diff --git a/backend/packages/harness/deerflow/community/youcom/tools.py b/backend/packages/harness/deerflow/community/youcom/tools.py
index d9ebc1bdb9..9dc3743019 100644
--- a/backend/packages/harness/deerflow/community/youcom/tools.py
+++ b/backend/packages/harness/deerflow/community/youcom/tools.py
@@ -25,8 +25,21 @@ Both endpoints return the same body — ``{"results": {"web": [...], "news":
 This module is self-contained (httpx only, no You.com SDK and no new
 dependency). Requests to You.com carry a ``User-Agent`` identifying DeerFlow so
 You.com can attribute integration traffic; it is sent only to You.com hosts.
+
+The tool is a coroutine and sends its request through ``httpx.AsyncClient``. A
+sync client would run the whole tool on the default executor and hold one of
+that pool's threads for the network round-trip, so several providers queried in
+parallel queued behind each other. Two things in this module read from disk,
+and both are resolved off the event loop: the tool config (which stats the
+config file) always runs on an executor thread, and the ``User-Agent`` (which
+reads the installed package metadata) does so on its first, cold call only.
+Later calls hit the in-memory cache and are read directly, so the hot path
+does not pay an executor round-trip for a string it already has.
+``backend/tests/blocking_io/test_youcom_search_async.py`` pins the result — the
+request is awaited on the loop thread, and neither disk read runs there.
 """
 
+import asyncio
 import json
 import logging
 import os
@@ -69,21 +82,42 @@ def _user_agent() -> str:
     return f"deerflow-harness/{harness_version} youdotcom-integration/bytedance-deer-flow"
 
 
-def _get_api_key(tool_name: str = "web_search") -> str | None:
-    """Resolve the You.com key from the tool's config block, then the env var.
+def _resolve_tool_settings(tool_name: str) -> tuple[str | None, object]:
+    """Resolve the API key and the configured `max_results` in one config read.
 
-    Returns None when neither is set, which is not an error here: the caller
-    falls back to the keyless endpoint.
+    Config resolution stats the config file, so callers must run this off the
+    agent event loop. Reading the key and the result count from a single
+    resolution keeps the tool from touching the config file twice per call.
+
+    The key is None when neither the config nor the environment sets one,
+    which is not an error here: the caller falls back to the keyless endpoint.
     """
     config = get_app_config().get_tool_config(tool_name)
+    max_results = None
+    api_key = None
     if config is not None:
-        api_key = (config.model_extra or {}).get("api_key")
-        if isinstance(api_key, str) and api_key.strip():
-            return api_key.strip()
-    env_key = os.getenv("YDC_API_KEY")
-    if isinstance(env_key, str) and env_key.strip():
-        return env_key.strip()
-    return None
+        extra = config.model_extra or {}
+        max_results = extra.get("max_results")
+        candidate = extra.get("api_key")
+        if isinstance(candidate, str) and candidate.strip():
+            api_key = candidate.strip()
+    if api_key is None:
+        env_key = os.getenv("YDC_API_KEY")
+        if isinstance(env_key, str) and env_key.strip():
+            api_key = env_key.strip()
+    return api_key, max_results
+
+
+async def _resolve_user_agent() -> str:
+    """Return the DeerFlow User-Agent, keeping the cold metadata read off the loop.
+
+    The first call reads the installed package metadata from disk, so it runs
+    on an executor thread. Every later call is an in-memory cache hit and is
+    read directly, so the hot path costs no executor round-trip.
+    """
+    if _user_agent.cache_info().currsize:
+        return _user_agent()
+    return await asyncio.to_thread(_user_agent)
 
 
 def _count_for_request(value: object) -> int:
@@ -100,17 +134,17 @@ def _count_for_request(value: object) -> int:
     )
 
 
-def _search(api_key: str | None, query: str, count: int) -> dict:
+async def _search(api_key: str | None, query: str, count: int) -> dict:
     """GET the keyed endpoint when a key is configured, else the keyless one."""
-    headers = {"Accept": "application/json", "User-Agent": _user_agent()}
+    headers = {"Accept": "application/json", "User-Agent": await _resolve_user_agent()}
     if api_key:
         endpoint = _YOUCOM_SEARCH_ENDPOINT
         headers["X-API-Key"] = api_key
     else:
         endpoint = _YOUCOM_KEYLESS_ENDPOINT
 
-    with httpx.Client(timeout=_TIMEOUT_S) as client:
-        response = client.get(endpoint, params={"query": query, "count": count}, headers=headers)
+    async with httpx.AsyncClient(timeout=_TIMEOUT_S) as client:
+        response = await client.get(endpoint, params={"query": query, "count": count}, headers=headers)
     response.raise_for_status()
     return response.json()
 
@@ -130,7 +164,7 @@ def _snippet(result: dict) -> str:
 
 
 @tool("web_search", parse_docstring=True)
-def web_search_tool(query: str, max_results: int | None = None) -> str:
+async def web_search_tool(query: str, max_results: int | None = None) -> str:
     """Search the web for information using You.com.
 
     Each result carries extracted snippets from the page, not just a meta
@@ -140,17 +174,15 @@ def web_search_tool(query: str, max_results: int | None = None) -> str:
         query: Search keywords describing what you want to find. Be specific for better results.
         max_results: Maximum number of search results to return. If omitted, uses the configured value (default 5). Clamped to 1-100.
     """
+    # Config resolution can read files; keep it off the event loop.
+    api_key, configured_max_results = await asyncio.to_thread(_resolve_tool_settings, "web_search")
     # Honor the caller-supplied max_results; fall back to config only when omitted.
     if max_results is None:
-        config = get_app_config().get_tool_config("web_search")
-        if config is not None:
-            max_results = (config.model_extra or {}).get("max_results")
+        max_results = configured_max_results
     count = _DEFAULT_MAX_RESULTS if max_results is None else _count_for_request(max_results)
 
-    api_key = _get_api_key("web_search")
-
     try:
-        data = _search(api_key, query, count)
+        data = await _search(api_key, query, count)
     except httpx.HTTPStatusError as e:
         status = e.response.status_code
         logger.error("You.com API returned HTTP %s: %s", status, e.response.text)
diff --git a/backend/tests/blocking_io/test_youcom_search_async.py b/backend/tests/blocking_io/test_youcom_search_async.py
new file mode 100644
index 0000000000..6221ed7854
--- /dev/null
+++ b/backend/tests/blocking_io/test_youcom_search_async.py
@@ -0,0 +1,159 @@
+"""The You.com community tool must not occupy an executor thread or block the loop.
+
+The You.com provider resolved its config and sent its search request through
+a synchronous ``httpx.Client``. A sync LangChain tool invoked through
+``ainvoke`` runs on the default executor, so the request held one of that
+pool's threads for the whole network round-trip: with several providers
+queried in parallel the default pool ran out of threads and the tool calls
+queued behind each other.
+
+The probes below assert the whole fix:
+
+* the request is awaited on the event loop thread instead of an executor
+  thread, so no pool thread is held for the round-trip;
+* the config lookup, which reads the config file, still runs off the loop.
+  The tool body is now a coroutine that executes on the loop, so a file read
+  left in it would block the loop; the strict blocking-I/O gate fails if the
+  lookup regresses onto the loop.
+* the request goes out through the async client. A `MockTransport` runs its
+  handler on the calling thread and performs no real blocking I/O, so a
+  provider that stayed async but sent the request through a sync
+  `httpx.Client` would satisfy the thread assertion above; the recorded
+  client factory is what catches that partial regression.
+"""
+
+import asyncio
+import threading
+from pathlib import Path
+from types import SimpleNamespace
+
+import httpx
+import pytest
+
+from deerflow.community.youcom import tools as youcom_tools
+
+pytestmark = pytest.mark.asyncio
+
+
+def _patch_transport(monkeypatch, request_threads: list[int], clients: list[str]) -> None:
+    """Answer every request locally and record the thread that served it.
+
+    The provider's module holds the shared ``httpx`` module, so the reference
+    itself is replaced with a namespace exposing both client factories. That
+    keeps the test hermetic — no request leaves the machine — whichever
+    factory the provider uses. Each factory records its name in ``clients``
+    so a test can assert which one the provider reached for.
+    """
+
+    def respond(request: httpx.Request) -> httpx.Response:
+        request_threads.append(threading.get_ident())
+        return httpx.Response(200, json={"results": {"web": []}})
+
+    transport = httpx.MockTransport(respond)
+
+    def async_client(**kwargs):
+        clients.append("AsyncClient")
+        return httpx.AsyncClient(transport=transport, **kwargs)
+
+    def sync_client(**kwargs):
+        clients.append("Client")
+        return httpx.Client(transport=transport, **kwargs)
+
+    monkeypatch.setattr(
+        youcom_tools,
+        "httpx",
+        SimpleNamespace(
+            AsyncClient=async_client,
+            Client=sync_client,
+            HTTPStatusError=httpx.HTTPStatusError,
+        ),
+    )
+
+
+def _patch_config(monkeypatch, load_config=None) -> None:
+    def config():
+        return SimpleNamespace(get_tool_config=lambda _name: SimpleNamespace(model_extra={"api_key": "synthetic-key"}))
+
+    monkeypatch.setattr(youcom_tools, "get_app_config", load_config or config)
+
+
+async def test_youcom_search_request_runs_on_the_event_loop(monkeypatch) -> None:
+    """The request is awaited on the loop, not dispatched to an executor thread."""
+    request_threads: list[int] = []
+    clients: list[str] = []
+    loop_thread = threading.get_ident()
+    _patch_transport(monkeypatch, request_threads, clients)
+    _patch_config(monkeypatch)
+
+    result = await youcom_tools.web_search_tool.ainvoke({"query": "vector databases"})
+
+    assert '"error": "No results found"' in result
+    assert request_threads, "the request must reach the transport"
+    assert all(thread == loop_thread for thread in request_threads)
+    assert clients == ["AsyncClient"], "the request must go out through the async client"
+
+
+async def test_youcom_config_lookup_does_not_block_loop(monkeypatch) -> None:
+    """The tool body runs on the loop, so the config file read must not."""
+    config_threads: list[int] = []
+    loop_thread = threading.get_ident()
+
+    def load_config():
+        # Keep a real file read in the lookup so the strict blocking-I/O gate
+        # fails if the tool resolves config on the event loop.
+        Path(__file__).read_text(encoding="utf-8")
+        config_threads.append(threading.get_ident())
+        return SimpleNamespace(get_tool_config=lambda _name: SimpleNamespace(model_extra={"api_key": "synthetic-key"}))
+
+    request_threads: list[int] = []
+    clients: list[str] = []
+    _patch_transport(monkeypatch, request_threads, clients)
+    _patch_config(monkeypatch, load_config)
+
+    result = await youcom_tools.web_search_tool.ainvoke({"query": "vector databases"})
+
+    assert '"error": "No results found"' in result
+    assert config_threads, "config lookup must run"
+    assert all(thread != loop_thread for thread in config_threads)
+    assert clients == ["AsyncClient"], "the request must go out through the async client"
+
+
+async def test_youcom_user_agent_reads_metadata_off_the_loop_once(monkeypatch) -> None:
+    """The cold User-Agent read goes to an executor; the warm hit stays in memory.
+
+    ``_user_agent`` is cached, so only the first call reads the installed
+    package metadata. That read must stay off the event loop, and every later
+    call is a pure memory hit that must not pay an executor round-trip.
+    """
+    loop_thread = threading.get_ident()
+    reads: list[int] = []
+    real_version = youcom_tools.version
+
+    def read_version(name: str) -> str:
+        reads.append(threading.get_ident())
+        return real_version(name)
+
+    monkeypatch.setattr(youcom_tools, "version", read_version)
+    youcom_tools._user_agent.cache_clear()
+    try:
+        cold = await youcom_tools._resolve_user_agent()
+        assert reads, "the cold call must read the installed package metadata"
+        assert all(thread != loop_thread for thread in reads), "the metadata read must not run on the event loop"
+
+        dispatched: list[object] = []
+        real_to_thread = asyncio.to_thread
+
+        async def spy_to_thread(func, /, *args, **kwargs):
+            dispatched.append(func)
+            return await real_to_thread(func, *args, **kwargs)
+
+        monkeypatch.setattr(asyncio, "to_thread", spy_to_thread)
+        reads.clear()
+
+        warm = await youcom_tools._resolve_user_agent()
+
+        assert warm == cold
+        assert not reads, "the warm call must not read the metadata again"
+        assert not dispatched, "the warm call must not pay an executor round-trip"
+    finally:
+        youcom_tools._user_agent.cache_clear()
diff --git a/backend/tests/test_image_result_url_safety.py b/backend/tests/test_image_result_url_safety.py
index 83308af8cb..4c7858f99e 100644
--- a/backend/tests/test_image_result_url_safety.py
+++ b/backend/tests/test_image_result_url_safety.py
@@ -80,7 +80,7 @@ def _stub_exa(module, url):
 
 def _stub_youcom(module, url):
     data = {"results": {"web": [{"title": "t", "url": url, "description": "c"}]}}
-    return [patch.object(module, "_get_api_key", return_value="k"), patch.object(module, "_search", return_value=data)], _sync(module.web_search_tool)
+    return [patch.object(module, "_search", new=AsyncMock(return_value=data))], _async(module.web_search_tool)
 
 
 def _stub_tencent_wsa(module, url):
diff --git a/backend/tests/test_youcom_tools.py b/backend/tests/test_youcom_tools.py
index bfddeed9dd..38578e522d 100644
--- a/backend/tests/test_youcom_tools.py
+++ b/backend/tests/test_youcom_tools.py
@@ -2,7 +2,7 @@
 
 import json
 import logging
-from unittest.mock import MagicMock, patch
+from unittest.mock import AsyncMock, MagicMock, patch
 
 import httpx
 import pytest
@@ -10,6 +10,8 @@ import pytest
 KEYED_ENDPOINT = "https://api.you.com/v1/search"
 KEYLESS_ENDPOINT = "https://api.you.com/v1/agents/search"
 
+pytestmark = pytest.mark.anyio
+
 
 @pytest.fixture
 def mock_config_with_key():
@@ -37,15 +39,15 @@ def _make_response(payload: object) -> MagicMock:
 
 
 def _patch_get(mock_resp: MagicMock):
-    """Patch httpx.Client so the context-managed .get returns mock_resp."""
-    patcher = patch("deerflow.community.youcom.tools.httpx.Client")
+    """Patch httpx.AsyncClient so the context-managed .get returns mock_resp."""
+    patcher = patch("deerflow.community.youcom.tools.httpx.AsyncClient")
     mock_client_cls = patcher.start()
-    mock_client_cls.return_value.__enter__.return_value.get.return_value = mock_resp
+    mock_client_cls.return_value.__aenter__.return_value.get = AsyncMock(return_value=mock_resp)
     return patcher, mock_client_cls
 
 
 def _get_call(mock_client_cls):
-    return mock_client_cls.return_value.__enter__.return_value.get.call_args
+    return mock_client_cls.return_value.__aenter__.return_value.get.call_args
 
 
 def _web(**overrides) -> dict:
@@ -54,16 +56,16 @@ def _web(**overrides) -> dict:
     return result
 
 
-class TestGetApiKey:
+class TestResolveToolSettings:
     def test_returns_config_key_when_present(self):
         with patch("deerflow.community.youcom.tools.get_app_config") as mock:
             tool_config = MagicMock()
             tool_config.model_extra = {"api_key": "from-config"}
             mock.return_value.get_tool_config.return_value = tool_config
 
-            from deerflow.community.youcom.tools import _get_api_key
+            from deerflow.community.youcom.tools import _resolve_tool_settings
 
-            assert _get_api_key("web_search") == "from-config"
+            assert _resolve_tool_settings("web_search")[0] == "from-config"
 
     def test_falls_back_to_env_when_config_key_blank(self):
         with patch("deerflow.community.youcom.tools.get_app_config") as mock:
@@ -71,27 +73,27 @@ class TestGetApiKey:
             tool_config.model_extra = {"api_key": "   "}
             mock.return_value.get_tool_config.return_value = tool_config
             with patch.dict("os.environ", {"YDC_API_KEY": "env-key"}, clear=True):
-                from deerflow.community.youcom.tools import _get_api_key
+                from deerflow.community.youcom.tools import _resolve_tool_settings
 
-                assert _get_api_key("web_search") == "env-key"
+                assert _resolve_tool_settings("web_search")[0] == "env-key"
 
     def test_returns_none_when_no_key_anywhere(self):
         """No key is not an error: it selects the keyless endpoint."""
         with patch("deerflow.community.youcom.tools.get_app_config") as mock:
             mock.return_value.get_tool_config.return_value = None
             with patch.dict("os.environ", {}, clear=True):
-                from deerflow.community.youcom.tools import _get_api_key
+                from deerflow.community.youcom.tools import _resolve_tool_settings
 
-                assert _get_api_key("web_search") is None
+                assert _resolve_tool_settings("web_search")[0] is None
 
 
 class TestEndpointSelection:
-    def test_configured_key_uses_keyed_endpoint_with_header(self, mock_config_with_key):
+    async def test_configured_key_uses_keyed_endpoint_with_header(self, mock_config_with_key):
         patcher, mock_client_cls = _patch_get(_make_response({"results": {"web": [_web()]}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            web_search_tool.invoke({"query": "test"})
+            await web_search_tool.ainvoke({"query": "test"})
             call = _get_call(mock_client_cls)
         finally:
             patcher.stop()
@@ -100,14 +102,14 @@ class TestEndpointSelection:
         assert call.kwargs["headers"]["X-API-Key"] == "test-ydc-key"
         assert call.kwargs["params"] == {"query": "test", "count": 5}
 
-    def test_no_key_uses_keyless_endpoint_without_auth_header(self, mock_config_no_key):
+    async def test_no_key_uses_keyless_endpoint_without_auth_header(self, mock_config_no_key):
         """The keyless endpoint rejects an auth header, so none may be sent."""
         with patch.dict("os.environ", {}, clear=True):
             patcher, mock_client_cls = _patch_get(_make_response({"results": {"web": [_web()]}}))
             try:
                 from deerflow.community.youcom.tools import web_search_tool
 
-                web_search_tool.invoke({"query": "test"})
+                await web_search_tool.ainvoke({"query": "test"})
                 call = _get_call(mock_client_cls)
             finally:
                 patcher.stop()
@@ -115,13 +117,13 @@ class TestEndpointSelection:
         assert call.args[0] == KEYLESS_ENDPOINT
         assert "X-API-Key" not in call.kwargs["headers"]
 
-    def test_env_key_uses_keyed_endpoint(self, mock_config_no_key):
+    async def test_env_key_uses_keyed_endpoint(self, mock_config_no_key):
         with patch.dict("os.environ", {"YDC_API_KEY": "env-key"}, clear=True):
             patcher, mock_client_cls = _patch_get(_make_response({"results": {"web": [_web()]}}))
             try:
                 from deerflow.community.youcom.tools import web_search_tool
 
-                web_search_tool.invoke({"query": "test"})
+                await web_search_tool.ainvoke({"query": "test"})
                 call = _get_call(mock_client_cls)
             finally:
                 patcher.stop()
@@ -130,7 +132,7 @@ class TestEndpointSelection:
         assert call.kwargs["headers"]["X-API-Key"] == "env-key"
 
     @pytest.mark.parametrize("with_key", [True, False])
-    def test_identifies_deerflow_in_user_agent(self, with_key, mock_config_no_key):
+    async def test_identifies_deerflow_in_user_agent(self, with_key, mock_config_no_key):
         """Both endpoints identify DeerFlow so You.com can attribute the traffic."""
         env = {"YDC_API_KEY": "k"} if with_key else {}
         with patch.dict("os.environ", env, clear=True):
@@ -138,7 +140,7 @@ class TestEndpointSelection:
             try:
                 from deerflow.community.youcom.tools import web_search_tool
 
-                web_search_tool.invoke({"query": "test"})
+                await web_search_tool.ainvoke({"query": "test"})
                 call = _get_call(mock_client_cls)
             finally:
                 patcher.stop()
@@ -149,7 +151,7 @@ class TestEndpointSelection:
 
 
 class TestWebSearchTool:
-    def test_returns_normalized_list_with_joined_snippets(self, mock_config_with_key):
+    async def test_returns_normalized_list_with_joined_snippets(self, mock_config_with_key):
         payload = {
             "results": {
                 "web": [
@@ -162,7 +164,7 @@ class TestWebSearchTool:
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "vector databases"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "vector databases"}))
         finally:
             patcher.stop()
 
@@ -171,7 +173,7 @@ class TestWebSearchTool:
             {"title": "B", "url": "https://ex.com/b", "snippet": "s3"},
         ]
 
-    def test_falls_back_to_description_when_no_snippets(self, mock_config_with_key):
+    async def test_falls_back_to_description_when_no_snippets(self, mock_config_with_key):
         """News hits carry only a description; web hits with empty snippets do too."""
         payload = {
             "results": {
@@ -183,13 +185,13 @@ class TestWebSearchTool:
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "news"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "news"}))
         finally:
             patcher.stop()
 
         assert [r["snippet"] for r in parsed] == ["web-desc", "news-desc"]
 
-    def test_web_and_news_merged_and_trimmed_to_count(self, mock_config_with_key):
+    async def test_web_and_news_merged_and_trimmed_to_count(self, mock_config_with_key):
         """`count` applies per section, so the merged list can overshoot it."""
         payload = {
             "results": {
@@ -201,31 +203,31 @@ class TestWebSearchTool:
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
         assert len(parsed) == 5
         assert [r["title"] for r in parsed] == ["W0", "W1", "W2", "W3", "W4"]
 
-    def test_agent_max_results_is_honored_over_config(self, mock_config_with_key):
+    async def test_agent_max_results_is_honored_over_config(self, mock_config_with_key):
         patcher, mock_client_cls = _patch_get(_make_response({"results": {"web": [_web()]}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            web_search_tool.invoke({"query": "test", "max_results": 20})
+            await web_search_tool.ainvoke({"query": "test", "max_results": 20})
             params = _get_call(mock_client_cls).kwargs["params"]
         finally:
             patcher.stop()
 
         assert params["count"] == 20
 
-    def test_config_max_results_used_when_caller_omits(self, mock_config_with_key):
+    async def test_config_max_results_used_when_caller_omits(self, mock_config_with_key):
         patcher, mock_client_cls = _patch_get(_make_response({"results": {"web": [_web()]}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            web_search_tool.invoke({"query": "test"})
+            await web_search_tool.ainvoke({"query": "test"})
             params = _get_call(mock_client_cls).kwargs["params"]
         finally:
             patcher.stop()
@@ -233,7 +235,7 @@ class TestWebSearchTool:
         assert params["count"] == 5
 
     @pytest.mark.parametrize(("max_results", "expected"), [(0, 5), (-2, 5), (1, 1), (100, 100), ("500", 100)])
-    def test_max_results_clamped_to_provider_bounds(self, max_results, expected):
+    async def test_max_results_clamped_to_provider_bounds(self, max_results, expected):
         with patch("deerflow.community.youcom.tools.get_app_config") as mock:
             tool_config = MagicMock()
             tool_config.model_extra = {"api_key": "k", "max_results": max_results}
@@ -242,14 +244,14 @@ class TestWebSearchTool:
             try:
                 from deerflow.community.youcom.tools import web_search_tool
 
-                web_search_tool.invoke({"query": "test"})
+                await web_search_tool.ainvoke({"query": "test"})
                 params = _get_call(mock_client_cls).kwargs["params"]
             finally:
                 patcher.stop()
 
         assert params["count"] == expected
 
-    def test_invalid_max_results_falls_back_to_default_with_warning(self, caplog):
+    async def test_invalid_max_results_falls_back_to_default_with_warning(self, caplog):
         with patch("deerflow.community.youcom.tools.get_app_config") as mock:
             tool_config = MagicMock()
             tool_config.model_extra = {"api_key": "k", "max_results": "not-a-number"}
@@ -259,7 +261,7 @@ class TestWebSearchTool:
                 from deerflow.community.youcom.tools import web_search_tool
 
                 with caplog.at_level(logging.WARNING, logger="deerflow.community.youcom.tools"):
-                    web_search_tool.invoke({"query": "test"})
+                    await web_search_tool.ainvoke({"query": "test"})
                 params = _get_call(mock_client_cls).kwargs["params"]
             finally:
                 patcher.stop()
@@ -267,46 +269,46 @@ class TestWebSearchTool:
         assert params["count"] == 5
         assert any("Invalid You.com max_results" in record.message for record in caplog.records)
 
-    def test_empty_results_returns_error_json(self, mock_config_with_key):
+    async def test_empty_results_returns_error_json(self, mock_config_with_key):
         patcher, _ = _patch_get(_make_response({"results": {"web": []}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "no results"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "no results"}))
         finally:
             patcher.stop()
 
         assert parsed["error"] == "No results found"
         assert parsed["query"] == "no results"
 
-    def test_missing_results_section_returns_error_json(self, mock_config_with_key):
+    async def test_missing_results_section_returns_error_json(self, mock_config_with_key):
         patcher, _ = _patch_get(_make_response({"metadata": {"latency": 0.1}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
         assert parsed["error"] == "No results found"
 
-    def test_non_dict_payload_returns_format_error(self, mock_config_with_key):
+    async def test_non_dict_payload_returns_format_error(self, mock_config_with_key):
         patcher, _ = _patch_get(_make_response(["not", "a", "dict"]))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
         assert "unexpected response format" in parsed["error"]
 
-    def test_partial_fields_default_to_empty_string(self, mock_config_with_key):
+    async def test_partial_fields_default_to_empty_string(self, mock_config_with_key):
         patcher, _ = _patch_get(_make_response({"results": {"web": [{}]}}))
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
@@ -321,7 +323,7 @@ class TestWebSearchTool:
             (500, None),
         ],
     )
-    def test_http_error_returns_structured_error(self, status, hint, mock_config_with_key):
+    async def test_http_error_returns_structured_error(self, status, hint, mock_config_with_key):
         mock_resp = MagicMock()
         mock_resp.raise_for_status.side_effect = httpx.HTTPStatusError(
             str(status),
@@ -332,7 +334,7 @@ class TestWebSearchTool:
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
@@ -340,13 +342,13 @@ class TestWebSearchTool:
         if hint:
             assert hint in parsed["error"]
 
-    def test_network_exception_returns_error_json(self, mock_config_with_key):
+    async def test_network_exception_returns_error_json(self, mock_config_with_key):
         patcher, mock_client_cls = _patch_get(MagicMock())
-        mock_client_cls.return_value.__enter__.return_value.get.side_effect = Exception("timeout")
+        mock_client_cls.return_value.__aenter__.return_value.get.side_effect = Exception("timeout")
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            parsed = json.loads(web_search_tool.invoke({"query": "test"}))
+            parsed = json.loads(await web_search_tool.ainvoke({"query": "test"}))
         finally:
             patcher.stop()
 
@@ -358,7 +360,7 @@ class TestWebSearchTool:
     [float("inf"), True, 3.5],
     ids=["yaml-inf", "bool", "non-integral-float"],
 )
-def test_invalid_max_results_shapes_fall_back_to_default(raw):
+async def test_invalid_max_results_shapes_fall_back_to_default(raw):
     """Invalid max_results shapes fall back to the default, never crash or truncate.
 
     These pin the shared-owner bar for this provider: a YAML ``.inf`` makes
@@ -375,7 +377,7 @@ def test_invalid_max_results_shapes_fall_back_to_default(raw):
         try:
             from deerflow.community.youcom.tools import web_search_tool
 
-            web_search_tool.invoke({"query": "test"})
+            await web_search_tool.ainvoke({"query": "test"})
             params = _get_call(mock_client_cls).kwargs["params"]
         finally:
             patcher.stop()