diff --git a/crates/kebab-tui/src/app.rs b/crates/kebab-tui/src/app.rs
index 51e4d36..c0bfd2a 100644
--- a/crates/kebab-tui/src/app.rs
+++ b/crates/kebab-tui/src/app.rs
@@ -58,6 +58,15 @@ impl Mode {
     /// Library / Inspect are read-only navigation panes (`Normal`);
     /// Search / Ask are typing panes so we pre-flip to `Insert` so
     /// the user doesn't have to press `i` after every Tab.
+    ///
+    /// **Auto-flip overrides any prior user-flipped mode on pane
+    /// switch** — if a user pressed `Esc` on Search to read scroll-
+    /// back, then Tab'd back into Ask, the next focus auto-flips
+    /// to Insert (clobbering the user's Normal). This is
+    /// intentional: the typing case is the dominant one for
+    /// Search/Ask, and a sticky-per-pane mode adds state most
+    /// users don't ask for. Sticky mode is a future task —
+    /// current heuristic optimizes for the common case.
     pub fn auto_for(pane: Pane) -> Self {
         match pane {
             Pane::Search | Pane::Ask => Mode::Insert,
diff --git a/crates/kebab-tui/src/lib.rs b/crates/kebab-tui/src/lib.rs
index 669a851..84776b2 100644
--- a/crates/kebab-tui/src/lib.rs
+++ b/crates/kebab-tui/src/lib.rs
@@ -50,3 +50,7 @@ pub use search::{build_jump_command, handle_key_search, render_search};
 // the test) and can pin the in-flight-skip invariant of debounce.
 pub use search::poll_worker as poll_search_worker;
 pub use search::debounce_due as search_debounce_due;
+// p9-fb-12: expose the global mode-toggle intercept so integration
+// tests can pin the i/Esc behavior without standing up the full
+// run loop.
+pub use run::mode_intercept;
diff --git a/crates/kebab-tui/src/run.rs b/crates/kebab-tui/src/run.rs
index 4771734..4250d3e 100644
--- a/crates/kebab-tui/src/run.rs
+++ b/crates/kebab-tui/src/run.rs
@@ -350,7 +350,11 @@ fn render_footer(f: &mut Frame, area: Rect, app: &App) {
 ///   swallow what should be a typed character. We let `i` fall
 ///   through there.)
 /// - Everything else → not consumed.
-fn mode_intercept(app: &mut crate::app::App, key: crossterm::event::KeyEvent) -> bool {
+///
+/// `pub` so integration tests + future TUI consumers can drive the
+/// intercept paths by constructing KeyEvents directly without
+/// standing up the full run loop.
+pub fn mode_intercept(app: &mut crate::app::App, key: crossterm::event::KeyEvent) -> bool {
     use crossterm::event::{KeyCode, KeyModifiers};
     use crate::app::{Mode, Pane};
 
diff --git a/crates/kebab-tui/tests/mode.rs b/crates/kebab-tui/tests/mode.rs
new file mode 100644
index 0000000..c4a8111
--- /dev/null
+++ b/crates/kebab-tui/tests/mode.rs
@@ -0,0 +1,133 @@
+//! p9-fb-12: integration tests for `mode_intercept`. Drives the
+//! global i/Esc dispatch by constructing KeyEvents directly without
+//! standing up the full run loop (terminal-side).
+
+use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
+use kebab_config::Config;
+use kebab_tui::{App, Mode, Pane, mode_intercept};
+
+fn fresh_app(focus: Pane) -> App {
+    let mut config = Config::defaults();
+    config.storage.data_dir = "/tmp/kebab-tui-mode-tests-noop".to_string();
+    config.workspace.root = "/tmp/kebab-tui-mode-tests-noop/workspace".to_string();
+    let mut app = App::new(config).expect("App::new");
+    app.focus = focus;
+    app.mode = Mode::auto_for(focus);
+    app
+}
+
+/// p9-fb-12: `Esc` from Insert mode flips to Normal on any pane.
+/// Returns `true` (consumed) so the pane handler doesn't ALSO see
+/// the Esc as a "back to Library" signal.
+#[test]
+fn esc_in_insert_flips_to_normal_and_consumes() {
+    for &pane in &[Pane::Library, Pane::Search, Pane::Ask, Pane::Inspect] {
+        let mut app = fresh_app(pane);
+        app.mode = Mode::Insert;
+        let consumed = mode_intercept(
+            &mut app,
+            KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE),
+        );
+        assert!(consumed, "Esc in Insert must be consumed (pane: {pane:?})");
+        assert_eq!(app.mode, Mode::Normal, "mode flipped to Normal (pane: {pane:?})");
+    }
+}
+
+/// p9-fb-12: `Esc` from Normal mode is a no-op (not consumed) so the
+/// pane's existing Esc handler (e.g. Library `Esc` → quit) keeps
+/// working.
+#[test]
+fn esc_in_normal_mode_falls_through() {
+    let mut app = fresh_app(Pane::Library);
+    assert_eq!(app.mode, Mode::Normal);
+    let consumed = mode_intercept(
+        &mut app,
+        KeyEvent::new(KeyCode::Esc, KeyModifiers::NONE),
+    );
+    assert!(!consumed, "Esc in Normal must fall through to pane");
+    assert_eq!(app.mode, Mode::Normal, "mode unchanged");
+}
+
+/// p9-fb-12: `i` in Normal mode on Library / Inspect / Jobs flips
+/// to Insert. (`i` has no pre-fb-12 meaning on those panes, so the
+/// global interception is safe.)
+#[test]
+fn i_in_normal_on_library_inspect_jobs_flips_to_insert() {
+    for &pane in &[Pane::Library, Pane::Inspect, Pane::Jobs] {
+        let mut app = fresh_app(pane);
+        assert_eq!(app.mode, Mode::Normal, "auto_for({pane:?}) should be Normal");
+        let consumed = mode_intercept(
+            &mut app,
+            KeyEvent::new(KeyCode::Char('i'), KeyModifiers::NONE),
+        );
+        assert!(consumed, "i in Normal on {pane:?} must be consumed");
+        assert_eq!(app.mode, Mode::Insert, "mode flipped to Insert (pane: {pane:?})");
+    }
+}
+
+/// p9-fb-12: `i` on Search / Ask falls through (the pane is already
+/// in Insert via Mode::auto_for, so the global `i` interception
+/// would swallow what should be a typed character).
+#[test]
+fn i_on_search_or_ask_falls_through_to_pane() {
+    for &pane in &[Pane::Search, Pane::Ask] {
+        let mut app = fresh_app(pane);
+        assert_eq!(app.mode, Mode::Insert, "auto_for({pane:?}) should be Insert");
+        let consumed = mode_intercept(
+            &mut app,
+            KeyEvent::new(KeyCode::Char('i'), KeyModifiers::NONE),
+        );
+        assert!(!consumed, "i on {pane:?} must fall through to pane");
+        assert_eq!(app.mode, Mode::Insert, "mode unchanged");
+    }
+}
+
+/// p9-fb-12: modifier-bearing keys (Ctrl+Esc, Alt+i) are NOT the
+/// mode toggle. Falls through so chord handlers downstream get a
+/// shot.
+#[test]
+fn modifier_keys_do_not_trigger_intercept() {
+    let mut app = fresh_app(Pane::Library);
+    app.mode = Mode::Insert;
+    let consumed = mode_intercept(
+        &mut app,
+        KeyEvent::new(KeyCode::Esc, KeyModifiers::CONTROL),
+    );
+    assert!(!consumed, "Ctrl+Esc must fall through");
+    assert_eq!(app.mode, Mode::Insert, "mode unchanged");
+
+    app.mode = Mode::Normal;
+    let consumed = mode_intercept(
+        &mut app,
+        KeyEvent::new(KeyCode::Char('i'), KeyModifiers::ALT),
+    );
+    assert!(!consumed, "Alt+i must fall through");
+    assert_eq!(app.mode, Mode::Normal, "mode unchanged");
+}
+
+/// p9-fb-12: SHIFT alone is allowed (the toggle keys are unshifted
+/// `i` / `Esc`, but a future `Shift+Esc` chord is unlikely; pre-
+/// allow SHIFT so capital-letter typing in Search/Ask doesn't
+/// accidentally fall into the modifier-block branch).
+#[test]
+fn shift_modifier_passes_modifier_filter() {
+    // SHIFT+Esc is a strange combo but the filter passes it. (The
+    // actual outcome — does mode flip? — depends on the case
+    // matching i/Esc. SHIFT+Esc still matches KeyCode::Esc, so it
+    // toggles. SHIFT+I would be KeyCode::Char('I') (capital), NOT
+    // 'i', so it falls through. Both are intentional.)
+    let mut app = fresh_app(Pane::Library);
+    app.mode = Mode::Insert;
+    let consumed = mode_intercept(
+        &mut app,
+        KeyEvent::new(KeyCode::Esc, KeyModifiers::SHIFT),
+    );
+    assert!(consumed, "Shift+Esc still toggles (modifier filter allows SHIFT)");
+
+    let mut app = fresh_app(Pane::Library);
+    let consumed = mode_intercept(
+        &mut app,
+        KeyEvent::new(KeyCode::Char('I'), KeyModifiers::SHIFT),
+    );
+    assert!(!consumed, "Shift+I (capital) falls through — only lowercase 'i' toggles");
+}