From 168826a335f79f54781205b6854069830d8da28d Mon Sep 17 00:00:00 2001
From: Ian <ian@usestrix.com>
Date: Tue, 20 Oct 2026 19:16:45 -0400
Subject: [PATCH] feat(agents): let callers remove base tools from scan agents

---
 strix/agents/factory.py               |  7 +++++++
 tests/test_agent_tool_registration.py | 13 +++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/strix/agents/factory.py b/strix/agents/factory.py
index ca27e4f9a..4c9f81dac 100644
--- a/strix/agents/factory.py
+++ b/strix/agents/factory.py
@@ -670,6 +670,7 @@ _BASE_TOOLS: tuple[Tool, ...] = (
 # ``strix.runtime.backends.register_backend``: register before the first
 # ``build_strix_agent`` call and every agent (root + children) gets them.
 _EXTRA_TOOLS: list[Tool] = []
+_REMOVED_TOOL_NAMES: set[str] = set()
 
 
 def _ensure_unique_tool_names(tools: Sequence[Tool]) -> None:
@@ -703,6 +704,11 @@ def register_agent_tools(*tools: Tool) -> None:
         logger.info("Registered extra agent tool: %s", getattr(tool, "name", tool))
 
 
+def remove_agent_tools(*names: str) -> None:
+    """Leave these base tools out of every scan agent built afterwards."""
+    _REMOVED_TOOL_NAMES.update(names)
+
+
 def registered_agent_tools() -> tuple[Tool, ...]:
     """Return the currently registered scan-agent tools."""
     return tuple(_EXTRA_TOOLS)
@@ -760,6 +766,7 @@ def build_strix_agent(
         tools: list[Tool] = [*_BASE_TOOLS, *agent_tools, finish_tool]
     else:
         tools = [*_BASE_TOOLS, *agent_tools, agent_finish]
+    tools = [tool for tool in tools if tool.name not in _REMOVED_TOOL_NAMES]
     _ensure_unique_tool_names(tools)
     tools = [
         _with_bounded_result(_with_strictness(_with_coerced_arguments(tool), strict_tool_schemas))
diff --git a/tests/test_agent_tool_registration.py b/tests/test_agent_tool_registration.py
index e459670b0..822c0b7f6 100644
--- a/tests/test_agent_tool_registration.py
+++ b/tests/test_agent_tool_registration.py
@@ -31,11 +31,15 @@ def _tool(name: str) -> FunctionTool:
 @pytest.fixture(autouse=True)
 def _reset_registry() -> object:
     saved = list(factory._EXTRA_TOOLS)
+    saved_removed = set(factory._REMOVED_TOOL_NAMES)
     factory._EXTRA_TOOLS.clear()
+    factory._REMOVED_TOOL_NAMES.clear()
     try:
         yield
     finally:
         factory._EXTRA_TOOLS[:] = saved
+        factory._REMOVED_TOOL_NAMES.clear()
+        factory._REMOVED_TOOL_NAMES.update(saved_removed)
 
 
 def test_register_agent_tools_is_deduped() -> None:
@@ -93,6 +97,15 @@ def test_per_call_extra_tools_reject_duplicate_registered_names() -> None:
         factory.build_strix_agent(is_root=True, extra_tools=[_tool("same_name")])
 
 
+def test_removed_tools_are_left_out_of_root_and_child() -> None:
+    factory.remove_agent_tools("create_vulnerability_report")
+
+    for is_root in (True, False):
+        names = [t.name for t in factory.build_strix_agent(is_root=is_root).tools]
+        assert "create_vulnerability_report" not in names
+        assert "create_dependency_report" in names
+
+
 def test_instructions_override_is_used_verbatim() -> None:
     custom = "You are a scan agent. Follow the provided scope."