diff --git a/apps/web/src/app/(sandbox)/sessions/[sessionId]/SessionReadTracker.tsx b/apps/web/src/app/(sandbox)/sessions/[sessionId]/SessionReadTracker.tsx
index 92a557cae..58717a7c4 100644
--- a/apps/web/src/app/(sandbox)/sessions/[sessionId]/SessionReadTracker.tsx
+++ b/apps/web/src/app/(sandbox)/sessions/[sessionId]/SessionReadTracker.tsx
@@ -4,7 +4,6 @@ import { useEffect } from 'react';
 
 import { useMarkSessionRead } from '@/hooks/useMarkSessionRead';
 import { useRecentSessions } from '@/hooks/useRecentSessions';
-import { useSessionPresence } from '@/hooks/useSessionPresence';
 import { useTelemetry } from '@/hooks/useTelemetry';
 
 export function SessionReadTracker({ sessionId }: { sessionId: string }) {
@@ -12,7 +11,6 @@ export function SessionReadTracker({ sessionId }: { sessionId: string }) {
   const { capture } = useTelemetry();
 
   useMarkSessionRead(sessionId);
-  useSessionPresence(sessionId);
 
   useEffect(() => {
     recordVisit(sessionId);
diff --git a/apps/web/src/app/api/sessions/[sessionId]/presence/route.test.ts b/apps/web/src/app/api/sessions/[sessionId]/presence/route.test.ts
deleted file mode 100644
index fa968cd83..000000000
--- a/apps/web/src/app/api/sessions/[sessionId]/presence/route.test.ts
+++ /dev/null
@@ -1,103 +0,0 @@
-import { NextRequest } from 'next/server';
-
-const {
-  authorizeMock,
-  disconnectSessionPresenceMock,
-  findAccessibleSessionMock,
-  refreshSessionPresenceMock,
-} = vi.hoisted(() => ({
-  authorizeMock: vi.fn(),
-  disconnectSessionPresenceMock: vi.fn(),
-  findAccessibleSessionMock: vi.fn(),
-  refreshSessionPresenceMock: vi.fn(),
-}));
-
-vi.mock('@/lib/server/auth-context', () => ({ authorize: authorizeMock }));
-vi.mock('@/lib/server/sessions', () => ({
-  findAccessibleSession: findAccessibleSessionMock,
-}));
-vi.mock('@roomote/redis', () => ({
-  disconnectSessionPresence: disconnectSessionPresenceMock,
-  refreshSessionPresence: refreshSessionPresenceMock,
-}));
-
-import { DELETE, POST } from './route';
-
-const SESSION_ID = '6a1f8f1e-0000-4000-8000-000000000006';
-const CLIENT_ID = '6a1f8f1e-0000-4000-8000-000000000007';
-const USER_ID = '6a1f8f1e-0000-4000-8000-000000000008';
-
-function request(method: 'POST' | 'DELETE', clientId = CLIENT_ID) {
-  return new NextRequest(
-    `http://localhost/api/sessions/${SESSION_ID}/presence`,
-    {
-      method,
-      headers: { 'content-type': 'application/json' },
-      body: JSON.stringify({ clientId }),
-    },
-  );
-}
-
-const props = { params: Promise.resolve({ sessionId: SESSION_ID }) };
-
-describe('/api/sessions/[sessionId]/presence', () => {
-  beforeEach(() => {
-    vi.clearAllMocks();
-    authorizeMock.mockResolvedValue({
-      success: true,
-      userId: USER_ID,
-      isAdmin: false,
-    });
-    findAccessibleSessionMock.mockResolvedValue({ id: SESSION_ID });
-    refreshSessionPresenceMock.mockResolvedValue({ expiresAt: 31_000 });
-  });
-
-  it('activates presence for the authenticated user and accessible Session', async () => {
-    const response = await POST(request('POST'), props);
-
-    expect(response.status).toBe(200);
-    await expect(response.json()).resolves.toEqual({ expiresAt: 31_000 });
-    expect(refreshSessionPresenceMock).toHaveBeenCalledWith({
-      sessionId: SESSION_ID,
-      userId: USER_ID,
-      clientId: CLIENT_ID,
-    });
-  });
-
-  it('disconnects the authenticated tab lease', async () => {
-    const response = await DELETE(request('DELETE'), props);
-
-    expect(response.status).toBe(204);
-    expect(disconnectSessionPresenceMock).toHaveBeenCalledWith({
-      sessionId: SESSION_ID,
-      userId: USER_ID,
-      clientId: CLIENT_ID,
-    });
-  });
-
-  it('rejects unauthenticated requests', async () => {
-    authorizeMock.mockResolvedValue({ success: false });
-
-    const response = await POST(request('POST'), props);
-
-    expect(response.status).toBe(401);
-    expect(findAccessibleSessionMock).not.toHaveBeenCalled();
-    expect(refreshSessionPresenceMock).not.toHaveBeenCalled();
-  });
-
-  it('does not create presence for an inaccessible Session', async () => {
-    findAccessibleSessionMock.mockResolvedValue(null);
-
-    const response = await POST(request('POST'), props);
-
-    expect(response.status).toBe(404);
-    expect(refreshSessionPresenceMock).not.toHaveBeenCalled();
-  });
-
-  it('rejects malformed client identifiers', async () => {
-    const response = await POST(request('POST', 'not-a-uuid'), props);
-
-    expect(response.status).toBe(400);
-    expect(findAccessibleSessionMock).not.toHaveBeenCalled();
-  });
-});
diff --git a/apps/web/src/app/api/sessions/[sessionId]/presence/route.ts b/apps/web/src/app/api/sessions/[sessionId]/presence/route.ts
deleted file mode 100644
index 3266f399c..000000000
--- a/apps/web/src/app/api/sessions/[sessionId]/presence/route.ts
+++ /dev/null
@@ -1,85 +0,0 @@
-import { type NextRequest, NextResponse } from 'next/server';
-import { z } from 'zod';
-
-import {
-  disconnectSessionPresence,
-  refreshSessionPresence,
-} from '@roomote/redis';
-
-import { authorize } from '@/lib/server/auth-context';
-import { findAccessibleSession } from '@/lib/server/sessions';
-
-export const runtime = 'nodejs';
-
-const paramsSchema = z.object({ sessionId: z.string().uuid() });
-const bodySchema = z.object({ clientId: z.string().uuid() });
-
-async function authorizePresenceRequest(
-  request: NextRequest,
-  props: { params: Promise<{ sessionId: string }> },
-) {
-  const auth = await authorize();
-  if (!auth.success) {
-    return {
-      success: false as const,
-      response: NextResponse.json({ error: 'Unauthorized' }, { status: 401 }),
-    };
-  }
-
-  const params = paramsSchema.safeParse(await props.params);
-  const body = bodySchema.safeParse(await request.json().catch(() => null));
-  if (!params.success || !body.success) {
-    return {
-      success: false as const,
-      response: NextResponse.json(
-        { error: 'Invalid request' },
-        { status: 400 },
-      ),
-    };
-  }
-
-  const session = await findAccessibleSession(auth, params.data.sessionId);
-  if (!session) {
-    return {
-      success: false as const,
-      response: NextResponse.json({ error: 'Not Found' }, { status: 404 }),
-    };
-  }
-
-  return {
-    success: true as const,
-    auth,
-    clientId: body.data.clientId,
-    sessionId: session.id,
-  };
-}
-
-export async function POST(
-  request: NextRequest,
-  props: { params: Promise<{ sessionId: string }> },
-) {
-  const context = await authorizePresenceRequest(request, props);
-  if (!context.success) return context.response;
-
-  const lease = await refreshSessionPresence({
-    sessionId: context.sessionId,
-    userId: context.auth.userId,
-    clientId: context.clientId,
-  });
-  return NextResponse.json(lease);
-}
-
-export async function DELETE(
-  request: NextRequest,
-  props: { params: Promise<{ sessionId: string }> },
-) {
-  const context = await authorizePresenceRequest(request, props);
-  if (!context.success) return context.response;
-
-  await disconnectSessionPresence({
-    sessionId: context.sessionId,
-    userId: context.auth.userId,
-    clientId: context.clientId,
-  });
-  return new NextResponse(null, { status: 204 });
-}
diff --git a/apps/web/src/hooks/useSessionPresence.client.test.tsx b/apps/web/src/hooks/useSessionPresence.client.test.tsx
deleted file mode 100644
index 68fac26df..000000000
--- a/apps/web/src/hooks/useSessionPresence.client.test.tsx
+++ /dev/null
@@ -1,110 +0,0 @@
-import { act, renderHook } from '@testing-library/react';
-
-import { useSessionPresence } from './useSessionPresence';
-
-const SESSION_ID = '6a1f8f1e-0000-4000-8000-000000000006';
-const CLIENT_ID = '6a1f8f1e-0000-4000-8000-000000000007';
-
-describe('useSessionPresence', () => {
-  const fetchMock = vi.fn().mockResolvedValue(new Response());
-  let focused = true;
-  let visibilityState: DocumentVisibilityState = 'visible';
-
-  beforeEach(() => {
-    vi.useFakeTimers();
-    vi.stubGlobal('fetch', fetchMock);
-    vi.spyOn(crypto, 'randomUUID').mockReturnValue(CLIENT_ID);
-    vi.spyOn(document, 'hasFocus').mockImplementation(() => focused);
-    Object.defineProperty(document, 'visibilityState', {
-      configurable: true,
-      get: () => visibilityState,
-    });
-    focused = true;
-    visibilityState = 'visible';
-    fetchMock.mockClear();
-  });
-
-  afterEach(() => {
-    vi.useRealTimers();
-    vi.restoreAllMocks();
-    vi.unstubAllGlobals();
-  });
-
-  it('activates immediately and refreshes while visible and focused', () => {
-    renderHook(() => useSessionPresence(SESSION_ID));
-
-    expect(fetchMock).toHaveBeenCalledTimes(1);
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'POST' }),
-    );
-
-    act(() => vi.advanceTimersByTime(20_000));
-    expect(fetchMock).toHaveBeenCalledTimes(3);
-  });
-
-  it('disconnects when attention leaves and starts a fresh heartbeat cycle on return', () => {
-    renderHook(() => useSessionPresence(SESSION_ID));
-
-    focused = false;
-    act(() => window.dispatchEvent(new Event('blur')));
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'DELETE' }),
-    );
-
-    act(() => vi.advanceTimersByTime(20_000));
-    expect(fetchMock).toHaveBeenCalledTimes(2);
-
-    focused = true;
-    act(() => window.dispatchEvent(new Event('focus')));
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'POST' }),
-    );
-  });
-
-  it('disconnects on page hide and unmount', () => {
-    const { unmount } = renderHook(() => useSessionPresence(SESSION_ID));
-
-    act(() => window.dispatchEvent(new Event('pagehide')));
-    expect(fetchMock).toHaveBeenCalledTimes(2);
-
-    focused = true;
-    act(() => window.dispatchEvent(new Event('focus')));
-    unmount();
-
-    expect(fetchMock).toHaveBeenCalledTimes(4);
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'DELETE' }),
-    );
-  });
-
-  it('restores presence when returning from the back-forward cache', () => {
-    renderHook(() => useSessionPresence(SESSION_ID));
-
-    act(() => window.dispatchEvent(new Event('pagehide')));
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'DELETE' }),
-    );
-
-    act(() => window.dispatchEvent(new Event('pageshow')));
-    expect(fetchMock).toHaveBeenLastCalledWith(
-      `/api/sessions/${SESSION_ID}/presence`,
-      expect.objectContaining({ method: 'POST' }),
-    );
-
-    act(() => vi.advanceTimersByTime(10_000));
-    expect(fetchMock).toHaveBeenCalledTimes(4);
-  });
-
-  it('does not activate from a hidden tab', () => {
-    visibilityState = 'hidden';
-
-    renderHook(() => useSessionPresence(SESSION_ID));
-
-    expect(fetchMock).not.toHaveBeenCalled();
-  });
-});
diff --git a/apps/web/src/hooks/useSessionPresence.ts b/apps/web/src/hooks/useSessionPresence.ts
deleted file mode 100644
index 54258f657..000000000
--- a/apps/web/src/hooks/useSessionPresence.ts
+++ /dev/null
@@ -1,62 +0,0 @@
-'use client';
-
-import { useEffect } from 'react';
-
-const HEARTBEAT_INTERVAL_MS = 10_000;
-
-export function useSessionPresence(sessionId: string) {
-  useEffect(() => {
-    const clientId = crypto.randomUUID();
-    const url = `/api/sessions/${sessionId}/presence`;
-    let heartbeatInterval: ReturnType<typeof setInterval> | undefined;
-    let active = false;
-
-    const send = (method: 'POST' | 'DELETE') => {
-      void fetch(url, {
-        method,
-        headers: { 'content-type': 'application/json' },
-        body: JSON.stringify({ clientId }),
-        keepalive: true,
-      }).catch(() => undefined);
-    };
-    const disconnect = () => {
-      if (!active) return;
-      active = false;
-      if (heartbeatInterval) clearInterval(heartbeatInterval);
-      heartbeatInterval = undefined;
-      send('DELETE');
-    };
-    const syncPresence = () => {
-      const viewing =
-        document.visibilityState === 'visible' && document.hasFocus();
-      if (!viewing) {
-        disconnect();
-        return;
-      }
-      if (active) return;
-
-      active = true;
-      send('POST');
-      heartbeatInterval = setInterval(
-        () => send('POST'),
-        HEARTBEAT_INTERVAL_MS,
-      );
-    };
-
-    syncPresence();
-    window.addEventListener('focus', syncPresence);
-    window.addEventListener('pageshow', syncPresence);
-    window.addEventListener('blur', disconnect);
-    window.addEventListener('pagehide', disconnect);
-    document.addEventListener('visibilitychange', syncPresence);
-
-    return () => {
-      window.removeEventListener('focus', syncPresence);
-      window.removeEventListener('pageshow', syncPresence);
-      window.removeEventListener('blur', disconnect);
-      window.removeEventListener('pagehide', disconnect);
-      document.removeEventListener('visibilitychange', syncPresence);
-      disconnect();
-    };
-  }, [sessionId]);
-}
diff --git a/packages/redis/src/__tests__/session-presence.test.ts b/packages/redis/src/__tests__/session-presence.test.ts
deleted file mode 100644
index 18817d79d..000000000
--- a/packages/redis/src/__tests__/session-presence.test.ts
+++ /dev/null
@@ -1,152 +0,0 @@
-import type { Redis } from 'ioredis';
-
-import {
-  disconnectSessionPresence,
-  isSessionUserPresent,
-  refreshSessionPresence,
-  SESSION_PRESENCE_LEASE_MS,
-} from '../session-presence';
-
-class PresenceRedis {
-  private readonly sets = new Map<string, Map<string, number>>();
-
-  multi() {
-    const operations: Array<() => void> = [];
-    const chain = {
-      zadd: (key: string, score: number, member: string) => {
-        operations.push(() => this.zadd(key, score, member));
-        return chain;
-      },
-      zremrangebyscore: (key: string, min: string, max: number) => {
-        operations.push(() => this.zremrangebyscore(key, min, max));
-        return chain;
-      },
-      pexpire: () => chain,
-      exec: async () => {
-        operations.forEach((operation) => operation());
-        return [];
-      },
-    };
-    return chain;
-  }
-
-  zadd(key: string, score: number, member: string) {
-    const set = this.sets.get(key) ?? new Map<string, number>();
-    set.set(member, score);
-    this.sets.set(key, set);
-    return 1;
-  }
-
-  async zrem(key: string, member: string) {
-    return this.sets.get(key)?.delete(member) ? 1 : 0;
-  }
-
-  async zremrangebyscore(key: string, _min: string, max: number) {
-    const set = this.sets.get(key);
-    if (!set) return 0;
-    let removed = 0;
-    for (const [member, score] of set) {
-      if (score <= max) {
-        set.delete(member);
-        removed += 1;
-      }
-    }
-    return removed;
-  }
-
-  async zcard(key: string) {
-    return this.sets.get(key)?.size ?? 0;
-  }
-}
-
-const identity = { sessionId: 'session-1', userId: 'user-1' };
-
-describe('Session presence leases', () => {
-  let redis: Redis;
-
-  beforeEach(() => {
-    redis = new PresenceRedis() as unknown as Redis;
-  });
-
-  it('activates presence and expires it after the lease deadline', async () => {
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { now: 1_000, redis },
-    );
-
-    await expect(
-      isSessionUserPresent(identity, { now: 1_000, redis }),
-    ).resolves.toBe(true);
-    await expect(
-      isSessionUserPresent(identity, {
-        now: 1_000 + SESSION_PRESENCE_LEASE_MS,
-        redis,
-      }),
-    ).resolves.toBe(false);
-  });
-
-  it('refreshes a tab lease from the latest heartbeat', async () => {
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { now: 1_000, redis },
-    );
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { now: 20_000, redis },
-    );
-
-    await expect(
-      isSessionUserPresent(identity, { now: 35_000, redis }),
-    ).resolves.toBe(true);
-    await expect(
-      isSessionUserPresent(identity, { now: 50_000, redis }),
-    ).resolves.toBe(false);
-  });
-
-  it('disconnects only the specified tab', async () => {
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { now: 1_000, redis },
-    );
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-2' },
-      { now: 1_000, redis },
-    );
-
-    await disconnectSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { redis },
-    );
-    await expect(
-      isSessionUserPresent(identity, { now: 1_000, redis }),
-    ).resolves.toBe(true);
-
-    await disconnectSessionPresence(
-      { ...identity, clientId: 'tab-2' },
-      { redis },
-    );
-    await expect(
-      isSessionUserPresent(identity, { now: 1_000, redis }),
-    ).resolves.toBe(false);
-  });
-
-  it('isolates leases between users and Sessions', async () => {
-    await refreshSessionPresence(
-      { ...identity, clientId: 'tab-1' },
-      { now: 1_000, redis },
-    );
-
-    await expect(
-      isSessionUserPresent(
-        { sessionId: 'session-2', userId: identity.userId },
-        { now: 1_000, redis },
-      ),
-    ).resolves.toBe(false);
-    await expect(
-      isSessionUserPresent(
-        { sessionId: identity.sessionId, userId: 'user-2' },
-        { now: 1_000, redis },
-      ),
-    ).resolves.toBe(false);
-  });
-});
diff --git a/packages/redis/src/index.ts b/packages/redis/src/index.ts
index 24b63d795..d6548dc54 100644
--- a/packages/redis/src/index.ts
+++ b/packages/redis/src/index.ts
@@ -2,12 +2,6 @@ import type { Redis } from 'ioredis';
 
 export type { Redis } from 'ioredis';
 export { getRedis } from './client';
-export {
-  disconnectSessionPresence,
-  isSessionUserPresent,
-  refreshSessionPresence,
-  SESSION_PRESENCE_LEASE_MS,
-} from './session-presence';
 
 export const REDIS_KEYS = {
   MENTIONED_THREADS: 'slack:mentioned_threads',
diff --git a/packages/redis/src/session-presence.ts b/packages/redis/src/session-presence.ts
deleted file mode 100644
index 38e5bade2..000000000
--- a/packages/redis/src/session-presence.ts
+++ /dev/null
@@ -1,65 +0,0 @@
-import type { Redis } from 'ioredis';
-
-import { getRedis } from './client';
-
-export const SESSION_PRESENCE_LEASE_MS = 30_000;
-
-type SessionPresenceIdentity = {
-  sessionId: string;
-  userId: string;
-};
-
-type SessionPresenceLease = SessionPresenceIdentity & {
-  clientId: string;
-};
-
-type SessionPresenceOptions = {
-  now?: number;
-  redis?: Redis;
-};
-
-function sessionPresenceKey({ sessionId, userId }: SessionPresenceIdentity) {
-  return `session:presence:${sessionId}:${userId}`;
-}
-
-/** Refreshes one browser tab's short-lived presence lease. */
-export async function refreshSessionPresence(
-  lease: SessionPresenceLease,
-  options: SessionPresenceOptions = {},
-): Promise<{ expiresAt: number }> {
-  const now = options.now ?? Date.now();
-  const expiresAt = now + SESSION_PRESENCE_LEASE_MS;
-  const redis = options.redis ?? getRedis();
-  const key = sessionPresenceKey(lease);
-
-  await redis
-    .multi()
-    .zadd(key, expiresAt, lease.clientId)
-    .zremrangebyscore(key, '-inf', now)
-    .pexpire(key, SESSION_PRESENCE_LEASE_MS * 2)
-    .exec();
-
-  return { expiresAt };
-}
-
-/** Best-effort immediate release; lease expiry remains the disconnect fallback. */
-export async function disconnectSessionPresence(
-  lease: SessionPresenceLease,
-  options: Pick<SessionPresenceOptions, 'redis'> = {},
-): Promise<void> {
-  const redis = options.redis ?? getRedis();
-  await redis.zrem(sessionPresenceKey(lease), lease.clientId);
-}
-
-/** Returns whether the user has any unexpired browser-tab lease for a Session. */
-export async function isSessionUserPresent(
-  identity: SessionPresenceIdentity,
-  options: SessionPresenceOptions = {},
-): Promise<boolean> {
-  const now = options.now ?? Date.now();
-  const redis = options.redis ?? getRedis();
-  const key = sessionPresenceKey(identity);
-
-  await redis.zremrangebyscore(key, '-inf', now);
-  return (await redis.zcard(key)) > 0;
-}