fix: make tool registry reads thread-safe

tests/tools/test_registry.py

@@ -1,6 +1,7 @@
 """Tests for the central tool registry."""
 
 import json
+import threading
 
 from tools.registry import ToolRegistry
 
@@ -167,6 +168,32 @@ class TestToolsetAvailability:
         )
         assert reg.get_all_tool_names() == ["a_tool", "z_tool"]
 
+    def test_get_registered_toolset_names(self):
+        reg = ToolRegistry()
+        reg.register(
+            name="first", toolset="zeta", schema=_make_schema(), handler=_dummy_handler
+        )
+        reg.register(
+            name="second", toolset="alpha", schema=_make_schema(), handler=_dummy_handler
+        )
+        reg.register(
+            name="third", toolset="alpha", schema=_make_schema(), handler=_dummy_handler
+        )
+        assert reg.get_registered_toolset_names() == ["alpha", "zeta"]
+
+    def test_get_tool_names_for_toolset(self):
+        reg = ToolRegistry()
+        reg.register(
+            name="z_tool", toolset="grouped", schema=_make_schema(), handler=_dummy_handler
+        )
+        reg.register(
+            name="a_tool", toolset="grouped", schema=_make_schema(), handler=_dummy_handler
+        )
+        reg.register(
+            name="other_tool", toolset="other", schema=_make_schema(), handler=_dummy_handler
+        )
+        assert reg.get_tool_names_for_toolset("grouped") == ["a_tool", "z_tool"]
+
     def test_handler_exception_returns_error(self):
         reg = ToolRegistry()
 
@@ -301,6 +328,22 @@ class TestEmojiMetadata:
         assert reg.get_emoji("t") == "⚡"
 
 
+class TestEntryLookup:
+    def test_get_entry_returns_registered_entry(self):
+        reg = ToolRegistry()
+        reg.register(
+            name="alpha", toolset="core", schema=_make_schema("alpha"), handler=_dummy_handler
+        )
+        entry = reg.get_entry("alpha")
+        assert entry is not None
+        assert entry.name == "alpha"
+        assert entry.toolset == "core"
+
+    def test_get_entry_returns_none_for_unknown_tool(self):
+        reg = ToolRegistry()
+        assert reg.get_entry("missing") is None
+
+
 class TestSecretCaptureResultContract:
     def test_secret_request_result_does_not_include_secret_value(self):
         result = {
@@ -309,3 +352,141 @@ class TestSecretCaptureResultContract:
             "validated": False,
         }
         assert "secret" not in json.dumps(result).lower()
+
+
+class TestThreadSafety:
+    def test_get_available_toolsets_uses_coherent_snapshot(self, monkeypatch):
+        reg = ToolRegistry()
+        reg.register(
+            name="alpha",
+            toolset="gated",
+            schema=_make_schema("alpha"),
+            handler=_dummy_handler,
+            check_fn=lambda: False,
+        )
+
+        entries, toolset_checks = reg._snapshot_state()
+
+        def snapshot_then_mutate():
+            reg.deregister("alpha")
+            return entries, toolset_checks
+
+        monkeypatch.setattr(reg, "_snapshot_state", snapshot_then_mutate)
+
+        toolsets = reg.get_available_toolsets()
+        assert toolsets["gated"]["available"] is False
+        assert toolsets["gated"]["tools"] == ["alpha"]
+
+    def test_check_tool_availability_tolerates_concurrent_register(self):
+        reg = ToolRegistry()
+        check_started = threading.Event()
+        writer_done = threading.Event()
+        errors = []
+        result_holder = {}
+        writer_completed_during_check = {}
+
+        def blocking_check():
+            check_started.set()
+            writer_completed_during_check["value"] = writer_done.wait(timeout=1)
+            return True
+
+        reg.register(
+            name="alpha",
+            toolset="gated",
+            schema=_make_schema("alpha"),
+            handler=_dummy_handler,
+            check_fn=blocking_check,
+        )
+        reg.register(
+            name="beta",
+            toolset="plain",
+            schema=_make_schema("beta"),
+            handler=_dummy_handler,
+        )
+
+        def reader():
+            try:
+                result_holder["value"] = reg.check_tool_availability()
+            except Exception as exc:  # pragma: no cover - exercised on failure only
+                errors.append(exc)
+
+        def writer():
+            assert check_started.wait(timeout=1)
+            reg.register(
+                name="gamma",
+                toolset="new",
+                schema=_make_schema("gamma"),
+                handler=_dummy_handler,
+            )
+            writer_done.set()
+
+        reader_thread = threading.Thread(target=reader)
+        writer_thread = threading.Thread(target=writer)
+        reader_thread.start()
+        writer_thread.start()
+        reader_thread.join(timeout=2)
+        writer_thread.join(timeout=2)
+
+        assert not reader_thread.is_alive()
+        assert not writer_thread.is_alive()
+        assert writer_completed_during_check["value"] is True
+        assert errors == []
+
+        available, unavailable = result_holder["value"]
+        assert "gated" in available
+        assert "plain" in available
+        assert unavailable == []
+
+    def test_get_available_toolsets_tolerates_concurrent_deregister(self):
+        reg = ToolRegistry()
+        check_started = threading.Event()
+        writer_done = threading.Event()
+        errors = []
+        result_holder = {}
+        writer_completed_during_check = {}
+
+        def blocking_check():
+            check_started.set()
+            writer_completed_during_check["value"] = writer_done.wait(timeout=1)
+            return True
+
+        reg.register(
+            name="alpha",
+            toolset="gated",
+            schema=_make_schema("alpha"),
+            handler=_dummy_handler,
+            check_fn=blocking_check,
+        )
+        reg.register(
+            name="beta",
+            toolset="plain",
+            schema=_make_schema("beta"),
+            handler=_dummy_handler,
+        )
+
+        def reader():
+            try:
+                result_holder["value"] = reg.get_available_toolsets()
+            except Exception as exc:  # pragma: no cover - exercised on failure only
+                errors.append(exc)
+
+        def writer():
+            assert check_started.wait(timeout=1)
+            reg.deregister("beta")
+            writer_done.set()
+
+        reader_thread = threading.Thread(target=reader)
+        writer_thread = threading.Thread(target=writer)
+        reader_thread.start()
+        writer_thread.start()
+        reader_thread.join(timeout=2)
+        writer_thread.join(timeout=2)
+
+        assert not reader_thread.is_alive()
+        assert not writer_thread.is_alive()
+        assert writer_completed_during_check["value"] is True
+        assert errors == []
+
+        toolsets = result_holder["value"]
+        assert "gated" in toolsets
+        assert toolsets["gated"]["available"] is True