fix(windows): preserve semantic escape key taps

2 files changed, 47 insertions, 0 deletions

diff --git a/docs/next/CHANGELOG.md b/docs/next/CHANGELOG.md
index 50632738..17ee1a24 100644
--- a/docs/next/CHANGELOG.md
+++ b/docs/next/CHANGELOG.md
@@ -28,6 +28,7 @@
 - OMP integration install, status, and uninstall now respect `PI_CONFIG_DIR` when `PI_CODING_AGENT_DIR` is not set, and installation refuses extension-directory collisions with Pi. (#1696)
 - Physical Escape key records on native Windows now bypass raw VT report framing, so pane applications receive Escape immediately and reliably. (#1736)
 - Native Windows key presses, grouped repeats, and releases now preserve their physical lifecycle and stay with the pane that received the initial press. (#2077)
+- Windows `pane send-keys` and `agent send-keys` now deliver semantic Escape as a complete key tap, preventing a following key from being interpreted as an Alt chord.
 - Windows now shows `system` notifications and completes MP3 notification sounds without leaving PowerShell players waiting for a timeout. (#1330)
 
 ## [0.7.5] - 2026-07-21
diff --git a/src/platform/windows.rs b/src/platform/windows.rs
index 6cc642eb..f384ea02 100644
--- a/src/platform/windows.rs
+++ b/src/platform/windows.rs
@@ -76,6 +76,12 @@ pub(crate) fn encode_windows_conpty_fallback(key: &crate::input::TerminalKey) ->
                 record.unicode,
                 record.control_key_state,
             )
+        } else if key.code == KeyCode::Esc
+            && key.modifiers.is_empty()
+            && key.kind == KeyEventKind::Press
+            && key.vt_bytes().is_none()
+        {
+            return Some(b"\x1b[27;1;27;1;0;1_\x1b[27;1;27;0;0;1_".to_vec());
         } else if key.code == KeyCode::Enter && key.modifiers == KeyModifiers::SHIFT {
             (13, 28, 13, 16)
         } else {
@@ -1435,6 +1441,46 @@ mod tests {
     }
 
     #[test]
+    fn windows_conpty_native_encoder_preserves_semantic_escape_fallback() {
+        let escape = crate::input::TerminalKey::new(
+            crossterm::event::KeyCode::Esc,
+            crossterm::event::KeyModifiers::empty(),
+        );
+
+        assert_eq!(
+            super::encode_windows_conpty_fallback(&escape),
+            Some(b"\x1b[27;1;27;1;0;1_\x1b[27;1;27;0;0;1_".to_vec())
+        );
+        assert_eq!(
+            super::encode_windows_conpty_fallback(
+                &escape
+                    .clone()
+                    .with_kind(crossterm::event::KeyEventKind::Repeat),
+            ),
+            None
+        );
+        assert_eq!(
+            super::encode_windows_conpty_fallback(
+                &escape
+                    .clone()
+                    .with_kind(crossterm::event::KeyEventKind::Release),
+            ),
+            None
+        );
+        assert_eq!(
+            super::encode_windows_conpty_fallback(&escape.clone().with_vt_bytes(vec![27])),
+            None
+        );
+        assert_eq!(
+            super::encode_windows_conpty_fallback(&crate::input::TerminalKey::new(
+                crossterm::event::KeyCode::Esc,
+                crossterm::event::KeyModifiers::ALT,
+            ),),
+            None
+        );
+    }
+
+    #[test]
     fn windows_conpty_native_encoder_preserves_semantic_shift_enter_fallback() {
         let shift_enter = crate::input::TerminalKey::new(
             crossterm::event::KeyCode::Enter,