay_switch_nodes.py
+++ b/gns3server/api/routes/compute/frame_relay_switch_nodes.py
@@ -18,6 +18,7 @@
 API routes for Frame Relay switch nodes.
 """
 
+from typing import Any
 import os
 
 from fastapi import APIRouter, Depends, Body, Path, status, HTTPException
@@ -29,7 +30,9 @@ from gns3server import schemas
 from gns3server.compute.dynamips import Dynamips
 from gns3server.compute.dynamips.nodes.frame_relay_switch import FrameRelaySwitch
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or Frame Relay switch node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or Frame Relay switch node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -59,13 +62,13 @@ async def create_frame_relay_switch(
 
     # Use the Dynamips Frame Relay switch to simulate this node
     dynamips_manager = Dynamips.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await dynamips_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
+        data.get("node_id"),
         node_type="frame_relay_switch",
-        mappings=node_data.get("mappings"),
+        mappings=data.get("mappings"),
     )
     return node.asdict()
 
@@ -99,11 +102,11 @@ async def update_frame_relay_switch(
     Update an Frame Relay switch node.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    if "name" in node_data and node.name != node_data["name"]:
-        await node.set_name(node_data["name"])
-    if "mappings" in node_data:
-        node.mappings = node_data["mappings"]
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    if "name" in data and node.name != data["name"]:
+        await node.set_name(data["name"])
+    if "mappings" in data:
+        node.mappings = data["mappings"]
     node.updated()
     return node.asdict()
 
diff --git a/gns3server/api/routes/compute/iou_nodes.py b/gns3server/api/routes/compute/iou_nodes.py
index 0282d0f0f..5285c07b5 100644
--- a/gns3server/api/routes/compute/iou_nodes.py
+++ b/gns3server/api/routes/compute/iou_nodes.py
@@ -23,7 +23,7 @@ import os
 from fastapi import APIRouter, WebSocket, Depends, Body, status, HTTPException
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
-from typing import Union
+from typing import Any, Union
 from uuid import UUID
 
 from gns3server import schemas
@@ -32,7 +32,9 @@ from gns3server.compute.iou.iou_vm import IOUVM
 
 from .dependencies.authentication import compute_authentication, ws_compute_authentication
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or IOU node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or IOU node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -60,18 +62,18 @@ async def create_iou_node(project_id: UUID, node_data: schemas.IOUCreate) -> sch
     """
 
     iou = IOU.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     vm = await iou.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
-        application_id=node_data.get("application_id"),
-        path=node_data.get("path"),
-        console=node_data.get("console"),
-        console_type=node_data.get("console_type", "telnet"),
+        data.get("node_id"),
+        application_id=data.get("application_id"),
+        path=data.get("path"),
+        console=data.get("console"),
+        console_type=data.get("console_type", "telnet"),
     )
 
-    for name, value in node_data.items():
+    for name, value in data.items():
         if hasattr(vm, name) and getattr(vm, name) != value:
             if name == "application_id":
                 continue  # we must ignore this to avoid overwriting the application_id allocated by the controller
@@ -79,7 +81,7 @@ async def create_iou_node(project_id: UUID, node_data: schemas.IOUCreate) -> sch
                 continue
             if name == "private_config_content" and (vm.private_config_content and len(vm.private_config_content) > 0):
                 continue
-            if node_data.get("use_default_iou_values") and (name == "ram" or name == "nvram"):
+            if data.get("use_default_iou_values") and (name == "ram" or name == "nvram"):
                 continue
             setattr(vm, name, value)
     return vm.asdict()
@@ -100,8 +102,8 @@ async def update_iou_node(node_data: schemas.IOUUpdate, node: IOUVM = Depends(de
     Update an IOU node.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    for name, value in node_data.items():
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    for name, value in data.items():
         if hasattr(node, name) and getattr(node, name) != value:
             if name == "application_id":
                 continue  # we must ignore this to avoid overwriting the application_id allocated by the IOU manager
@@ -147,8 +149,8 @@ async def start_iou_node(start_data: schemas.IOUStart, node: IOUVM = Depends(dep
     Start an IOU node.
     """
 
-    start_data = jsonable_encoder(start_data, exclude_unset=True)
-    for name, value in start_data.items():
+    start_values = jsonable_encoder(start_data, exclude_unset=True)
+    for name, value in start_values.items():
         if hasattr(node, name) and getattr(node, name) != value:
             setattr(node, name, value)
 
@@ -223,7 +225,7 @@ async def update_iou_node_nio(
 
     nio = node.get_nio(adapter_number, port_number)
     nio.filters.clear()
-    if nio_data.filters:
+    if isinstance(nio_data, schemas.UDPNIO) and nio_data.filters:
         nio.filters = nio_data.filters
     # NIO type is a Union (Ethernet/TAP/UDP); only UDPNIO carries markers.
     nio.markers = getattr(nio_data, "markers", None) or {}
diff --git a/gns3server/api/routes/compute/nat_nodes.py b/gns3server/api/routes/compute/nat_nodes.py
index 60654b603..37d8b4401 100644
--- a/gns3server/api/routes/compute/nat_nodes.py
+++ b/gns3server/api/routes/compute/nat_nodes.py
@@ -23,14 +23,16 @@ import os
 from fastapi import APIRouter, Depends, Path, status, HTTPException
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
-from typing import Union
+from typing import Any, Union
 from uuid import UUID
 
 from gns3server import schemas
 from gns3server.compute.builtin import Builtin
 from gns3server.compute.builtin.nodes.nat import Nat
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or NAT node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or NAT node"}
+}
 
 router = APIRouter(responses=responses)
 
@@ -57,16 +59,16 @@ async def create_nat_node(project_id: UUID, node_data: schemas.NATCreate) -> sch
     """
 
     builtin_manager = Builtin.instance()
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    data = jsonable_encoder(node_data, exclude_unset=True)
     node = await builtin_manager.create_node(
-        node_data.pop("name"),
+        data.pop("name"),
         str(project_id),
-        node_data.get("node_id"),
+        data.get("node_id"),
         node_type="nat",
-        ports=node_data.get("ports_mapping"),
+        ports=data.get("ports_mapping"),
     )
 
-    node.usage = node_data.get("usage", "")
+    node.usage = data.get("usage", "")
     return node.asdict()
 
 
@@ -85,8 +87,8 @@ async def update_nat_node(node_data: schemas.NATUpdate, node: Nat = Depends(dep_
     Update a NAT node.
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
-    for name, value in node_data.items():
+    data = jsonable_encoder(node_data, exclude_unset=True)
+    for name, value in data.items():
         if hasattr(node, name) and getattr(node, name) != value:
             setattr(node, name, value)
     node.updated()
@@ -170,7 +172,7 @@ async def update_nat_node_nio(
 
     nio = node.get_nio(port_number)
     nio.filters.clear()
-    if nio_data.filters:
+    if isinstance(nio_data, schemas.UDPNIO) and nio_data.filters:
         nio.filters = nio_data.filters
     await node.update_nio(port_number, nio)
     return nio.asdict()
diff --git a/gns3server/api/routes/compute/notifications.py b/gns3server/api/routes/compute/notifications.py
index 2c6ca4ad5..ee533037b 100644
--- a/gns3server/api/routes/compute/notifications.py
+++ b/gns3server/api/routes/compute/notifications.py
@@ -39,14 +39,15 @@ async def project_ws_notifications(websocket: Union[None, WebSocket] = Depends(w
     """
 
     if websocket:
-        log.info(f"New client {websocket.client.host}:{websocket.client.port} has connected to compute WebSocket")
+        client = f"{websocket.client.host}:{websocket.client.port}" if websocket.client else "unknown"
+        log.info(f"New client {client} has connected to compute WebSocket")
         try:
             with NotificationManager.instance().queue() as queue:
                 while True:
                     notification = await queue.get_json(5)
                     await websocket.send_text(notification)
         except (ConnectionClosed, WebSocketDisconnect):
-            log.info(f"Client {websocket.client.host}:{websocket.client.port} has disconnected from compute WebSocket")
+            log.info(f"Client {client} has disconnected from compute WebSocket")
         except WebSocketException as e:
             log.warning(f"Error while sending to controller event to WebSocket client: {e}")
 
diff --git a/gns3server/api/routes/controller/api_keys.py b/gns3server/api/routes/controller/api_keys.py
index 235cbe7de..a3bfa4b14 100644
--- a/gns3server/api/routes/controller/api_keys.py
+++ b/gns3server/api/routes/controller/api_keys.py
@@ -39,7 +39,7 @@ API_KEY_PREFIX = "gns3_"
 API_KEY_BYTES = 32
 
 
-def _generate_api_key(api_key_id: UUID = None) -> tuple[str, str, str, UUID]:
+def _generate_api_key(api_key_id: UUID | None = None) -> tuple[str, str, str, UUID]:
     if api_key_id is None:
         api_key_id = uuid4()
     random_bytes = secrets.token_hex(API_KEY_BYTES)
diff --git a/gns3server/api/routes/controller/chat.py b/gns3server/api/routes/controller/chat.py
index cc796fe26..e55e722f7 100644
--- a/gns3server/api/routes/controller/chat.py
+++ b/gns3server/api/routes/controller/chat.py
@@ -23,7 +23,7 @@ Nested under projects: /v3/projects/{project_id}/chat/...
 import json
 import logging
 import uuid
-from typing import List, Optional
+from typing import Any, List, Optional
 
 from fastapi import APIRouter, Depends, HTTPException, Request, status
 from fastapi.responses import StreamingResponse
@@ -40,7 +40,7 @@ from .dependencies.authentication import get_current_active_user
 
 log = logging.getLogger(__name__)
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Resource not found"}}
+responses: dict[int | str, dict[str, Any]] = {404: {"model": schemas.ErrorMessage, "description": "Resource not found"}}
 
 router = APIRouter(responses=responses)
 
diff --git a/gns3server/api/routes/controller/drawings.py b/gns3server/api/routes/controller/drawings.py
index 42e989f0f..6df9ddd91 100644
--- a/gns3server/api/routes/controller/drawings.py
+++ b/gns3server/api/routes/controller/drawings.py
@@ -20,7 +20,7 @@ API routes for drawings.
 
 from fastapi import APIRouter, Depends, status
 from fastapi.encoders import jsonable_encoder
-from typing import List
+from typing import Any, List
 from uuid import UUID
 
 from gns3server.controller import Controller
@@ -30,7 +30,9 @@ from gns3server import schemas
 from .dependencies.database import get_repository
 from .dependencies.rbac import has_privilege
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Project or drawing not found"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Project or drawing not found"}
+}
 
 router = APIRouter(responses=responses)
 
diff --git a/gns3server/api/routes/controller/nodes.py b/gns3server/api/routes/controller/nodes.py
index 0938ab087..8cd7c0ade 100644
--- a/gns3server/api/routes/controller/nodes.py
+++ b/gns3server/api/routes/controller/nodes.py
@@ -27,7 +27,7 @@ from fastapi import APIRouter, Depends, WebSocket, WebSocketDisconnect, Request,
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
 from fastapi.routing import APIRoute
-from typing import List, Callable, Optional
+from typing import Any, List, Callable, Optional
 from uuid import UUID
 
 from gns3server.controller import Controller
@@ -47,7 +47,7 @@ import logging
 
 log = logging.getLogger(__name__)
 
-node_locks = {}
+node_locks: dict[str, dict[str, Any]] = {}
 
 
 class NodeConcurrency(APIRoute):
@@ -84,7 +84,9 @@ class NodeConcurrency(APIRoute):
         return custom_route_handler
 
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or node"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or node"}
+}
 
 router = APIRouter(route_class=NodeConcurrency, responses=responses)
 
@@ -127,7 +129,7 @@ def _check_node_type(node: Node, *required_types: str) -> None:
     },
     dependencies=[Depends(has_privilege("Node.Allocate"))],
 )
-async def create_node(node_data: schemas.NodeCreate, project: Project = Depends(dep_project)) -> schemas.Node:
+async def create_node(node_create: schemas.NodeCreate, project: Project = Depends(dep_project)) -> schemas.Node:
     """
     Create a new node.
 
@@ -135,8 +137,8 @@ async def create_node(node_data: schemas.NodeCreate, project: Project = Depends(
     """
 
     controller = Controller.instance()
-    compute = controller.get_compute(str(node_data.compute_id))
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    compute = controller.get_compute(str(node_create.compute_id))
+    node_data = jsonable_encoder(node_create, exclude_unset=True)
     node = await project.add_node(compute, node_data.pop("name"), node_data.pop("node_id", None), **node_data)
     return node.asdict()
 
@@ -274,14 +276,14 @@ async def get_node(node: Node = Depends(dep_node)) -> schemas.Node:
     response_model_exclude_unset=True,
     dependencies=[Depends(has_privilege("Node.Modify"))],
 )
-async def update_node(node_data: schemas.NodeUpdate, node: Node = Depends(dep_node)) -> schemas.Node:
+async def update_node(node_update: schemas.NodeUpdate, node: Node = Depends(dep_node)) -> schemas.Node:
     """
     Update a node.
 
     Required privilege: Node.Modify
     """
 
-    node_data = jsonable_encoder(node_data, exclude_unset=True)
+    node_data = jsonable_encoder(node_update, exclude_unset=True)
 
     # Ignore these because we only use them when creating a node
     node_data.pop("node_id", None)
@@ -654,9 +656,8 @@ async def ws_console(
         return
 
     compute = node.compute
-    log.info(
-        f"New client {websocket.client.host}:{websocket.client.port} has connected to controller console WebSocket"
-    )
+    client = f"{websocket.client.host}:{websocket.client.port}" if websocket.client else "unknown"
+    log.info(f"New client {client} has connected to controller console WebSocket")
 
     compute_host = compute.host
     try:
@@ -690,9 +691,7 @@ async def ws_console(
                     await ws_console_compute.send_bytes(msg["bytes"])
         except WebSocketDisconnect:
             pass
-        log.info(
-            f"Client {websocket.client.host}:{websocket.client.port} has disconnected from controller console WebSocket"
-        )
+        log.info(f"Client {client} has disconnected from controller console WebSocket")
 
     async def ws_send(ws_console_compute):
         """
@@ -709,10 +708,7 @@ async def ws_console(
                     break
         except WebSocketDisconnect:
             # the client disconnected while the compute was still streaming console output
-            log.info(
-                f"Client {websocket.client.host}:{websocket.client.port} has disconnected from controller"
-                f" console WebSocket"
-            )
+            log.info(f"Client {client} has disconnected from controller console WebSocket")
 
     try:
         # forward WebSocket data in both directions between the client and the compute console WebSocket
@@ -763,9 +759,8 @@ async def vnc_console(
         return
 
     compute = node.compute
-    log.info(
-        f"New client {websocket.client.host}:{websocket.client.port} has connected to controller VNC console WebSocket"
-    )
+    client = f"{websocket.client.host}:{websocket.client.port}" if websocket.client else "unknown"
+    log.info(f"New client {client} has connected to controller VNC console WebSocket")
 
     compute_host = compute.host
     try:
@@ -796,10 +791,7 @@ async def vnc_console(
                     await vnc_console_compute.send_bytes(data)
         except WebSocketDisconnect:
             pass
-        log.info(
-            f"Client {websocket.client.host}:{websocket.client.port} has disconnected from controller"
-            f" VNC console WebSocket"
-        )
+        log.info(f"Client {client} has disconnected from controller VNC console WebSocket")
 
     async def vnc_send(vnc_console_compute):
         """
@@ -814,10 +806,7 @@ async def vnc_console(
                     break
         except WebSocketDisconnect:
             # the client disconnected while the compute was still streaming VNC console output
-            log.info(
-                f"Client {websocket.client.host}:{websocket.client.port} has disconnected from controller"
-                f" VNC console WebSocket"
-            )
+            log.info(f"Client {client} has disconnected from controller VNC console WebSocket")
 
     try:
         # forward WebSocket data in both directions between the client and the compute VNC console WebSocket
diff --git a/gns3server/api/routes/controller/privileges.py b/gns3server/api/routes/controller/privileges.py
index a070a6ee6..1f34ec1ff 100644
--- a/gns3server/api/routes/controller/privileges.py
+++ b/gns3server/api/routes/controller/privileges.py
@@ -16,6 +16,7 @@ API route for privileges
 """
 
 from typing import List
+import gns3server.db.models as models
 from gns3server.db.repositories.rbac import RbacRepository
 from .dependencies.database import get_repository
 from fastapi import APIRouter, Depends
@@ -33,7 +34,7 @@ router = APIRouter()
 )
 async def get_privileges(
     rbac_repo: RbacRepository = Depends(get_repository(RbacRepository)),
-) -> List[schemas.Privilege]:
+) -> List[models.Privilege]:
     """
     Get all privileges.
 
diff --git a/gns3server/api/routes/controller/roles.py b/gns3server/api/routes/controller/roles.py
index aab6e5a00..3f6e854a1 100644
--- a/gns3server/api/routes/controller/roles.py
+++ b/gns3server/api/routes/controller/roles.py
@@ -21,7 +21,7 @@ API routes for roles.
 
 from fastapi import APIRouter, Depends, status
 from uuid import UUID
-from typing import List
+from typing import List, Optional
 
 from gns3server import schemas
 from gns3server.controller.controller_error import (
@@ -31,6 +31,7 @@ from gns3server.controller.controller_error import (
     ControllerForbiddenError,
 )
 
+import gns3server.db.models as models
 from gns3server.db.repositories.rbac import RbacRepository
 from .dependencies.database import get_repository
 from .dependencies.rbac import has_privilege
@@ -43,7 +44,7 @@ router = APIRouter()
 
 
 @router.get("", response_model=List[schemas.Role], dependencies=[Depends(has_privilege("Role.Audit"))])
-async def get_roles(rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))) -> List[schemas.Role]:
+async def get_roles(rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))) -> List[models.Role]:
     """
     Get all roles.
 
@@ -61,7 +62,7 @@ async def get_roles(rbac_repo: RbacRepository = Depends(get_repository(RbacRepos
 )
 async def create_role(
     role_create: schemas.RoleCreate, rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))
-) -> schemas.Role:
+) -> Optional[models.Role]:
     """
     Create a new role.
 
@@ -78,7 +79,7 @@ async def create_role(
 async def get_role(
     role_id: UUID,
     rbac_repo: RbacRepository = Depends(get_repository(RbacRepository)),
-) -> schemas.Role:
+) -> models.Role:
     """
     Get a role.
 
@@ -94,7 +95,7 @@ async def get_role(
 @router.put("/{role_id}", response_model=schemas.Role, dependencies=[Depends(has_privilege("Role.Modify"))])
 async def update_role(
     role_id: UUID, role_update: schemas.RoleUpdate, rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))
-) -> schemas.Role:
+) -> Optional[models.Role]:
     """
     Update a role.
 
@@ -142,7 +143,7 @@ async def delete_role(
 )
 async def get_role_privileges(
     role_id: UUID, rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))
-) -> List[schemas.Privilege]:
+) -> List[models.Privilege]:
     """
     Get all role privileges.
 
diff --git a/gns3server/api/routes/controller/snapshots.py b/gns3server/api/routes/controller/snapshots.py
index f85b5d9ef..4ec8c467c 100644
--- a/gns3server/api/routes/controller/snapshots.py
+++ b/gns3server/api/routes/controller/snapshots.py
@@ -24,7 +24,7 @@ import logging
 log = logging.getLogger()
 
 from fastapi import APIRouter, Depends, status
-from typing import List
+from typing import Any, List
 from uuid import UUID
 
 from gns3server.controller.project import Project
@@ -35,7 +35,9 @@ from gns3server.controller import Controller
 from .dependencies.database import get_repository
 from .dependencies.rbac import has_privilege
 
-responses = {404: {"model": schemas.ErrorMessage, "description": "Could not find project or snapshot"}}
+responses: dict[int | str, dict[str, Any]] = {
+    404: {"model": schemas.ErrorMessage, "description": "Could not find project or snapshot"}
+}
 
 router = APIRouter(responses=responses)
 
diff --git a/gns3server/controller/topology.py b/gns3server/controller/topology.py
index 5048be4ce..f2390930a 100644
--- a/gns3server/controller/topology.py
+++ b/gns3server/controller/topology.py
@@ -53,7 +53,7 @@ GNS3_FILE_FORMAT_REVISION = 10
 
 
 class DynamipsNodeValidation(DynamipsCreate):
-    name: Optional[str] = None
+    name: Optional[str] = None  # type: ignore[assignment]
 
 
 def _check_topology_schema(topo, path):
diff --git a/gns3server/schemas/compute/atm_switch_nodes.py b/gns3server/schemas/compute/atm_switch_nodes.py
index 9a9db0845..9d126bfe9 100644
--- a/gns3server/schemas/compute/atm_switch_nodes.py
+++ b/gns3server/schemas/compute/atm_switch_nodes.py
@@ -26,8 +26,8 @@ class ATMSwitchBase(BaseModel):
     Common ATM switch properties.
     """
 
-    name: str = None
-    node_id: UUID = None
+    name: Optional[str] = None
+    node_id: Optional[UUID] = None
     usage: Optional[str] = None
     mappings: Optional[dict] = None
 
diff --git a/gns3server/schemas/compute/dynamips_nodes.py b/gns3server/schemas/compute/dynamips_nodes.py
index d01020a28..6292b400b 100644
--- a/gns3server/schemas/compute/dynamips_nodes.py
+++ b/gns3server/schemas/compute/dynamips_nodes.py
@@ -124,7 +124,6 @@ class DynamipsBase(BaseModel):
     node_id: Optional[UUID] = None
     name: Optional[str] = None
     dynamips_id: Optional[int] = Field(None, description="Dynamips internal ID")
-    platform: Optional[DynamipsPlatform] = Field(None, description="Cisco router platform")
     ram: Optional[int] = Field(None, gt=0, description="Amount of RAM in MB")
     nvram: Optional[int] = Field(None, gt=0, description="Amount of NVRAM in KB")
     image: Optional[str] = Field(None, description="Path to the IOS image")
@@ -185,11 +184,12 @@ class DynamipsUpdate(DynamipsBase):
     Properties to update a Dynamips node.
     """
 
-    pass
+    platform: Optional[DynamipsPlatform] = Field(None, description="Cisco router platform")
 
 
 class Dynamips(DynamipsBase):
     name: str
+    platform: Optional[DynamipsPlatform] = Field(None, description="Cisco router platform")
     node_id: UUID
     project_id: UUID
     dynamips_id: int
diff --git a/gns3server/schemas/compute/nat_nodes.py b/gns3server/schemas/compute/nat_nodes.py
index 95a703320..e3c569251 100644
--- a/gns3server/schemas/compute/nat_nodes.py
+++ b/gns3server/schemas/compute/nat_nodes.py
@@ -89,7 +89,7 @@ class NATBase(BaseModel):
     Common NAT node properties.
     """
 
-    name: str
+    name: Optional[str] = None
     node_id: Optional[UUID] = None
     usage: Optional[str] = None
     ports_mapping: Optional[List[Union[EthernetPort, TAPPort, UDPPort]]] = Field(
@@ -102,7 +102,7 @@ class NATCreate(NATBase):
     Properties to create a NAT node.
     """
 
-    pass
+    name: str
 
 
 class NATUpdate(NATBase):
@@ -110,10 +110,11 @@ class NATUpdate(NATBase):
     Properties to update a NAT node.
     """
 
-    name: Optional[str] = None
+    pass
 
 
 class NAT(NATBase):
+    name: str
     project_id: UUID
     node_id: UUID
     ports_mapping: List[Union[EthernetPort, TAPPort, UDPPort]]
diff --git a/gns3server/utils/encryption.py b/gns3server/utils/encryption.py
index 1f95f497b..38719a60e 100644
--- a/gns3server/utils/encryption.py
+++ b/gns3server/utils/encryption.py
@@ -48,7 +48,7 @@ def init_encryption(secrets_dir: str) -> None:
             os.makedirs(secrets_dir, exist_ok=True)
             with open(encryption_key_path, "w", encoding="utf-8") as f:
                 # Use Fernet's base64-encoded key format
-                f.write(key.decode() if isinstance(key, bytes) else key)
+                f.write(key.decode())
             # Set restrictive permissions (owner read/write only)
             os.chmod(encryption_key_path, 0o600)
         except OSError as e:
@@ -58,7 +58,7 @@ def init_encryption(secrets_dir: str) -> None:
     try:
         with open(encryption_key_path, encoding="utf-8") as f:
             key_content = f.read().strip()
-        key_bytes = key_content.encode() if isinstance(key_content, str) else key_content
+        key_bytes = key_content.encode()
         _fernet = Fernet(key_bytes)
         log.debug("Encryption initialized successfully")
     except OSError as e:
diff --git a/gns3server/utils/images.py b/gns3server/utils/images.py
index c06e22bec..06b4ae9be 100644
--- a/gns3server/utils/images.py
+++ b/gns3server/utils/images.py
@@ -126,7 +126,7 @@ def get_builtin_disks() -> List[str]:
     return builtin_disks
 
 
-async def read_image_info(path: str, expected_image_type: str = None) -> dict:
+async def read_image_info(path: str, expected_image_type: str | None = None) -> dict:
 
     header_magic_len = 7
     try:
@@ -155,7 +155,7 @@ async def read_image_info(path: str, expected_image_type: str = None) -> dict:
     return image_info
 
 
-async def discover_images(image_type: str, skip_image_paths: list = None) -> List[dict]:
+async def discover_images(image_type: str, skip_image_paths: list | None = None) -> List[dict]:
     """
     Scan directories for available images
     """
@@ -378,9 +378,9 @@ async def write_image(
                 f"File '{image_path}' already exists, please choose a different name or remove the existing image"
             )
 
-        checksum = checksum.hexdigest()
+        checksum_hex = checksum.hexdigest()
         image_dir = os.path.dirname(image_path)
-        duplicate_image = await images_repo.get_image_by_checksum(checksum, image_dir)
+        duplicate_image = await images_repo.get_image_by_checksum(checksum_hex, image_dir)
         if duplicate_image:
             raise InvalidImageError(
                 f"Image '{duplicate_image.filename}' with the same checksum already exists in '{image_dir}'"
@@ -396,5 +396,5 @@ async def write_image(
             log.warning(f"Could not remove '{tmp_path}'")
 
     return await images_repo.add_image(
-        image_name, image_type, image_size, image_path, checksum, checksum_algorithm="md5"
+        image_name, image_type, image_size, image_path, checksum_hex, checksum_algorithm="md5"
     )
diff --git a/gns3server/utils/packet_filter_validation.py b/gns3server/utils/packet_filter_validation.py
index cc2634546..1b9481ffd 100644
--- a/gns3server/utils/packet_filter_validation.py
+++ b/gns3server/utils/packet_filter_validation.py
@@ -15,7 +15,7 @@ class FilterValidationError(Exception):
     pass
 
 
-def validate_bpf_syntax(bpf_expression: str) -> Dict[str, Optional[str]]:
+def validate_bpf_syntax(bpf_expression: str) -> Dict[str, Any]:
     """
     Validate BPF filter expression syntax using tcpdump.
 
@@ -78,7 +78,7 @@ def validate_filter_parameters(filter_type: str, values: List[Any]) -> None:
     """
 
     # Define validation rules based on ubridge implementation
-    VALIDATION_RULES = {
+    VALIDATION_RULES: Dict[str, Dict[str, Any]] = {
         "frequency_drop": {
             "params_count": 1,
             "ranges": [(-1, 32767)],  # min, max
@@ -173,11 +173,11 @@ def filter_inactive_filters(filters: Dict[str, List[Any]]) -> Dict[str, List[Any
 
     active_filters = {}
     for filter_type, values in filters.items():
-        if not values or (isinstance(values, list) and len(values) == 0):
+        if not values:
             continue
 
         # Normalize values (strip strings, convert to int)
-        normalized_values = []
+        normalized_values: List[Any] = []
         for value in values:
             if isinstance(value, str):
                 normalized_values.append(value.strip("\n "))
@@ -228,7 +228,7 @@ def validate_all_filters(filters: Dict[str, List[Any]]) -> None:
         return
 
     for filter_type, values in filters.items():
-        if not values or (isinstance(values, list) and len(values) == 0):
+        if not values:
             continue
 
         validate_filter_parameters(filter_type, values)
diff --git a/pyproject.toml b/pyproject.toml
index 5a022c067..bb1f95c75 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -294,63 +294,18 @@ enable_error_code = ["ignore-without-code", "redundant-expr", "truthy-bool"]
 # Baseline: modules with existing type errors (error count at baseline time).
 # Remove modules from this list one small PR at a time. Never add new ones.
 module = [
-  "gns3server.agent",  # 2
-  "gns3server.agent.gns3_copilot.agent.context_manager",  # 5
-  "gns3server.agent.gns3_copilot.agent.model_factory",  # 4
-  "gns3server.agent.gns3_copilot.chat_sessions_repository",  # 8
-  "gns3server.agent.gns3_copilot.gns3_client.api_handlers",  # 10
-  "gns3server.agent.gns3_copilot.gns3_client.connector_factory",  # 1
-  "gns3server.agent.gns3_copilot.gns3_client.project_inventory",  # 2
-  "gns3server.agent.gns3_copilot.skills.loader",  # 1
-  "gns3server.agent.gns3_copilot.skills.manager",  # 4
-  "gns3server.agent.gns3_copilot.tools_v2.config_tools_nornir",  # 6
-  "gns3server.agent.gns3_copilot.tools_v2.display_tools_nornir",  # 6
-  "gns3server.agent.gns3_copilot.tools_v2.gns3_packet_filter",  # 1
-  "gns3server.agent.gns3_copilot.tools_v2.gns3_start_node",  # 3
-  "gns3server.agent.gns3_copilot.tools_v2.gns3_stop_node",  # 3
-  "gns3server.agent.gns3_copilot.tools_v2.gns3_suspend_node",  # 3
-  "gns3server.agent.gns3_copilot.tools_v2.packet_analysis_tool",  # 1
-  "gns3server.agent.gns3_copilot.tools_v2.vpcs_tools_netmiko",  # 9
-  "gns3server.agent.gns3_copilot.utils.custom_netmiko.scripts.list_netmiko_telnet_devices",  # 1
-  "gns3server.agent.gns3_copilot.utils.message_converters",  # 2
-  "gns3server.agent.gns3_copilot.utils.parse_tool_content",  # 1
-  "gns3server.agent.mcp.appliances",  # 1
-  "gns3server.agent.web_wireshark.docker_client",  # 5
-  "gns3server.agent.web_wireshark.manage_wireshark",  # 1
-  "gns3server.agent.web_wireshark.manager",  # 9
-  "gns3server.agent.web_wireshark.stats",  # 4
-  "gns3server.api.routes.compute.atm_switch_nodes",  # 9
-  "gns3server.api.routes.compute.capabilities",  # 1
-  "gns3server.api.routes.compute.cloud_nodes",  # 14
-  "gns3server.api.routes.compute.compute",  # 1
-  "gns3server.api.routes.compute.dependencies.authentication",  # 3
-  "gns3server.api.routes.compute.docker_nodes",  # 26
-  "gns3server.api.routes.compute.dynamips_nodes",  # 9
-  "gns3server.api.routes.compute.ethernet_hub_nodes",  # 9
-  "gns3server.api.routes.compute.ethernet_switch_nodes",  # 16
-  "gns3server.api.routes.compute.frame_relay_switch_nodes",  # 9
-  "gns3server.api.routes.compute.iou_nodes",  # 15
-  "gns3server.api.routes.compute.nat_nodes",  # 10
-  "gns3server.api.routes.compute.notifications",  # 4
   "gns3server.api.routes.compute.vmware_nodes",  # 10
   "gns3server.api.routes.compute.vpcs_nodes",  # 9
   "gns3server.api.routes.controller.acl",  # 5
-  "gns3server.api.routes.controller.api_keys",  # 1
-  "gns3server.api.routes.controller.chat",  # 1
   "gns3server.api.routes.controller.computes",  # 6
   "gns3server.api.routes.controller.controller",  # 10
   "gns3server.api.routes.controller.dependencies.authentication",  # 11
   "gns3server.api.routes.controller.dependencies.database",  # 2
-  "gns3server.api.routes.controller.drawings",  # 1
   "gns3server.api.routes.controller.groups",  # 6
   "gns3server.api.routes.controller.images",  # 9
   "gns3server.api.routes.controller.llm_model_configs",  # 32
-  "gns3server.api.routes.controller.nodes",  # 13
   "gns3server.api.routes.controller.pools",  # 8
-  "gns3server.api.routes.controller.privileges",  # 1
   "gns3server.api.routes.controller.projects",  # 16
-  "gns3server.api.routes.controller.roles",  # 5
-  "gns3server.api.routes.controller.snapshots",  # 1
   "gns3server.api.routes.controller.templates",  # 10
   "gns3server.api.routes.controller.users",  # 14
   "gns3server.api.server",  # 2
@@ -362,7 +317,6 @@ module = [
   "gns3server.controller.appliance",  # 2
   "gns3server.controller.appliance_manager",  # 5
   "gns3server.controller.project",  # 2
-  "gns3server.controller.topology",  # 1
   "gns3server.db.repositories.api_keys",  # 8
   "gns3server.db.repositories.computes",  # 10
   "gns3server.db.repositories.images",  # 14
@@ -372,13 +326,10 @@ module = [
   "gns3server.db.repositories.templates",  # 6
   "gns3server.db.repositories.users",  # 12
   "gns3server.db.tasks",  # 12
-  "gns3server.schemas.compute.atm_switch_nodes",  # 5
   "gns3server.schemas.compute.cloud_nodes",  # 1
   "gns3server.schemas.compute.docker_nodes",  # 2
-  "gns3server.schemas.compute.dynamips_nodes",  # 1
   "gns3server.schemas.compute.frame_relay_switch_nodes",  # 5
   "gns3server.schemas.compute.iou_nodes",  # 3
-  "gns3server.schemas.compute.nat_nodes",  # 1
   "gns3server.schemas.compute.qemu_nodes",  # 1
   "gns3server.schemas.compute.virtualbox_nodes",  # 2
   "gns3server.schemas.compute.vmware_nodes",  # 3
@@ -396,10 +347,7 @@ module = [
   "gns3server.services.computes",  # 4
   "gns3server.services.templates",  # 18
   "gns3server.utils.asyncio.aiozipstream",  # 8
-  "gns3server.utils.encryption",  # 2
   "gns3server.utils.http_client",  # 4
-  "gns3server.utils.images",  # 4
-  "gns3server.utils.packet_filter_validation",  # 16
   "gns3server.utils.websocket_to_websocket",  # 12
   "gns3server.utils.zipfile_zstd._patcher",  # 1
 ]