fix(memory): validate save_memory payload before persisting

tests/test_memory_consolidation_types.py

@@ -97,7 +97,6 @@ class TestMemoryConsolidationTypeHandling:
         store = MemoryStore(tmp_path)
         provider = AsyncMock()
 
-        # Simulate arguments being a JSON string (not yet parsed)
         response = LLMResponse(
             content=None,
             tool_calls=[
@@ -152,7 +151,6 @@ class TestMemoryConsolidationTypeHandling:
         store = MemoryStore(tmp_path)
         provider = AsyncMock()
 
-        # Simulate arguments being a list containing a dict
         response = LLMResponse(
             content=None,
             tool_calls=[
@@ -220,3 +218,95 @@ class TestMemoryConsolidationTypeHandling:
         result = await store.consolidate(session, provider, "test-model", memory_window=50)
 
         assert result is False
+
+    @pytest.mark.asyncio
+    async def test_missing_history_entry_returns_false_without_writing(self, tmp_path: Path) -> None:
+        """Do not persist partial results when required fields are missing."""
+        store = MemoryStore(tmp_path)
+        provider = AsyncMock()
+        provider.chat = AsyncMock(
+            return_value=LLMResponse(
+                content=None,
+                tool_calls=[
+                    ToolCallRequest(
+                        id="call_1",
+                        name="save_memory",
+                        arguments={"memory_update": "# Memory\nOnly memory update"},
+                    )
+                ],
+            )
+        )
+        session = _make_session(message_count=60)
+
+        result = await store.consolidate(session, provider, "test-model", memory_window=50)
+
+        assert result is False
+        assert not store.history_file.exists()
+        assert not store.memory_file.exists()
+        assert session.last_consolidated == 0
+
+    @pytest.mark.asyncio
+    async def test_missing_memory_update_returns_false_without_writing(self, tmp_path: Path) -> None:
+        """Do not append history if memory_update is missing."""
+        store = MemoryStore(tmp_path)
+        provider = AsyncMock()
+        provider.chat = AsyncMock(
+            return_value=LLMResponse(
+                content=None,
+                tool_calls=[
+                    ToolCallRequest(
+                        id="call_1",
+                        name="save_memory",
+                        arguments={"history_entry": "[2026-01-01] Partial output."},
+                    )
+                ],
+            )
+        )
+        session = _make_session(message_count=60)
+
+        result = await store.consolidate(session, provider, "test-model", memory_window=50)
+
+        assert result is False
+        assert not store.history_file.exists()
+        assert not store.memory_file.exists()
+        assert session.last_consolidated == 0
+
+    @pytest.mark.asyncio
+    async def test_null_required_field_returns_false_without_writing(self, tmp_path: Path) -> None:
+        """Null required fields should be rejected before persistence."""
+        store = MemoryStore(tmp_path)
+        provider = AsyncMock()
+        provider.chat = AsyncMock(
+            return_value=_make_tool_response(
+                history_entry=None,
+                memory_update="# Memory\nUser likes testing.",
+            )
+        )
+        session = _make_session(message_count=60)
+
+        result = await store.consolidate(session, provider, "test-model", memory_window=50)
+
+        assert result is False
+        assert not store.history_file.exists()
+        assert not store.memory_file.exists()
+        assert session.last_consolidated == 0
+
+    @pytest.mark.asyncio
+    async def test_empty_history_entry_returns_false_without_writing(self, tmp_path: Path) -> None:
+        """Empty history entries should be rejected to avoid blank archival records."""
+        store = MemoryStore(tmp_path)
+        provider = AsyncMock()
+        provider.chat = AsyncMock(
+            return_value=_make_tool_response(
+                history_entry="   ",
+                memory_update="# Memory\nUser likes testing.",
+            )
+        )
+        session = _make_session(message_count=60)
+
+        result = await store.consolidate(session, provider, "test-model", memory_window=50)
+
+        assert result is False
+        assert not store.history_file.exists()
+        assert not store.memory_file.exists()
+        assert session.last_consolidated == 0