diff --git a/README.md b/README.md
index c7527928..6bcfbaab 100644
--- a/README.md
+++ b/README.md
@@ -483,8 +483,8 @@ Single-digit selection (1-9), color-coded status, token counts, auto-refresh. De
 |----------|--------|
 | `Ctrl/Cmd+W` | Kill active session |
 | `Ctrl/Cmd+Tab` | Next session |
-| `Option+[` / `Option+]` | Previous / next session |
-| `Option+1`-`Option+9` | Switch to tab N (physical keys, so macOS Option layouts work) |
+| `Alt/Option+[` / `Alt/Option+]` | Previous / next session |
+| `Alt/Option+1`-`Alt/Option+9` | Switch to tab N (physical keys, so macOS Option layouts work) |
 | `Ctrl+Shift+{` / `Ctrl+Shift+}` | Move active tab left / right |
 | `Ctrl/Cmd+L` | Clear terminal |
 | `Ctrl+Shift+R` | Restore terminal size |
diff --git a/src/web/public/index.html b/src/web/public/index.html
index 38194fb8..09588109 100644
--- a/src/web/public/index.html
+++ b/src/web/public/index.html
@@ -505,8 +505,8 @@
           <div class="shortcuts-grid">
             <div><kbd>Ctrl</kbd>+<kbd>W</kbd></div><div>Close Session</div>
             <div><kbd>Ctrl</kbd>+<kbd>Tab</kbd></div><div>Next Session</div>
-            <div><kbd>Option</kbd>+<kbd>[</kbd> / <kbd>Option</kbd>+<kbd>]</kbd></div><div>Previous / Next Session</div>
-            <div><kbd>Option</kbd>+<kbd>1-9</kbd></div><div>Switch to Tab N</div>
+            <div><kbd>Alt/Option</kbd>+<kbd>[</kbd> / <kbd>Alt/Option</kbd>+<kbd>]</kbd></div><div>Previous / Next Session</div>
+            <div><kbd>Alt/Option</kbd>+<kbd>1-9</kbd></div><div>Switch to Tab N</div>
             <div><kbd>Ctrl</kbd>+<kbd>L</kbd></div><div>Clear Terminal</div>
             <div><kbd>Ctrl</kbd>+<kbd>+</kbd></div><div>Increase Font</div>
             <div><kbd>Ctrl</kbd>+<kbd>-</kbd></div><div>Decrease Font</div>
diff --git a/src/web/public/terminal-ui.js b/src/web/public/terminal-ui.js
index c6edc476..c39f91a2 100644
--- a/src/web/public/terminal-ui.js
+++ b/src/web/public/terminal-ui.js
@@ -114,8 +114,14 @@ Object.assign(CodemanApp.prototype, {
     this.terminal.attachCustomKeyEventHandler((ev) => {
       if (ev.isComposing || ev.keyCode === 229) return false;
 
-      // Let Alt+digit pass through to browser (tab switching)
-      if (ev.altKey && ev.key >= '0' && ev.key <= '9') return false;
+      // Let the app's Alt/Option session-nav shortcuts reach the document keydown handler
+      // (app.js switches tabs by PHYSICAL e.code) instead of xterm injecting ESC<char> into
+      // the PTY. Mirror app.js's gate exactly — same physical codes + modifier guard — so
+      // macOS Option layouts (Option+1 -> "¡", Option+[ -> "“") are suppressed here too and
+      // don't leak an escape sequence into the focused terminal on every tab switch.
+      if (ev.altKey && !ev.ctrlKey && !ev.shiftKey && /^(Digit[1-9]|BracketLeft|BracketRight)$/.test(ev.code || '')) {
+        return false;
+      }
 
       // Ctrl+V / Cmd+V: intercept before xterm sends ^V to PTY.
       // Route through our paste trap which handles both images and text.
diff --git a/test/keyboard-shortcuts.test.ts b/test/keyboard-shortcuts.test.ts
index b02f43d6..7b93e541 100644
--- a/test/keyboard-shortcuts.test.ts
+++ b/test/keyboard-shortcuts.test.ts
@@ -2,6 +2,7 @@ import { readFileSync } from 'node:fs';
 import { describe, expect, it } from 'vitest';
 
 const appSource = readFileSync('src/web/public/app.js', 'utf8');
+const terminalUiSource = readFileSync('src/web/public/terminal-ui.js', 'utf8');
 const helpHtml = readFileSync('src/web/public/index.html', 'utf8');
 const readme = readFileSync('README.md', 'utf8');
 
@@ -19,11 +20,18 @@ describe('keyboard shortcuts', () => {
     expect(appSource).toContain('this.nextSession()');
   });
 
-  it('documents mac-friendly Option shortcuts in help and README', () => {
-    expect(helpHtml).toContain('<kbd>Option</kbd>+<kbd>[</kbd>');
-    expect(helpHtml).toContain('<kbd>Option</kbd>+<kbd>]</kbd>');
-    expect(helpHtml).toContain('<kbd>Option</kbd>+<kbd>1-9</kbd>');
-    expect(readme).toContain('`Option+[` / `Option+]`');
-    expect(readme).toContain('`Option+1`-`Option+9`');
+  it('suppresses xterm PTY injection for the same physical Alt nav codes (no ESC leak)', () => {
+    // terminal-ui.js must gate its xterm pass-through on the SAME physical e.code set the
+    // app.js handler consumes; otherwise Alt+[ / Alt+] (and Option+digit on remapped macOS
+    // layouts) switch tabs AND inject ESC<char> into the focused terminal. Keep in sync.
+    expect(terminalUiSource).toContain('/^(Digit[1-9]|BracketLeft|BracketRight)$/.test(ev.code');
+  });
+
+  it('documents the Alt/Option shortcuts in help and README', () => {
+    expect(helpHtml).toContain('<kbd>Alt/Option</kbd>+<kbd>[</kbd>');
+    expect(helpHtml).toContain('<kbd>Alt/Option</kbd>+<kbd>]</kbd>');
+    expect(helpHtml).toContain('<kbd>Alt/Option</kbd>+<kbd>1-9</kbd>');
+    expect(readme).toContain('`Alt/Option+[` / `Alt/Option+]`');
+    expect(readme).toContain('`Alt/Option+1`-`Alt/Option+9`');
   });
 });