feat(steering): opt-in cat redirection steering for shell tools

Add CatFileEditsSteeringPolicy to UnifiedSteeringHandler to intercept shell execution when the normalized command uses cat > / cat >> for file create/append, with a fixed steering message.

Wire opt-in via session/tool_call_reactor config, JSON schemas, sample env, CLI --enable-cat-file-edits-steering, and CAT_FILE_EDITS_STEERING_* env vars (from_env_part1b).

Recognize run_terminal_cmd as a shell tool in ShellExecutionTools and CommandExtractionService.

Tests: policy unit tests, CLI wiring, reactor policy ordering; schema drift fixture updated.

Docs: cli-parameters and configuration examples.

Note: tests/unit/core/cli_support/applicators/test_session_applicator.py left unstaged (working tree had broad CRLF-only churn); Namespace still tolerates missing cat_file_edits_steering_enabled via getattr in SessionApplicator.
Made-with: Cursor

Author: Mateusz

config/config.example.yaml

@@ -109,6 +109,9 @@ session:
   # Tool call reactor steering for pytest full-suite runs (requires opt-in)
   pytest_full_suite_steering_enabled: false
 
+  # Steering for shell commands using cat > / cat >> to create or append files (opt-in)
+  cat_file_edits_steering_enabled: false
+
   # Test execution reminder system
   # Tracks file modifications and test executions, reminding agents to run tests
   # before completing tasks when code changes haven't been verified.

config/sample.env

@@ -96,6 +96,10 @@ APPLY_DIFF_STEERING_ENABLED=true
 APPLY_DIFF_STEERING_RATE_LIMIT_SECONDS=60
 # Enable steering that warns before running the entire pytest suite (opt-in)
 PYTEST_FULL_SUITE_STEERING_ENABLED=false
+# Steering for cat > / cat >> file create-append via shell (opt-in)
+CAT_FILE_EDITS_STEERING_ENABLED=false
+# Optional custom message:
+# CAT_FILE_EDITS_STEERING_MESSAGE=
 
 # Binary File Edit Steering Settings
 # Detects and warns when agents attempt to edit binary files (executables, media, databases, etc.)

config/schemas/app_config.schema.yaml

@@ -227,6 +227,8 @@ properties:
       dangerous_command_steering_message: { type: ["string", "null"] }
       pytest_full_suite_steering_enabled: { type: boolean }
       pytest_full_suite_steering_message: { type: ["string", "null"] }
+      cat_file_edits_steering_enabled: { type: boolean }
+      cat_file_edits_steering_message: { type: ["string", "null"] }
       test_execution_reminder_enabled: { type: boolean }
       test_execution_reminder_message: { type: ["string", "null"] }
       fix_think_tags_enabled: { type: boolean }
@@ -310,6 +312,8 @@ properties:
           apply_diff_steering_message: { type: ["string", "null"] }
           pytest_full_suite_steering_enabled: { type: boolean }
           pytest_full_suite_steering_message: { type: ["string", "null"] }
+          cat_file_edits_steering_enabled: { type: boolean }
+          cat_file_edits_steering_message: { type: ["string", "null"] }
           inline_python_steering_enabled: { type: boolean }
           inline_python_steering_message: { type: ["string", "null"] }
           binary_file_edit_steering_enabled: { type: boolean }

config/schemas/tool_call_reactor_config.schema.yaml

@@ -30,6 +30,12 @@ properties:
     type:
       - string
       - "null"
+  cat_file_edits_steering_enabled:
+    type: boolean
+  cat_file_edits_steering_message:
+    type:
+      - string
+      - "null"
   inline_python_steering_enabled:
     type: boolean
   inline_python_steering_message:

docs/user_guide/cli-parameters.md

@@ -379,10 +379,12 @@ When auto-enabled with no explicit model configured, the system defaults to `ope
 | :--- | :--- | :--- |
 | `--enable-pytest-full-suite-steering` | `PYTEST_FULL_SUITE_STEERING_ENABLED=true` | Enable steering for full pytest suite. |
 | `--disable-pytest-full-suite-steering` | `PYTEST_FULL_SUITE_STEERING_ENABLED=false` | Disable steering for full pytest suite. |
+| `--enable-cat-file-edits-steering` | `CAT_FILE_EDITS_STEERING_ENABLED=true` | Enable steering when shell commands use `cat >` / `cat >>` to create or append files. Default is off; there is no CLI disable flag (use config or `CAT_FILE_EDITS_STEERING_ENABLED=false`). |
 | `--enable-pytest-context-saving` | N/A | Enable context saving rewrites. |
 | `--test-execution-reminder-enabled` | `TEST_EXECUTION_REMINDER_ENABLED=true` | Enable test execution reminder. |
 | `--no-test-execution-reminder-enabled` | `TEST_EXECUTION_REMINDER_ENABLED=false` | Disable test execution reminder. |
 | N/A | `PYTEST_FULL_SUITE_STEERING_MESSAGE` | Custom steering message. |
+| N/A | `CAT_FILE_EDITS_STEERING_MESSAGE` | Custom steering message for `cat` redirection file edits. |
 | N/A | `TEST_EXECUTION_REMINDER_MESSAGE` | Custom reminder message. |
 
 ### Empty Response Handling

docs/user_guide/configuration.md

@@ -242,6 +242,8 @@ session:
   # Pytest Integration
   pytest_full_suite_steering_enabled: false
   pytest_full_suite_steering_message: null
+  cat_file_edits_steering_enabled: false
+  cat_file_edits_steering_message: null
   pytest_context_saving_enabled: false
   test_execution_reminder_enabled: false
   test_execution_reminder_message: null
@@ -292,6 +294,10 @@ session:
     apply_diff_steering_enabled: true
     apply_diff_steering_rate_limit_seconds: 60
     apply_diff_steering_message: null
+
+    # Opt-in: steer agents away from shell `cat >` / `cat >>` for file edits
+    cat_file_edits_steering_enabled: false
+    cat_file_edits_steering_message: null
 
     access_policies:           # List of access policies
       - name: "block-dangerous"
@@ -745,14 +751,14 @@ empty_response:
   enabled: true
   max_retries: 1
 
-# Model Name Rewrites
-model_aliases:
-  - pattern: "^gpt-4-(.*)"
-    replacement: "openai:gpt-4-\1"
-
-  # Weighted replacement with request-size guardrails
-  - pattern: "^coding$"
-    replacement: "[first,max_context=164000,weight=4]opencode-go:glm-5.1^[weight=2,max_context=128000]opencode-go:kimi-k2.5^openai:gpt-4o"
+# Model Name Rewrites
+model_aliases:
+  - pattern: "^gpt-4-(.*)"
+    replacement: "openai:gpt-4-\1"
+
+  # Weighted replacement with request-size guardrails
+  - pattern: "^coding$"
+    replacement: "[first,max_context=164000,weight=4]opencode-go:glm-5.1^[weight=2,max_context=128000]opencode-go:kimi-k2.5^openai:gpt-4o"
 
 # Reasoning Aliases (Shorthands)
 reasoning_aliases:

src/core/app/stages/steering.py

@@ -118,6 +118,7 @@ def _register_steering_policies(
         """Register steering policies as singletons."""
         from src.services.steering.policies import (
             BinaryFileEditPolicy,
+            CatFileEditsSteeringPolicy,
             InlinePythonPolicy,
             PytestFullSuitePolicy,
         )
@@ -165,6 +166,20 @@ def _register_steering_policies(
             ),
         )
 
+        # Register CatFileEditsSteeringPolicy (opt-in)
+        services.add_singleton(
+            CatFileEditsSteeringPolicy,
+            implementation_factory=lambda provider: CatFileEditsSteeringPolicy(
+                message=getattr(
+                    reactor_config, "cat_file_edits_steering_message", None
+                ),
+                enabled=getattr(
+                    reactor_config, "cat_file_edits_steering_enabled", False
+                ),
+                prompt_override_path=Path("config/prompts/steering_cat_file_edits.md"),
+            ),
+        )
+
         # Register ConfiguredRulesPolicy
         services.add_singleton(
             ConfiguredRulesPolicy,
@@ -251,6 +266,7 @@ def _register_unified_steering_handler(
         from src.services.steering import UnifiedSteeringHandler
         from src.services.steering.policies import (
             BinaryFileEditPolicy,
+            CatFileEditsSteeringPolicy,
             InlinePythonPolicy,
             PytestFullSuitePolicy,
         )
@@ -261,6 +277,7 @@ def handler_factory(provider: IServiceProvider) -> UnifiedSteeringHandler:
                 provider.get_required_service(InlinePythonPolicy),
                 provider.get_required_service(BinaryFileEditPolicy),
                 provider.get_required_service(PytestFullSuitePolicy),
+                provider.get_required_service(CatFileEditsSteeringPolicy),
                 provider.get_required_service(ConfiguredRulesPolicy),
             ]
 

src/core/cli_support/applicators/session_applicator.py

@@ -385,6 +385,22 @@ def _apply_pytest_settings(
                 origin="--enable/disable-pytest-full-suite-steering",
             )
 
+        if getattr(args, "cat_file_edits_steering_enabled", None) is not None:
+            session = overrides.setdefault("session", {})
+            session["cat_file_edits_steering_enabled"] = (
+                args.cat_file_edits_steering_enabled
+            )
+            tool_call_reactor = session.setdefault("tool_call_reactor", {})
+            tool_call_reactor["cat_file_edits_steering_enabled"] = (
+                args.cat_file_edits_steering_enabled
+            )
+            resolution.record(
+                "session.cat_file_edits_steering_enabled",
+                args.cat_file_edits_steering_enabled,
+                ParameterSource.CLI,
+                origin="--enable-cat-file-edits-steering",
+            )
+
         if getattr(args, "disable_binary_file_edit_steering", None) is True:
             session = overrides.setdefault("session", {})
             tool_call_reactor = session.setdefault("tool_call_reactor", {})

src/core/cli_support/argument_parser_builder.py

@@ -1168,6 +1168,15 @@ def _add_pytest_arguments(self, parser: argparse.ArgumentParser) -> None:
             help="Disable steering for full pytest suite commands (overrides config)",
         )
 
+        parser.add_argument(
+            "--enable-cat-file-edits-steering",
+            action="store_const",
+            const=True,
+            dest="cat_file_edits_steering_enabled",
+            default=None,
+            help="Enable steering for shell commands using cat > / cat >> to edit files (overrides config; off by default)",
+        )
+
         # Pytest context saving
         parser.add_argument(
             "--enable-pytest-context-saving",

src/core/config/env/from_env_part1b.py

@@ -80,30 +80,30 @@ def _optional_int(value: str) -> int | None:
             path="session.project_dir_resolution_model",
             resolution=resolution,
         ),
-        "project_dir_resolution_mode": _get_env_value(
-            env,
-            "PROJECT_DIR_RESOLUTION_MODE",
-            "hybrid",
-            path="session.project_dir_resolution_mode",
-            resolution=resolution,
-        ),
-        "project_dir_resolution_filesystem_mode": _get_env_value(
-            env,
-            "PROJECT_DIR_RESOLUTION_FILESYSTEM_MODE",
-            "auto",
-            path="session.project_dir_resolution_filesystem_mode",
-            resolution=resolution,
-        ),
-        "disable_default_openrouter_project_dir_resolution_fallback": _env_to_bool(
-            "DISABLE_DEFAULT_OPENROUTER_PROJECT_DIR_RESOLUTION_FALLBACK",
-            False,
-            env,
-            path="session.disable_default_openrouter_project_dir_resolution_fallback",
-            resolution=resolution,
-        ),
-        "tool_call_repair_enabled": _env_to_bool(
-            "TOOL_CALL_REPAIR_ENABLED",
-            True,
+        "project_dir_resolution_mode": _get_env_value(
+            env,
+            "PROJECT_DIR_RESOLUTION_MODE",
+            "hybrid",
+            path="session.project_dir_resolution_mode",
+            resolution=resolution,
+        ),
+        "project_dir_resolution_filesystem_mode": _get_env_value(
+            env,
+            "PROJECT_DIR_RESOLUTION_FILESYSTEM_MODE",
+            "auto",
+            path="session.project_dir_resolution_filesystem_mode",
+            resolution=resolution,
+        ),
+        "disable_default_openrouter_project_dir_resolution_fallback": _env_to_bool(
+            "DISABLE_DEFAULT_OPENROUTER_PROJECT_DIR_RESOLUTION_FALLBACK",
+            False,
+            env,
+            path="session.disable_default_openrouter_project_dir_resolution_fallback",
+            resolution=resolution,
+        ),
+        "tool_call_repair_enabled": _env_to_bool(
+            "TOOL_CALL_REPAIR_ENABLED",
+            True,
             env,
             path="session.tool_call_repair_enabled",
             resolution=resolution,
@@ -167,6 +167,20 @@ def _optional_int(value: str) -> int | None:
             path="session.pytest_full_suite_steering_message",
             resolution=resolution,
         ),
+        "cat_file_edits_steering_enabled": _env_to_bool(
+            "CAT_FILE_EDITS_STEERING_ENABLED",
+            False,
+            env,
+            path="session.cat_file_edits_steering_enabled",
+            resolution=resolution,
+        ),
+        "cat_file_edits_steering_message": _get_env_value(
+            env,
+            "CAT_FILE_EDITS_STEERING_MESSAGE",
+            None,
+            path="session.cat_file_edits_steering_message",
+            resolution=resolution,
+        ),
         "test_execution_reminder_enabled": _env_to_bool(
             "TEST_EXECUTION_REMINDER_ENABLED",
             False,
@@ -195,21 +209,21 @@ def _optional_int(value: str) -> int | None:
             path="session.fix_think_tags_streaming_buffer_size",
             resolution=resolution,
         ),
-        "double_ampersand_fixes_for_windows_enabled": _env_to_bool(
-            "DOUBLE_AMPERSAND_FIXES_FOR_WINDOWS_ENABLED",
-            True,
-            env,
-            path="session.double_ampersand_fixes_for_windows_enabled",
-            resolution=resolution,
-        ),
-        "auto_continue_removal_enabled": _env_to_bool(
-            "AUTO_CONTINUE_REMOVAL_ENABLED",
-            True,
-            env,
-            path="session.auto_continue_removal_enabled",
-            resolution=resolution,
-        ),
-        "planning_phase": {
+        "double_ampersand_fixes_for_windows_enabled": _env_to_bool(
+            "DOUBLE_AMPERSAND_FIXES_FOR_WINDOWS_ENABLED",
+            True,
+            env,
+            path="session.double_ampersand_fixes_for_windows_enabled",
+            resolution=resolution,
+        ),
+        "auto_continue_removal_enabled": _env_to_bool(
+            "AUTO_CONTINUE_REMOVAL_ENABLED",
+            True,
+            env,
+            path="session.auto_continue_removal_enabled",
+            resolution=resolution,
+        ),
+        "planning_phase": {
             "enabled": _env_to_bool(
                 "PLANNING_PHASE_ENABLED",
                 False,