Fix critical import error and type-checker issues

- Fix ToolUsageErrorException import in tool_utils.py (renamed to ToolUsageError)
- Add proper type guards for fingerprint attribute access
- Fix CacheHandler.read() argument type conversion
- Resolve variable redefinition conflicts in _use method
- All type-checker errors now resolved (mypy passes)
- Import test passes successfully
- Core MCP tool output functionality verified working

Co-Authored-By: João <joao@crewai.com>

src/crewai/tools/tool_usage.py

@@ -8,7 +8,7 @@ from textwrap import dedent
 from typing import TYPE_CHECKING, Any, Union
 
 import json5
-from json_repair import repair_json
+from json_repair import repair_json  # type: ignore
 
 from crewai.agents.tools_handler import ToolsHandler
 from crewai.events.event_bus import crewai_event_bus
@@ -174,7 +174,7 @@ class ToolUsage:
                 "agent": self.agent,
             }
 
-            if self.agent.fingerprint:
+            if hasattr(self.agent, 'fingerprint') and self.agent.fingerprint:
                 event_data.update(self.agent.fingerprint)
             if self.task:
                 event_data["task_name"] = self.task.name or self.task.description
@@ -183,13 +183,14 @@ class ToolUsage:
 
         started_at = time.time()
         from_cache = False
-        result = None  # type: ignore
 
         if self.tools_handler and self.tools_handler.cache:
-            result = self.tools_handler.cache.read(
+            cache_result = self.tools_handler.cache.read(
-                tool=calling.tool_name, input=calling.arguments
+                tool=calling.tool_name, input=str(calling.arguments)
-            )  # type: ignore
+            )
-            from_cache = result is not None
+            from_cache = cache_result is not None
+            if cache_result is not None:
+                result = cache_result
 
         available_tool = next(
             (

src/crewai/utilities/tool_utils.py

@@ -1,24 +1,24 @@
-from typing import Any, Dict, List, Optional
+from typing import Any
 
 from crewai.agents.parser import AgentAction
 from crewai.security import Fingerprint
 from crewai.tools.structured_tool import CrewStructuredTool
 from crewai.tools.tool_types import ToolResult
-from crewai.tools.tool_usage import ToolUsage, ToolUsageErrorException
+from crewai.tools.tool_usage import ToolUsage, ToolUsageError
 from crewai.utilities.i18n import I18N
 
 
 def execute_tool_and_check_finality(
     agent_action: AgentAction,
-    tools: List[CrewStructuredTool],
+    tools: list[CrewStructuredTool],
     i18n: I18N,
-    agent_key: Optional[str] = None,
+    agent_key: str | None = None,
-    agent_role: Optional[str] = None,
+    agent_role: str | None = None,
-    tools_handler: Optional[Any] = None,
+    tools_handler: Any | None = None,
-    task: Optional[Any] = None,
+    task: Any | None = None,
-    agent: Optional[Any] = None,
+    agent: Any | None = None,
-    function_calling_llm: Optional[Any] = None,
+    function_calling_llm: Any | None = None,
-    fingerprint_context: Optional[Dict[str, str]] = None,
+    fingerprint_context: dict[str, str] | None = None,
 ) -> ToolResult:
     """Execute a tool and check if the result should be treated as a final answer.
 
@@ -50,7 +50,7 @@ def execute_tool_and_check_finality(
                             fingerprint_obj = Fingerprint.from_dict(fingerprint_context)
                             agent.set_fingerprint(fingerprint_obj)
                         except Exception as e:
-                            raise ValueError(f"Failed to set fingerprint: {e}")
+                            raise ValueError(f"Failed to set fingerprint: {e}") from e
 
         # Create tool usage instance
         tool_usage = ToolUsage(
@@ -65,7 +65,7 @@ def execute_tool_and_check_finality(
         # Parse tool calling
         tool_calling = tool_usage.parse_tool_calling(agent_action.text)
 
-        if isinstance(tool_calling, ToolUsageErrorException):
+        if isinstance(tool_calling, ToolUsageError):
             return ToolResult(tool_calling.message, False)
 
         # Check if tool name matches