diff --git a/src/basic_memory/mcp/project_context.py b/src/basic_memory/mcp/project_context.py
index 02f56134..a81b3fac 100644
--- a/src/basic_memory/mcp/project_context.py
+++ b/src/basic_memory/mcp/project_context.py
@@ -40,6 +40,29 @@ def set_workspace_provider(provider: Callable[[], Awaitable[list[WorkspaceInfo]]
     _workspace_provider = provider
 
 
+async def _resolve_default_project_from_api() -> Optional[str]:
+    """Query the projects API for the default project.
+
+    Used as a fallback when ConfigManager has no local config (cloud mode).
+    """
+    from basic_memory.mcp.async_client import get_client
+
+    try:
+        async with get_client() as client:
+            response = await client.get("/v2/projects/")
+            if response.status_code == 200:
+                project_list = ProjectList.model_validate(response.json())
+                if project_list.default_project:
+                    return project_list.default_project
+                # Fallback: find project with is_default=True
+                for p in project_list.projects:
+                    if p.is_default:
+                        return p.name
+    except Exception:
+        pass
+    return None
+
+
 async def resolve_project_parameter(
     project: Optional[str] = None,
     allow_discovery: bool = False,
@@ -66,11 +89,16 @@ async def resolve_project_parameter(
     Returns:
         Resolved project name or None if no resolution possible
     """
-    # Load config for any values not explicitly provided
+    # Load config for any values not explicitly provided.
+    # ConfigManager reads from the local config file, which doesn't exist in cloud mode.
+    # When it returns None, fall back to querying the projects API for the is_default flag.
     if default_project is None:
         config = ConfigManager().config
         default_project = config.default_project
 
+    if default_project is None:
+        default_project = await _resolve_default_project_from_api()
+
     # Create resolver with configuration and resolve
     resolver = ProjectResolver.from_env(
         default_project=default_project,
diff --git a/tests/mcp/test_tool_recent_activity.py b/tests/mcp/test_tool_recent_activity.py
index f9194071..8ef7b786 100644
--- a/tests/mcp/test_tool_recent_activity.py
+++ b/tests/mcp/test_tool_recent_activity.py
@@ -128,69 +128,16 @@ async def test_recent_activity_type_invalid(client, test_project, test_graph):
 
 
 @pytest.mark.asyncio
-async def test_recent_activity_discovery_mode(client, test_project, test_graph, config_manager):
-    """Test that recent_activity discovery mode works without project parameter."""
-    # Clear default_project to test discovery mode
-    cfg = config_manager.load_config()
-    cfg.default_project = None
-    config_manager.save_config(cfg)
-
-    # Test discovery mode (no project parameter)
+async def test_recent_activity_uses_default_project(client, test_project, test_graph):
+    """When no project parameter is given, recent_activity uses the default project."""
+    # Call without explicit project — should resolve to the default
     result = await recent_activity()
     assert result is not None
     assert isinstance(result, str)
 
-    # Check that we get a formatted summary
-    assert "Recent Activity Summary" in result
-    assert "Most Active Project:" in result or "Other Active Projects:" in result
-    assert "Summary:" in result
-    assert "active projects" in result
-
-    # Should contain project discovery guidance
-    assert "Suggested project:" in result or "Multiple active projects" in result
-    assert "Session reminder:" in result
-
-
-@pytest.mark.asyncio
-async def test_recent_activity_discovery_mode_no_activity(client, test_project, config_manager):
-    """If there is no activity in any project, discovery mode should say so."""
-    # Clear default_project to test discovery mode
-    cfg = config_manager.load_config()
-    cfg.default_project = None
-    config_manager.save_config(cfg)
-
-    result = await recent_activity()
-    assert "Recent Activity Summary" in result
-    assert "No recent activity found in any project." in result
-
-
-@pytest.mark.asyncio
-async def test_recent_activity_discovery_mode_multiple_active_projects(
-    app, client, test_project, tmp_path_factory, config_manager
-):
-    """Discovery mode should use the multi-project guidance when multiple projects have activity."""
-    # Clear default_project to test discovery mode
-    cfg = config_manager.load_config()
-    cfg.default_project = None
-    config_manager.save_config(cfg)
-
-    from basic_memory.mcp.tools import create_memory_project, write_note
-
-    second_root = tmp_path_factory.mktemp("second-project-home")
-
-    result = await create_memory_project(
-        project_name="second-project",
-        project_path=str(second_root),
-        set_default=False,
-    )
-    assert result.startswith("✓")
-
-    await write_note(project=test_project.name, title="One", directory="notes", content="one")
-    await write_note(project="second-project", title="Two", directory="notes", content="two")
-
-    out = await recent_activity()
-    assert "Recent Activity Summary" in out
-    assert "or would you prefer a different project" in out
+    # Should return project-specific output for the default project
+    assert "Recent Activity:" in result
+    assert "Activity Summary:" in result
 
 
 def test_recent_activity_format_relative_time_and_truncate_helpers():