diff --git a/backend/src/temporal/manager.py b/backend/src/temporal/manager.py
index 9aa075f..c6e3f77 100644
--- a/backend/src/temporal/manager.py
+++ b/backend/src/temporal/manager.py
@@ -186,13 +186,17 @@ class TemporalManager:
         # The workflow parameters are passed as individual positional args
         workflow_args = [target_id]
 
+        # Filter out metadata-only parameters (target_path, volume_mode)
+        # These are used by the system but NOT passed to the workflow
+        metadata_only_params = {"target_path", "volume_mode"}
+
         # Add parameters in order based on workflow signature
         # For security_assessment: scanner_config, analyzer_config, reporter_config
         # For atheris_fuzzing: target_file, max_iterations, timeout_seconds
-        # Parameters come from metadata.yaml's default_parameters merged with user params
         if workflow_params:
-            # Add all parameter values as positional args
-            workflow_args.extend(workflow_params.values())
+            # Only add parameters that are NOT metadata-only
+            filtered_params = {k: v for k, v in workflow_params.items() if k not in metadata_only_params}
+            workflow_args.extend(filtered_params.values())
 
         # Determine task queue from workflow vertical
         vertical = workflow_info.metadata.get("vertical", "default")