diff --git a/apps/web/src/components/features/terminal/terminal.tsx b/apps/web/src/components/features/terminal/terminal.tsx
index cb763a9..0e9cec2 100644
--- a/apps/web/src/components/features/terminal/terminal.tsx
+++ b/apps/web/src/components/features/terminal/terminal.tsx
@@ -276,10 +276,17 @@ export const TerminalComponent = React.forwardRef<TerminalRef, TerminalProps>(
         lineHeight: 1.2,
         letterSpacing: 0,
         allowTransparency: false,
-        scrollback: 10000,
+        // This terminal only ever hosts full-screen TUI tools (pi-agent,
+        // opencode), which repaint in place in the normal buffer and do not
+        // use the alternate screen or mouse tracking. With scrollback, every
+        // repaint accumulates as history → a viewport scrollbar appears and
+        // the mouse-wheel scrolls through stale frames instead of the app.
+        // scrollback:0 keeps only the live viewport: no bar, no stale-frame
+        // wheel jank. (Scrollbar is also hidden via CSS for belt-and-suspenders.)
+        scrollback: 0,
         ignoreBracketedPasteMode: false,
-        fastScrollSensitivity: 5,
-        scrollSensitivity: 1,
+        fastScrollSensitivity: 0,
+        scrollSensitivity: 0,
         smoothScrollDuration: 0,
         theme: {
           background: "#1e1e1e",
diff --git a/apps/web/src/styles/utilities.css b/apps/web/src/styles/utilities.css
index c7c23a2..82670fb 100644
--- a/apps/web/src/styles/utilities.css
+++ b/apps/web/src/styles/utilities.css
@@ -938,6 +938,14 @@ a.nav-item,
 	overscroll-behavior: auto;
 	max-height: 100% !important;
 	width: 100% !important;
+	/* Full-screen TUI tools repaint in place; scrollback is 0 (see terminal.tsx).
+	   Hide the viewport scrollbar so it never appears or captures input. */
+	scrollbar-width: none;
+	-ms-overflow-style: none;
+}
+
+.terminal-container .xterm-viewport::-webkit-scrollbar {
+	display: none;
 }
 
 /* On mobile the custom touch handler scrolls the buffer; disable native