diff --git a/apps/desktop/src/components/assistant-ui/message-render-boundary.test.tsx b/apps/desktop/src/components/assistant-ui/message-render-boundary.test.tsx
index 934f3babd1c0..8e1b70f7934f 100644
--- a/apps/desktop/src/components/assistant-ui/message-render-boundary.test.tsx
+++ b/apps/desktop/src/components/assistant-ui/message-render-boundary.test.tsx
@@ -13,7 +13,7 @@ function Boom({ error }: { error: Error | null }): null {
   return null
 }
 
-const lookupError = new Error('tapClientLookup: Index 2 out of bounds (length: 2)')
+const lookupError = new Error('useClientLookup: Index 2 out of bounds (length: 2)')
 
 describe('MessageRenderBoundary', () => {
   it('renders children when nothing throws', () => {
@@ -26,7 +26,7 @@ describe('MessageRenderBoundary', () => {
     expect(screen.getByText('content')).toBeTruthy()
   })
 
-  it('swallows the transient tapClientLookup out-of-bounds store race', () => {
+  it('swallows the transient useClientLookup out-of-bounds store race', () => {
     const spy = vi.spyOn(console, 'error').mockImplementation(() => undefined)
 
     const { container } = render(
diff --git a/apps/desktop/src/components/assistant-ui/message-render-boundary.tsx b/apps/desktop/src/components/assistant-ui/message-render-boundary.tsx
index 990f8c6072e4..f0fafbc4f18f 100644
--- a/apps/desktop/src/components/assistant-ui/message-render-boundary.tsx
+++ b/apps/desktop/src/components/assistant-ui/message-render-boundary.tsx
@@ -1,6 +1,6 @@
 import { Component, type ReactNode } from 'react'
 
-// `@assistant-ui/store`'s index-keyed child-scope lookup (`tapClientLookup`)
+// `@assistant-ui/store`'s index-keyed child-scope lookup (`useClientLookup`)
 // throws — rather than returning undefined — when a subscriber reads an index
 // that the message/parts list no longer has. This races during high-frequency
 // store replacement (session switch mid-stream, gateway reconnect replay): a
@@ -10,7 +10,7 @@ import { Component, type ReactNode } from 'react'
 // without a local boundary it unwinds to the root and blanks the whole app.
 // Upstream-tracked: assistant-ui/assistant-ui#4051, #3652.
 const isTransientLookupError = (error: unknown): boolean =>
-  error instanceof Error && /tapClient(Lookup|Resource).*out of bounds/.test(error.message)
+  error instanceof Error && /(useClientLookup|tapClient(Lookup|Resource)).*out of bounds/.test(error.message)
 
 interface Props {
   // Changes whenever the message list mutates; remounting clears the caught