feat(site): add Kyleosophy alternative completion chimes (#23891)

- Add "Enable Kyleosophy" toggle to Settings > Behavior
- When enabled, replaces standard completion chime with random Kyle
sound clips
- Ships 8 alternative `.mp3` files as static assets (~82KB total)
- localStorage preference (`agents.kyleosophy`), defaults to off
- Pauses orphaned Audio elements on sound URL change to prevent overlap

<details><summary>Review findings addressed</summary>

- **P2** Stale JSDoc on `playChimeAudio` — updated to reflect
parameterized behavior
- **P3** Overlapping audio on rapid completions — added
`chimeAudio?.pause()` before replacement
- **P3** Test ordering dependency — pinned `Math.random` for
determinism, documented cache behavior
- **Nit** Setter naming — `setLocalKyleosophy` → `setKylesophyLocal`
- Toggle moved to bottom of Behavior page per product request
- Description changed to "IYKYK" per product request

</details>

> 🤖 Written by a Coder Agent. Reviewed by a human.

site/src/pages/AgentsPage/AgentSettingsBehaviorPageView.tsx

@@ -13,6 +13,7 @@ import { DurationField } from "./components/DurationField/DurationField";
 import { SectionHeader } from "./components/SectionHeader";
 import { TextPreviewDialog } from "./components/TextPreviewDialog";
 import { UserCompactionThresholdSettings } from "./components/UserCompactionThresholdSettings";
+import { getKylesophyEnabled, setKylesophyEnabled } from "./utils/chime";
 
 const textareaMaxHeight = 240;
 const textareaBaseClassName =
@@ -124,6 +125,7 @@ export const AgentSettingsBehaviorPageView: FC<
 	const [isUserPromptOverflowing, setIsUserPromptOverflowing] = useState(false);
 	const [isSystemPromptOverflowing, setIsSystemPromptOverflowing] =
 		useState(false);
+	const [kylesophyEnabled, setKylesophyLocal] = useState(getKylesophyEnabled);
 
 	// ── Derived state ──
 	const hasLoadedSystemPrompt = systemPromptData !== undefined;
@@ -510,6 +512,26 @@ export const AgentSettingsBehaviorPageView: FC<
 					</form>
 				</>
 			)}
+			<hr className="my-5 border-0 border-t border-solid border-border" />
+			{/* ── Kyleosophy toggle (always visible) ── */}
+			<div className="space-y-2">
+				<h3 className="m-0 text-[13px] font-semibold text-content-primary">
+					Kyleosophy
+				</h3>
+				<div className="flex items-center justify-between gap-4">
+					<p className="!mt-0.5 m-0 flex-1 text-xs text-content-secondary">
+						Replace the standard completion chime. IYKYK.
+					</p>
+					<Switch
+						checked={kylesophyEnabled}
+						onCheckedChange={(checked) => {
+							setKylesophyEnabled(checked);
+							setKylesophyLocal(checked);
+						}}
+						aria-label="Enable Kyleosophy"
+					/>
+				</div>
+			</div>
 			{showDefaultPromptPreview && (
 				<TextPreviewDialog
 					content={defaultSystemPrompt}

site/src/pages/AgentsPage/utils/chime.test.ts

@@ -1,9 +1,12 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import {
 	getChimeEnabled,
+	getKylesophyEnabled,
+	KYLEOSOPHY_SOUNDS,
 	LOCK_HOLD_MS,
 	maybePlayChime,
 	setChimeEnabled,
+	setKylesophyEnabled,
 } from "./chime";
 
 // ---------------------------------------------------------------------------
@@ -69,6 +72,40 @@ describe("getChimeEnabled / setChimeEnabled", () => {
 	});
 });
 
+// ---------------------------------------------------------------------------
+// Kyleosophy preference helpers
+// ---------------------------------------------------------------------------
+
+describe("getKylesophyEnabled / setKylesophyEnabled", () => {
+	beforeEach(() => {
+		localStorage.clear();
+	});
+
+	it("defaults to false when nothing is stored", () => {
+		expect(getKylesophyEnabled()).toBe(false);
+	});
+
+	it("returns true when stored as 'true'", () => {
+		localStorage.setItem("agents.kyleosophy", "true");
+		expect(getKylesophyEnabled()).toBe(true);
+	});
+
+	it("returns false when stored as 'false'", () => {
+		localStorage.setItem("agents.kyleosophy", "false");
+		expect(getKylesophyEnabled()).toBe(false);
+	});
+
+	it("setKylesophyEnabled persists the value", () => {
+		setKylesophyEnabled(false);
+		expect(localStorage.getItem("agents.kyleosophy")).toBe("false");
+		expect(getKylesophyEnabled()).toBe(false);
+
+		setKylesophyEnabled(true);
+		expect(localStorage.getItem("agents.kyleosophy")).toBe("true");
+		expect(getKylesophyEnabled()).toBe(true);
+	});
+});
+
 // ---------------------------------------------------------------------------
 // maybePlayChime
 // ---------------------------------------------------------------------------
@@ -235,4 +272,44 @@ describe("maybePlayChime", () => {
 		// Should play immediately without needing to advance timers.
 		expect(playSpy).toHaveBeenCalledTimes(1);
 	});
+
+	// -- Kyleosophy sound selection --
+
+	it("uses a kyleosophy sound when kyleosophy is enabled", async () => {
+		setKylesophyEnabled(true);
+		vi.spyOn(document, "hidden", "get").mockReturnValue(true);
+		// Pin the random selection so the test is deterministic.
+		vi.spyOn(Math, "random").mockReturnValue(0.5);
+
+		const audioSpy = vi.spyOn(globalThis, "Audio" as never);
+
+		await triggerAndSettle("running", "waiting", "chat-1", "chat-2");
+		expect(playSpy).toHaveBeenCalledTimes(1);
+		expect(audioSpy).toHaveBeenCalledTimes(1);
+
+		const url = (audioSpy as unknown as ReturnType<typeof vi.fn>).mock
+			.calls[0][0] as string;
+		// Math.floor(0.5 * 8) = 4 → "/chime_5.mp3"
+		expect(url).toBe("/chime_5.mp3");
+		expect(KYLEOSOPHY_SOUNDS).toContain(url);
+	});
+
+	it("uses default chime.mp3 when kyleosophy is disabled", async () => {
+		setKylesophyEnabled(false);
+		vi.spyOn(document, "hidden", "get").mockReturnValue(true);
+
+		// Force a fresh Audio element by spying on the constructor
+		// before any call in this test. The previous test left
+		// lastSoundUrl pointing at a kyleosophy URL, so switching
+		// back to /chime.mp3 will always trigger a new Audio().
+		const audioSpy = vi.spyOn(globalThis, "Audio" as never);
+
+		await triggerAndSettle("running", "waiting", "chat-1", "chat-2");
+		expect(playSpy).toHaveBeenCalledTimes(1);
+		expect(audioSpy).toHaveBeenCalledTimes(1);
+
+		const url = (audioSpy as unknown as ReturnType<typeof vi.fn>).mock
+			.calls[0][0] as string;
+		expect(url).toBe("/chime.mp3");
+	});
 });

site/src/pages/AgentsPage/utils/chime.ts

@@ -1,4 +1,5 @@
 const CHIME_PREFERENCE_KEY = "agents.chime-on-completion";
+const KYLEOSOPHY_PREFERENCE_KEY = "agents.kyleosophy";
 
 export function getChimeEnabled(): boolean {
 	try {
@@ -19,20 +20,55 @@ export function setChimeEnabled(enabled: boolean): void {
 	}
 }
 
+export function getKylesophyEnabled(): boolean {
+	try {
+		const stored = localStorage.getItem(KYLEOSOPHY_PREFERENCE_KEY);
+		return stored === null ? false : stored === "true";
+	} catch {
+		return false;
+	}
+}
+
+export function setKylesophyEnabled(enabled: boolean): void {
+	try {
+		localStorage.setItem(KYLEOSOPHY_PREFERENCE_KEY, String(enabled));
+	} catch {
+		// Silently ignore storage errors (e.g. private browsing
+		// quota exceeded).
+	}
+}
+
 /**
- * Play the completion chime audio file. The file is a short,
- * warm two-tone bell sound shipped as a static asset.
- *
- * A single Audio element is reused across calls so the browser
- * only fetches the file once.
+ * Alternative completion sounds for Kyleosophy mode. All are
+ * shipped as static assets alongside chime.mp3.
+ */
+export const KYLEOSOPHY_SOUNDS: readonly string[] = [
+	"/chime_1.mp3", // absolutely massive
+	"/chime_2.mp3", // dope
+	"/chime_3.mp3", // great
+	"/chime_4.mp3", // oh god
+	"/chime_5.mp3", // okay
+	"/chime_6.mp3", // open up a pr
+	"/chime_7.mp3", // sweet
+	"/chime_8.mp3", // yep
+];
+
+/**
+ * Play a completion sound. When Kyleosophy is enabled a random
+ * voice clip is selected; otherwise the default bell chime is
+ * used. The Audio element is cached and reused when the sound
+ * URL hasn't changed between calls.
  */
 let chimeAudio: HTMLAudioElement | null = null;
+let lastSoundUrl: string | null = null;
 
-function playChimeAudio(): void {
+function playChimeAudio(soundUrl = "/chime.mp3"): void {
 	try {
-		if (!chimeAudio) {
-			chimeAudio = new Audio("/chime.mp3");
+		if (!chimeAudio || soundUrl !== lastSoundUrl) {
+			chimeAudio?.pause();
+			chimeAudio = new Audio(soundUrl);
 			chimeAudio.volume = 0.5;
+			lastSoundUrl = soundUrl;
 		}
 		// Reset to the start in case a previous play hasn't
 		// finished yet.
@@ -75,9 +111,9 @@ export const LOCK_HOLD_MS = 2000;
  * Falls back to playing immediately when the Web Locks API is
  * not available (preserving the original single-tab behavior).
  */
-function playChime(chatID: string): void {
+function playChime(chatID: string, soundUrl?: string): void {
 	if (typeof navigator === "undefined" || !navigator.locks) {
-		playChimeAudio();
+		playChimeAudio(soundUrl);
 		return;
 	}
 
@@ -93,7 +129,7 @@ function playChime(chatID: string): void {
 				return;
 			}
 
-			playChimeAudio();
+			playChimeAudio(soundUrl);
 
 			// Hold the lock briefly so that tabs receiving the
 			// WebSocket event a bit later will see the lock as
@@ -149,5 +185,9 @@ export function maybePlayChime(
 		return;
 	}
 
-	playChime(chatID);
+	const soundUrl = getKylesophyEnabled()
+		? KYLEOSOPHY_SOUNDS[Math.floor(Math.random() * KYLEOSOPHY_SOUNDS.length)]
+		: undefined;
+
+	playChime(chatID, soundUrl);
 }