Address PR review feedback for CLI model config

- Fix docstring arg order: match resume_session_id, cli_model_config
  parameter order in run_main signature
- Persist cli_model_config in TaskflowSession for deterministic resume:
  restored automatically on resume, can be explicitly overridden with
  --model-config
- Add TestCliModelConfigOverride test suite (6 tests) covering override
  precedence, resolution, session persistence, and resume behavior
- Add session-level tests for cli_model_config persistence and defaults

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: anticomputer

src/seclab_taskflow_agent/runner.py

@@ -501,8 +501,8 @@ async def run_main(
         taskflow_path: Taskflow module path, or None.
         cli_globals: Global variables from CLI.
         prompt: User prompt text.
-        cli_model_config: Model configuration module path, or None.
         resume_session_id: Session ID to resume from a checkpoint.
+        cli_model_config: Model configuration module path, or None.
     """
     from .session import TaskflowSession
 
@@ -545,6 +545,9 @@ async def on_handoff_hook(context: RunContextWrapper[TContext], agent: Agent[TCo
             cli_globals = session.cli_globals
             prompt = session.prompt
             last_mcp_tool_results = list(session.last_tool_results)
+            # Restore persisted model config unless explicitly overridden
+            if not cli_model_config and session.cli_model_config:
+                cli_model_config = session.cli_model_config
             await render_model_output(
                 f"** 🤖🔄 Resuming session {resume_session_id} from task {session.next_task_index}\n"
             )
@@ -578,6 +581,7 @@ async def on_handoff_hook(context: RunContextWrapper[TContext], agent: Agent[TCo
                 cli_globals=cli_globals,
                 prompt=prompt or "",
                 total_tasks=len(taskflow_doc.taskflow),
+                cli_model_config=cli_model_config or "",
             )
             session.save()
             await render_model_output(f"** 🤖📋 Session: {session.session_id}\n")

src/seclab_taskflow_agent/session.py

@@ -60,6 +60,9 @@ class TaskflowSession(BaseModel):
     finished: bool = False
     error: str = ""
 
+    # CLI model config override persisted for deterministic resume
+    cli_model_config: str = ""
+
     # Accumulated tool results carried across tasks (used by repeat_prompt)
     last_tool_results: list[str] = Field(default_factory=list)
 

tests/test_runner.py

@@ -278,9 +278,95 @@ def test_task_engine_keys_override_config(self):
 
 
 # ===================================================================
-# _build_prompts_to_run
+# CLI model config override
 # ===================================================================
 
+class TestCliModelConfigOverride:
+    """Tests for CLI model config overriding taskflow model_config_ref."""
+
+    def test_cli_overrides_taskflow_model_config(self):
+        """cli_model_config takes precedence over taskflow_doc.model_config_ref."""
+        taskflow_ref = "taskflow.models.default"
+        cli_ref = "cli.models.override"
+
+        # Simulate the override logic from run_main
+        model_config_ref = taskflow_ref
+        if cli_ref:
+            model_config_ref = cli_ref
+
+        assert model_config_ref == cli_ref
+
+    def test_taskflow_model_config_used_when_cli_absent(self):
+        """Taskflow model_config_ref is used when cli_model_config is None."""
+        taskflow_ref = "taskflow.models.default"
+        cli_ref = None
+
+        model_config_ref = taskflow_ref
+        if cli_ref:
+            model_config_ref = cli_ref
+
+        assert model_config_ref == taskflow_ref
+
+    def test_cli_model_config_resolves_via_available_tools(self):
+        """CLI-provided model config is resolved through _resolve_model_config."""
+        at = _mock_available_tools()
+        at.get_model_config.return_value = _make_model_config(
+            models={"fast": "gpt-4o-mini"},
+        )
+        keys, mdict, params, api_type, backend = _resolve_model_config(at, "cli.override.ref")
+        at.get_model_config.assert_called_once_with("cli.override.ref")
+        assert mdict == {"fast": "gpt-4o-mini"}
+
+    def test_cli_model_config_persisted_in_session(self):
+        """cli_model_config is stored in session for deterministic resume."""
+        from seclab_taskflow_agent.session import TaskflowSession
+
+        session = TaskflowSession(
+            taskflow_path="test.flow",
+            cli_model_config="cli.models.fast",
+        )
+        assert session.cli_model_config == "cli.models.fast"
+
+    def test_session_resume_restores_cli_model_config(self, tmp_path, monkeypatch):
+        """Resumed session restores cli_model_config when not overridden."""
+        monkeypatch.setattr("seclab_taskflow_agent.session.session_dir", lambda: tmp_path)
+        from seclab_taskflow_agent.session import TaskflowSession
+
+        session = TaskflowSession(
+            taskflow_path="test.flow",
+            cli_model_config="persisted.models.ref",
+        )
+        session.save()
+
+        loaded = TaskflowSession.load(session.session_id)
+
+        # Simulate the resume logic from run_main
+        cli_model_config = None  # not passed on resume
+        if not cli_model_config and loaded.cli_model_config:
+            cli_model_config = loaded.cli_model_config
+
+        assert cli_model_config == "persisted.models.ref"
+
+    def test_session_resume_cli_override_takes_precedence(self, tmp_path, monkeypatch):
+        """Explicit --model-config on resume overrides persisted value."""
+        monkeypatch.setattr("seclab_taskflow_agent.session.session_dir", lambda: tmp_path)
+        from seclab_taskflow_agent.session import TaskflowSession
+
+        session = TaskflowSession(
+            taskflow_path="test.flow",
+            cli_model_config="persisted.models.ref",
+        )
+        session.save()
+
+        loaded = TaskflowSession.load(session.session_id)
+
+        # Simulate the resume logic from run_main with explicit override
+        cli_model_config = "new.override.ref"
+        if not cli_model_config and loaded.cli_model_config:
+            cli_model_config = loaded.cli_model_config
+
+        assert cli_model_config == "new.override.ref"
+
 class TestBuildPromptsToRun:
     """Tests for _build_prompts_to_run (async, run via asyncio.run)."""
 

tests/test_session.py

@@ -78,6 +78,23 @@ def test_list_sessions(self, tmp_path, monkeypatch):
         assert s1.session_id in ids
         assert s2.session_id in ids
 
+    def test_cli_model_config_persisted(self, tmp_path, monkeypatch):
+        """cli_model_config is persisted and restored on load."""
+        monkeypatch.setattr("seclab_taskflow_agent.session.session_dir", lambda: tmp_path)
+        s = TaskflowSession(
+            taskflow_path="examples.taskflows.echo",
+            cli_model_config="custom.models.fast",
+        )
+        s.save()
+
+        loaded = TaskflowSession.load(s.session_id)
+        assert loaded.cli_model_config == "custom.models.fast"
+
+    def test_cli_model_config_defaults_empty(self):
+        """cli_model_config defaults to empty string."""
+        s = TaskflowSession(taskflow_path="test.flow")
+        assert s.cli_model_config == ""
+
 
 class TestCompletedTask:
     """Tests for CompletedTask model."""