diff --git a/headroom/proxy/helpers.py b/headroom/proxy/helpers.py
index 1e299cbe1..29364ac0d 100644
--- a/headroom/proxy/helpers.py
+++ b/headroom/proxy/helpers.py
@@ -61,6 +61,7 @@ from headroom.proxy.tool_injection_config import (
     get_tool_tracker_max_sessions as _get_tool_tracker_max_sessions,
 )
 from headroom.proxy.tool_injection_tracker import SessionToolTracker as _SessionToolTracker
+from headroom.proxy.tool_name_policy import extract_tool_name
 
 if TYPE_CHECKING:
     import httpx
@@ -1965,19 +1966,7 @@ def _extract_tool_name(tool_definition: dict[str, Any]) -> str | None:
       * Anthropic native: ``{"type": "memory_20250818", "name": "memory"}``
       * OpenAI function: ``{"type": "function", "function": {"name": "memory_save", ...}}``
     """
-    name = tool_definition.get("name")
-    if isinstance(name, str) and name:
-        return name
-    fn = tool_definition.get("function")
-    if isinstance(fn, dict):
-        fn_name = fn.get("name")
-        if isinstance(fn_name, str) and fn_name:
-            return fn_name
-    # Native memory tool with no explicit name uses ``type`` as its identifier.
-    type_val = tool_definition.get("type")
-    if isinstance(type_val, str) and type_val:
-        return type_val
-    return None
+    return extract_tool_name(tool_definition)
 
 
 def apply_session_sticky_memory_tools(
diff --git a/headroom/proxy/tool_name_policy.py b/headroom/proxy/tool_name_policy.py
new file mode 100644
index 000000000..3716afbf5
--- /dev/null
+++ b/headroom/proxy/tool_name_policy.py
@@ -0,0 +1,22 @@
+"""Tool-definition name extraction policy used by proxy injection helpers."""
+
+from __future__ import annotations
+
+from typing import Any
+
+
+def extract_tool_name(tool_definition: dict[str, Any]) -> str | None:
+    """Extract a stable tool name from a tool definition."""
+
+    name = tool_definition.get("name")
+    if isinstance(name, str) and name:
+        return name
+    function_definition = tool_definition.get("function")
+    if isinstance(function_definition, dict):
+        function_name = function_definition.get("name")
+        if isinstance(function_name, str) and function_name:
+            return function_name
+    tool_type = tool_definition.get("type")
+    if isinstance(tool_type, str) and tool_type:
+        return tool_type
+    return None
diff --git a/tests/test_tool_name_policy.py b/tests/test_tool_name_policy.py
new file mode 100644
index 000000000..610f72193
--- /dev/null
+++ b/tests/test_tool_name_policy.py
@@ -0,0 +1,43 @@
+from __future__ import annotations
+
+from headroom.proxy.helpers import _extract_tool_name
+from headroom.proxy.tool_name_policy import extract_tool_name
+
+
+def test_extracts_anthropic_custom_tool_name() -> None:
+    assert extract_tool_name({"name": "memory_save"}) == "memory_save"
+
+
+def test_extracts_openai_function_tool_name() -> None:
+    assert (
+        extract_tool_name({"type": "function", "function": {"name": "memory_search"}})
+        == "memory_search"
+    )
+
+
+def test_extracts_native_tool_type_when_name_absent() -> None:
+    assert extract_tool_name({"type": "memory_20250818"}) == "memory_20250818"
+
+
+def test_prefers_explicit_name_over_function_and_type() -> None:
+    assert (
+        extract_tool_name(
+            {
+                "name": "headroom_retrieve",
+                "type": "function",
+                "function": {"name": "memory_save"},
+            }
+        )
+        == "headroom_retrieve"
+    )
+
+
+def test_ignores_empty_or_non_string_names() -> None:
+    assert extract_tool_name({"name": "", "function": {"name": ""}, "type": ""}) is None
+    assert extract_tool_name({"name": 123, "function": {"name": 456}, "type": []}) is None
+
+
+def test_helpers_private_wrapper_keeps_existing_import_path() -> None:
+    tool_definition = {"function": {"name": "memory_update"}}
+
+    assert _extract_tool_name(tool_definition) == extract_tool_name(tool_definition)