diff --git a/tests/test_ccproxy_manager.py b/tests/test_ccproxy_manager.py
index 652abd5..7b0c7f9 100644
--- a/tests/test_ccproxy_manager.py
+++ b/tests/test_ccproxy_manager.py
@@ -58,7 +58,7 @@ class TestCheckCcproxyAuth:
         mock_run.return_value = MagicMock(
             returncode=0, stdout="Authenticated", stderr=""
         )
-        valid, msg = check_ccproxy_auth("codex")
+        valid, _msg = check_ccproxy_auth("codex")
         assert valid is True
         cmd = mock_run.call_args[0][0]
         assert cmd[1:] == ["auth", "status", "codex"]
diff --git a/tests/test_channel_comprehensive.py b/tests/test_channel_comprehensive.py
index 705628b..8d1d241 100644
--- a/tests/test_channel_comprehensive.py
+++ b/tests/test_channel_comprehensive.py
@@ -249,7 +249,7 @@ class TestRetryAsync:
         )
         # With 50% jitter, not all delays should be identical
         if len(delays) > 1:
-            assert len(set(f"{d:.4f}" for d in delays)) > 1
+            assert len({f"{d:.4f}" for d in delays}) > 1
 
 
 # ═══════════════════════════════════════════════════════════════════
@@ -1438,10 +1438,10 @@ class TestInboundConsumer:
         async def _test():
             consumer = self._make_consumer()
             # Start and immediately stop
-            asyncio.create_task(consumer.run())
+            task = asyncio.create_task(consumer.run())
             await asyncio.sleep(0.1)
             await consumer.stop()
-            await asyncio.sleep(0.1)
+            await task
             assert consumer._stopping is True
 
         _run(_test())
diff --git a/tests/test_compact_command.py b/tests/test_compact_command.py
index 9035ff5..c78d211 100644
--- a/tests/test_compact_command.py
+++ b/tests/test_compact_command.py
@@ -1,38 +1,29 @@
 """Tests for the /compact command (compact_conversation helper)."""
 
-import asyncio
 from types import SimpleNamespace
 from unittest.mock import AsyncMock, MagicMock, patch
 
-import pytest
-
-
-@pytest.fixture
-def _run():
-    """Helper to run async tests."""
-    loop = asyncio.new_event_loop()
-    yield loop.run_until_complete
-    loop.close()
+from tests.conftest import run_async as _run
 
 
 class TestCompactGuards:
     """Guard conditions that return early without touching the middleware."""
 
-    def test_no_agent(self, _run):
+    def test_no_agent(self):
         from EvoScientist.cli.commands import compact_conversation
 
         result = _run(compact_conversation(agent=None, thread_id="abc"))
         assert result.status == "noop"
         assert "Nothing to compact" in result.message
 
-    def test_no_thread_id(self, _run):
+    def test_no_thread_id(self):
         from EvoScientist.cli.commands import compact_conversation
 
         result = _run(compact_conversation(agent=MagicMock(), thread_id=None))
         assert result.status == "noop"
         assert "Nothing to compact" in result.message
 
-    def test_empty_messages(self, _run):
+    def test_empty_messages(self):
         from EvoScientist.cli.commands import compact_conversation
 
         agent = MagicMock()
@@ -43,7 +34,7 @@ class TestCompactGuards:
         assert result.status == "noop"
         assert "no messages" in result.message
 
-    def test_state_read_failure(self, _run):
+    def test_state_read_failure(self):
         from EvoScientist.cli.commands import compact_conversation
 
         agent = MagicMock()
@@ -57,7 +48,7 @@ class TestCompactGuards:
 class TestCompactCutoffZero:
     """When cutoff == 0, conversation is within retention budget."""
 
-    def test_nothing_to_compact_short_conversation(self, _run):
+    def test_nothing_to_compact_short_conversation(self):
         from EvoScientist.cli.commands import compact_conversation
 
         agent = MagicMock()
@@ -102,7 +93,7 @@ class TestCompactCutoffZero:
 class TestCompactNegligibleSavings:
     """When cutoff > 0 but savings are too small to be worth it."""
 
-    def test_skip_when_few_messages_and_low_tokens(self, _run):
+    def test_skip_when_few_messages_and_low_tokens(self):
         from EvoScientist.cli.commands import compact_conversation
 
         agent = MagicMock()
@@ -151,7 +142,7 @@ class TestCompactNegligibleSavings:
         # No LLM call should have been made
         mock_middleware_inst._acreate_summary.assert_not_called()
 
-    def test_still_compacts_when_few_messages_but_high_tokens(self, _run):
+    def test_still_compacts_when_few_messages_but_high_tokens(self):
         """2 messages but they account for >2% of tokens — should compact."""
         from langchain_core.messages import HumanMessage
 
@@ -211,7 +202,7 @@ class TestCompactNegligibleSavings:
 class TestCompactSuccess:
     """Normal compaction flow."""
 
-    def test_successful_compaction(self, _run):
+    def test_successful_compaction(self):
         from langchain_core.messages import HumanMessage
 
         from EvoScientist.cli.commands import compact_conversation
@@ -281,7 +272,7 @@ class TestCompactSuccess:
         assert "_summarization_event" in event_data
         assert event_data["_summarization_event"]["cutoff_index"] == 15
 
-    def test_offload_failure_non_fatal(self, _run):
+    def test_offload_failure_non_fatal(self):
         """Offload failure should not prevent compaction."""
         from langchain_core.messages import HumanMessage
 
diff --git a/tests/test_dingtalk_channel.py b/tests/test_dingtalk_channel.py
index 0d76051..f2fd924 100644
--- a/tests/test_dingtalk_channel.py
+++ b/tests/test_dingtalk_channel.py
@@ -283,11 +283,11 @@ class TestDingTalkProbe:
     def test_missing_client_id(self):
         from EvoScientist.channels.dingtalk.probe import validate_dingtalk
 
-        ok, msg = _run(validate_dingtalk("", "secret"))
+        ok, _msg = _run(validate_dingtalk("", "secret"))
         assert ok is False
 
     def test_missing_client_secret(self):
         from EvoScientist.channels.dingtalk.probe import validate_dingtalk
 
-        ok, msg = _run(validate_dingtalk("id", ""))
+        ok, _msg = _run(validate_dingtalk("id", ""))
         assert ok is False
diff --git a/tests/test_llm.py b/tests/test_llm.py
index 1148726..2546c84 100644
--- a/tests/test_llm.py
+++ b/tests/test_llm.py
@@ -580,7 +580,7 @@ class TestMiniMaxProvider:
     def test_minimax_model_ids_correct(self):
         """MiniMax model IDs should match the official API model names."""
         minimax_models = get_models_for_provider("minimax")
-        model_dict = {name: mid for name, mid in minimax_models}
+        model_dict = dict(minimax_models)
         assert model_dict["minimax-m2.7"] == "MiniMax-M2.7"
         assert model_dict["minimax-m2.5"] == "MiniMax-M2.5"
         assert model_dict["minimax-m2.5-highspeed"] == "MiniMax-M2.5-highspeed"
diff --git a/tests/test_mcp_client.py b/tests/test_mcp_client.py
index a5447ce..d781e68 100644
--- a/tests/test_mcp_client.py
+++ b/tests/test_mcp_client.py
@@ -556,7 +556,8 @@ class TestAddMcpServer:
         add_mcp_server("a", "stdio", command="cmd1")
         add_mcp_server("b", "http", url="http://x")
         data = yaml.safe_load(user_mcp_dir.read_text())
-        assert "a" in data and "b" in data
+        assert "a" in data
+        assert "b" in data
 
 
 class TestRemoveMcpServer:
diff --git a/tests/test_sessions.py b/tests/test_sessions.py
index 6d17740..26449ad 100644
--- a/tests/test_sessions.py
+++ b/tests/test_sessions.py
@@ -25,7 +25,7 @@ from tests.conftest import run_async as _run
 class TestGenerateThreadId(unittest.TestCase):
     def test_length(self):
         tid = generate_thread_id()
-        self.assertEqual(len(tid), 8)
+        assert len(tid) == 8
 
     def test_hex(self):
         tid = generate_thread_id()
@@ -33,58 +33,58 @@ class TestGenerateThreadId(unittest.TestCase):
 
     def test_uniqueness(self):
         ids = {generate_thread_id() for _ in range(100)}
-        self.assertEqual(len(ids), 100)
+        assert len(ids) == 100
 
 
 class TestGetDbPath(unittest.TestCase):
     def test_uses_config_dir(self):
         path = get_db_path()
-        self.assertTrue(str(path).endswith("sessions.db"))
-        self.assertIn(".config", str(path))
-        self.assertIn("evoscientist", str(path))
+        assert str(path).endswith("sessions.db")
+        assert ".config" in str(path)
+        assert "evoscientist" in str(path)
 
 
 class TestFormatRelativeTime(unittest.TestCase):
     def test_none(self):
-        self.assertEqual(_format_relative_time(None), "")
+        assert _format_relative_time(None) == ""
 
     def test_invalid(self):
-        self.assertEqual(_format_relative_time("not-a-date"), "")
+        assert _format_relative_time("not-a-date") == ""
 
     def test_recent(self):
         from datetime import datetime
 
         now = datetime.now(UTC).isoformat()
         result = _format_relative_time(now)
-        self.assertIn("just now", result)
+        assert "just now" in result
 
     def test_minutes(self):
         from datetime import datetime, timedelta
 
         ts = (datetime.now(UTC) - timedelta(minutes=5)).isoformat()
         result = _format_relative_time(ts)
-        self.assertIn("min ago", result)
+        assert "min ago" in result
 
     def test_hours(self):
         from datetime import datetime, timedelta
 
         ts = (datetime.now(UTC) - timedelta(hours=2)).isoformat()
         result = _format_relative_time(ts)
-        self.assertIn("hour", result)
+        assert "hour" in result
 
     def test_days(self):
         from datetime import datetime, timedelta
 
         ts = (datetime.now(UTC) - timedelta(days=3)).isoformat()
         result = _format_relative_time(ts)
-        self.assertIn("day", result)
+        assert "day" in result
 
     def test_months(self):
         from datetime import datetime, timedelta
 
         ts = (datetime.now(UTC) - timedelta(days=65)).isoformat()
         result = _format_relative_time(ts)
-        self.assertIn("month", result)
+        assert "month" in result
 
 
 class TestThreadFunctions(unittest.TestCase):
@@ -183,44 +183,44 @@ class TestThreadFunctions(unittest.TestCase):
     def test_list_threads(self):
         threads = _run(list_threads(limit=10))
         # Should only contain EvoScientist threads
-        self.assertEqual(len(threads), 3)
+        assert len(threads) == 3
         # Most recent first
-        self.assertEqual(threads[0]["thread_id"], "def00001")
+        assert threads[0]["thread_id"] == "def00001"
 
     def test_list_threads_with_message_count(self):
         threads = _run(list_threads(limit=10, include_message_count=True))
-        self.assertIn("message_count", threads[0])
+        assert "message_count" in threads[0]
 
     def test_thread_exists_true(self):
-        self.assertTrue(_run(thread_exists("abc12345")))
+        assert _run(thread_exists("abc12345"))
 
     def test_thread_exists_false(self):
-        self.assertFalse(_run(thread_exists("nonexist")))
+        assert not _run(thread_exists("nonexist"))
 
     def test_find_similar(self):
         similar = _run(find_similar_threads("abc1"))
-        self.assertEqual(len(similar), 2)
-        self.assertIn("abc12345", similar)
-        self.assertIn("abc12399", similar)
+        assert len(similar) == 2
+        assert "abc12345" in similar
+        assert "abc12399" in similar
 
     def test_find_similar_no_match(self):
         similar = _run(find_similar_threads("xyz"))
-        self.assertEqual(len(similar), 0)
+        assert len(similar) == 0
 
     def test_get_most_recent(self):
         recent = _run(get_most_recent())
-        self.assertIsNotNone(recent)
-        self.assertEqual(recent, "def00001")
+        assert recent is not None
+        assert recent == "def00001"
 
     def test_get_thread_metadata(self):
         meta = _run(get_thread_metadata("abc12345"))
-        self.assertIsNotNone(meta)
-        self.assertEqual(meta["workspace_dir"], "/tmp/ws_abc12345")
-        self.assertEqual(meta["model"], "claude-sonnet-4-5")
+        assert meta is not None
+        assert meta["workspace_dir"] == "/tmp/ws_abc12345"
+        assert meta["model"] == "claude-sonnet-4-5"
 
     def test_get_thread_metadata_missing(self):
         meta = _run(get_thread_metadata("nonexist"))
-        self.assertIsNone(meta)
+        assert meta is None
 
     def test_delete_thread(self):
         # Insert a thread to delete
@@ -242,29 +242,29 @@ class TestThreadFunctions(unittest.TestCase):
 
         _run(_insert())
 
-        self.assertTrue(_run(thread_exists("todelete")))
-        self.assertTrue(_run(delete_thread("todelete")))
-        self.assertFalse(_run(thread_exists("todelete")))
+        assert _run(thread_exists("todelete"))
+        assert _run(delete_thread("todelete"))
+        assert not _run(thread_exists("todelete"))
 
     def test_delete_nonexistent(self):
-        self.assertFalse(_run(delete_thread("nope1234")))
+        assert not _run(delete_thread("nope1234"))
 
     # -- Agent isolation: OtherAgent data should never be visible --
 
     def test_thread_exists_ignores_other_agent(self):
-        self.assertFalse(_run(thread_exists("zzz99999")))
+        assert not _run(thread_exists("zzz99999"))
 
     def test_find_similar_ignores_other_agent(self):
         similar = _run(find_similar_threads("zzz"))
-        self.assertEqual(len(similar), 0)
+        assert len(similar) == 0
 
     def test_get_metadata_ignores_other_agent(self):
         meta = _run(get_thread_metadata("zzz99999"))
-        self.assertIsNone(meta)
+        assert meta is None
 
     def test_delete_ignores_other_agent(self):
         # Should not delete OtherAgent's data
-        self.assertFalse(_run(delete_thread("zzz99999")))
+        assert not _run(delete_thread("zzz99999"))
 
     def test_delete_thread_preserves_other_agent_writes(self):
         """Deleting a shared thread_id must only remove writes linked to
@@ -329,8 +329,8 @@ class TestThreadFunctions(unittest.TestCase):
                 return [r[0] for r in rows]
 
         remaining = _run(_check())
-        self.assertIn("cp_other_shared", remaining)
-        self.assertNotIn("cp_evo_shared", remaining)
+        assert "cp_other_shared" in remaining
+        assert "cp_evo_shared" not in remaining
 
 
 if __name__ == "__main__":
diff --git a/tests/test_summarization.py b/tests/test_summarization.py
index 4af6844..4fbfa4f 100644
--- a/tests/test_summarization.py
+++ b/tests/test_summarization.py
@@ -203,10 +203,11 @@ class TestExtractSummarizationText:
 
     def test_content_blocks(self):
         class Msg:
-            content = [
-                {"type": "text", "text": "part1"},
-                {"type": "text", "text": "part2"},
-            ]
+            def __init__(self):
+                self.content = [
+                    {"type": "text", "text": "part1"},
+                    {"type": "text", "text": "part2"},
+                ]
 
         assert _extract_summarization_text(Msg()) == "part1part2"
 
@@ -214,13 +215,15 @@ class TestExtractSummarizationText:
         """Content blocks may include 'index' field — should still extract text."""
 
         class Msg:
-            content = [{"type": "text", "text": " vs", "index": 1}]
+            def __init__(self):
+                self.content = [{"type": "text", "text": " vs", "index": 1}]
 
         assert _extract_summarization_text(Msg()) == " vs"
 
     def test_empty_list(self):
         class Msg:
-            content = []
+            def __init__(self):
+                self.content = []
 
         assert _extract_summarization_text(Msg()) == ""
 
@@ -232,15 +235,17 @@ class TestExtractSummarizationText:
 
     def test_mixed_block_types(self):
         class Msg:
-            content = [
-                {"type": "text", "text": "hello"},
-                {"type": "image", "url": "..."},
-            ]
+            def __init__(self):
+                self.content = [
+                    {"type": "text", "text": "hello"},
+                    {"type": "image", "url": "..."},
+                ]
 
         assert _extract_summarization_text(Msg()) == "hello"
 
     def test_string_blocks_in_list(self):
         class Msg:
-            content = ["hello", "world"]
+            def __init__(self):
+                self.content = ["hello", "world"]
 
         assert _extract_summarization_text(Msg()) == "helloworld"
diff --git a/tests/test_wechat_channel.py b/tests/test_wechat_channel.py
index 2822328..ce8d7eb 100644
--- a/tests/test_wechat_channel.py
+++ b/tests/test_wechat_channel.py
@@ -306,7 +306,7 @@ class TestWeChatCrypto:
         # Parse and verify the encrypted content decrypts back
         root = ET.fromstring(xml_reply)
         encrypt = root.find("Encrypt").text
-        decrypted, app_id = crypto.decrypt(encrypt)
+        decrypted, _app_id = crypto.decrypt(encrypt)
         assert decrypted == msg