Improve Error Message for REST Tool Creation – Replace "Validation Failed" with Detailed Response (#675)

* tool

Signed-off-by: RAKHI DUTTA <[email protected]>

* tools

Signed-off-by: RAKHI DUTTA <[email protected]>

* main revert

Signed-off-by: RAKHI DUTTA <[email protected]>

* main revert

Signed-off-by: RAKHI DUTTA <[email protected]>

---------

Signed-off-by: RAKHI DUTTA <[email protected]>
Co-authored-by: RAKHI DUTTA <[email protected]>

Author: rakdutta

mcpgateway/utils/error_formatter.py

@@ -83,7 +83,7 @@ def format_validation_error(error: ValidationError) -> Dict[str, Any]:
             ...     result = ErrorFormatter.format_validation_error(e)
             <class 'pydantic_core._pydantic_core.ValidationError'>
             >>> result['message']
-            'Validation failed'
+            'Validation failed: Name must start with a letter and contain only letters, numbers, and underscores'
             >>> result['success']
             False
             >>> len(result['details']) > 0
@@ -134,7 +134,7 @@ def format_validation_error(error: ValidationError) -> Dict[str, Any]:
         # Log the full error for debugging
         logger.debug(f"Validation error: {error}")
 
-        return {"message": "Validation failed", "details": errors, "success": False}
+        return {"message": f"Validation failed: {user_message}", "details": errors, "success": False}
 
     @staticmethod
     def _get_user_message(field: str, technical_msg: str) -> str:

tests/unit/mcpgateway/utils/test_error_formatter.py

@@ -71,7 +71,7 @@ def test_format_validation_error_letter_requirement():
     with pytest.raises(ValidationError) as exc:
         NameModel(name="Bobby")
     result = ErrorFormatter.format_validation_error(exc.value)
-    assert result["message"] == "Validation failed"
+    assert result["message"] == "Validation failed: Name must start with a letter and contain only letters, numbers, and underscores"
     assert result["success"] is False
     assert result["details"][0]["field"] == "name"
     assert "must start with a letter" in result["details"][0]["message"]