fix(code): wrap MCP viewer navigation

libs/code/deepagents_code/app.py

@@ -12990,7 +12990,7 @@ async def action_toggle_auto_approve(self) -> None:
             self.screen.action_move_up()
             return
         if isinstance(self.screen, MCPViewerScreen):
-            self.screen.action_move_up()
+            self.screen.action_jump_up()
             return
         # shift+tab is reused for navigation inside modal screens (e.g.
         # ModelSelectorScreen); skip the toggle so it doesn't fire through.

libs/code/deepagents_code/tui/widgets/mcp_viewer.py

@@ -1345,10 +1345,10 @@ def _move_to(self, index: int) -> None:
             # bottom for up).
 
     def _move_selection(self, delta: int) -> None:
-        """Move selection by delta row positions, clamped at the list ends.
+        """Move selection by delta row positions within the list bounds.
 
-        No wrap-around — pressing `Down` past the last row stays put rather
-        than jumping to the first. Walks every row (headers + tools).
+        Walks every row (headers + tools). Navigation actions handle wrapping
+        before calling this helper at a list boundary.
 
         Args:
             delta: Number of row positions to move.
@@ -1359,22 +1359,22 @@ def _move_selection(self, delta: int) -> None:
         if 0 <= target < len(self._row_widgets):
             self._move_to(target)
 
-    def _next_tool_row(self, start: int, step: int) -> int | None:
-        """Return the index of the next `MCPToolItem` row in `step` direction.
-
-        Used by `Tab` / `Shift+Tab` to skip server-header rows during
-        cross-tool navigation. Returns `None` when there is no tool row in
-        the requested direction.
+    def _next_server_header(self, start: int, step: int) -> int | None:
+        """Return the next server-header index in the requested direction.
 
         Args:
             start: Index to start searching from (exclusive).
             step: `+1` (forward) or `-1` (backward).
+
+        Returns:
+            The index of the nearest `MCPServerHeaderItem` in that direction,
+            or `None` when no server header exists there.
         """
-        idx = start + step
-        while 0 <= idx < len(self._row_widgets):
-            if isinstance(self._row_widgets[idx], MCPToolItem):
-                return idx
-            idx += step
+        index = start + step
+        while 0 <= index < len(self._row_widgets):
+            if isinstance(self._row_widgets[index], MCPServerHeaderItem):
+                return index
+            index += step
         return None
 
     def _scroll_widget_bottom_to_view(
@@ -1426,19 +1426,22 @@ def action_move_up(self) -> None:
         """Smart up: scroll one row inside a tall expanded row, else jump.
 
         If the selected row's top edge is already inside the viewport, jump
-        to the previous row (header or tool). For rows taller than the
-        viewport, pin the new selection's **bottom** to the viewport so the
-        next `Up` resumes line-stepping through that row; otherwise just
-        ensure the row is visible. `Tab` / `Shift+Tab` skip the smart check
-        AND skip header rows (see `action_jump_up`).
+        to the previous row (header or tool), wrapping to the final row from
+        the first. For rows taller than the viewport, pin the new selection's
+        **bottom** to the viewport so the next `Up` resumes line-stepping
+        through that row; otherwise just ensure the row is visible. `Tab` /
+        `Shift+Tab` jump between server headers (see `action_jump_up`).
         """
         if not self._row_widgets:
             return
         scroll = self.query_one(".mcp-list", VerticalScroll)
         selected = self._row_widgets[self._selected_index]
         if selected.region.y >= scroll.region.y:
             old = self._selected_index
-            self._move_selection(-1)
+            if old == 0:
+                self._move_to(len(self._row_widgets) - 1)
+            else:
+                self._move_selection(-1)
             if self._selected_index != old:
                 self._reveal_selection(
                     self._row_widgets[self._selected_index], direction=-1
@@ -1450,10 +1453,11 @@ def action_move_down(self) -> None:
         """Smart down: scroll one row inside a tall expanded row, else jump.
 
         If the selected row's bottom edge is already inside the viewport,
-        jump to the next row (header or tool). For rows taller than the
-        viewport, pin the new selection's top to the viewport; otherwise
-        just ensure the row is visible. `Tab` / `Shift+Tab` skip the smart
-        check AND skip header rows (see `action_jump_down`).
+        jump to the next row (header or tool), wrapping to the first row from
+        the final one. For rows taller than the viewport, pin the new
+        selection's top to the viewport; otherwise just ensure the row is
+        visible. `Tab` / `Shift+Tab` jump between server headers (see
+        `action_jump_down`).
         """
         if not self._row_widgets:
             return
@@ -1463,7 +1467,10 @@ def action_move_down(self) -> None:
         viewport_bottom = scroll.region.y + scroll.region.height
         if selected_bottom <= viewport_bottom:
             old = self._selected_index
-            self._move_selection(1)
+            if old == len(self._row_widgets) - 1:
+                self._move_to(0)
+            else:
+                self._move_selection(1)
             if self._selected_index != old:
                 self._reveal_selection(
                     self._row_widgets[self._selected_index], direction=1
@@ -1472,17 +1479,26 @@ def action_move_down(self) -> None:
             scroll.scroll_relative(y=1, animate=False)
 
     def action_jump_up(self) -> None:
-        """Jump to the previous tool (Shift+Tab); skips headers."""
-        target = self._next_tool_row(self._selected_index, -1)
+        """Jump backward to the nearest server header (Shift+Tab), wrapping.
+
+        From a tool row this lands on the current server's own header; from a
+        header it moves to the previous server. Wraps to the final header from
+        the top.
+        """
+        target = self._next_server_header(self._selected_index, -1)
         if target is None:
+            target = self._next_server_header(len(self._row_widgets), -1)
+        if target is None or target == self._selected_index:
             return
         self._move_to(target)
         self._reveal_selection(self._row_widgets[target], direction=-1)
 
     def action_jump_down(self) -> None:
-        """Jump to the next tool (Tab); skips headers."""
-        target = self._next_tool_row(self._selected_index, +1)
+        """Jump to the next server (Tab), wrapping at the end."""
+        target = self._next_server_header(self._selected_index, +1)
         if target is None:
+            target = self._next_server_header(-1, +1)
+        if target is None or target == self._selected_index:
             return
         self._move_to(target)
         self._reveal_selection(self._row_widgets[target], direction=1)

libs/code/tests/unit_tests/test_app.py

@@ -17444,6 +17444,36 @@ async def test_notification_detail_shift_tab_moves_cursor_up(self) -> None:
             assert screen._selected != start
             assert app._auto_approve is False
 
+    async def test_mcp_viewer_shift_tab_jumps_to_previous_server(self) -> None:
+        """App-level shift+tab routes to MCPViewerScreen.jump_up."""
+        from deepagents_code.mcp_tools import MCPServerInfo, MCPToolInfo
+        from deepagents_code.tui.widgets.mcp_viewer import MCPViewerScreen
+
+        servers = [
+            MCPServerInfo(
+                name="first",
+                transport="stdio",
+                tools=(MCPToolInfo(name="first-tool", description=""),),
+            ),
+            MCPServerInfo(
+                name="second",
+                transport="stdio",
+                tools=(MCPToolInfo(name="second-tool", description=""),),
+            ),
+        ]
+        app = DeepAgentsApp(agent=MagicMock(), thread_id="t")
+
+        async with app.run_test() as pilot:
+            await pilot.pause()
+            screen = MCPViewerScreen(server_info=servers)
+            app.push_screen(screen)
+            await pilot.pause()
+            assert screen._selected_index == 0
+            await pilot.press("shift+tab")
+            await pilot.pause()
+            assert screen._selected_index == 2
+            assert app._auto_approve is False
+
     async def test_toast_identity_warn_once_semantics(
         self, caplog: pytest.LogCaptureFixture
     ) -> None: