fix: improve cross-device evidence, request diagnostics and prompt efficiency

artemis/agents/validator/tool_declarations.py

@@ -257,7 +257,12 @@ REPORT_TASK_STATUS_TOOL = ToolDeclaration(
             },
             "explanation": {
                 "type": "string",
-                "description": "Provide the final explanation or summary of the task execution.",
+                "description": (
+                    "Provide the final answer. If the user requests a report or other written"
+                    " deliverable, include the actual content with all requested sections,"
+                    " observed findings, evidence and untested or blocked scope; a short"
+                    " completion notice is not a substitute. Do not invent missing evidence."
+                ),
             },
         },
         "required": ["status", "explanation"],