fix(web): handle preset settings updates and empty choices

packages/client/ui-agent-preset/src/client/AgentPresetSeat.tsx

@@ -93,12 +93,12 @@ export function AgentPresetSeat({
     void load()
   }, [load])
 
+  const options = state.options.filter(option => developerTools || !requiresCodingTools(option))
+
   // Close a menu whose available choices just changed.
   useEffect(() => {
     setOpen(false)
-  }, [developerTools])
-
-  const options = state.options.filter(option => developerTools || !requiresCodingTools(option))
+  }, [developerTools, options.length])
 
   const chosen = state.options.find(option => option.id === state.current)
   const chosenText = chosen === undefined ? undefined : presetDisplayText(chosen, t)
@@ -152,7 +152,7 @@ export function AgentPresetSeat({
   return (
     <>
       <Menu
-        open={open}
+        open={open && options.length > 0}
         onClose={() => { setOpen(false) }}
         items={options.map((option) => {
           const text = presetDisplayText(option, t)
@@ -193,9 +193,9 @@ export function AgentPresetSeat({
             type="button"
             className={css.seat}
             aria-haspopup="menu"
-            aria-expanded={open}
+            aria-expanded={open && options.length > 0}
             title={state.error ?? t('seatHint')}
-            disabled={state.busy}
+            disabled={state.busy || options.length === 0}
             onClick={() => { setOpen(value => !value) }}
           >
             <IconAgentPresetOutlineRegular className={introducing ? `${css.seatIcon} ${css.introIcon}` : css.seatIcon} />

packages/client/ui-agent-preset/src/client/index.ts

@@ -135,12 +135,14 @@ export function apply(ctx: ClientContext): void {
     const reconcile = (): void => {
       requested++
       pending ??= Promise.resolve().then(async () => {
-        for (;;) {
-          const revision = requested
-          await section.reconcileCodingTools(codingToolsDisabled)
-          if (!active || requested === revision) return
-        }
-      }).finally(() => { pending = undefined })
+        try {
+          for (;;) {
+            const revision = requested
+            await section.reconcileCodingTools(codingToolsDisabled)
+            if (!active || requested === revision) return
+          }
+        } finally { pending = undefined }
+      })
     }
     // The roster reflects live declarations and the default is a settings field, so
     // both an external settings edit and a reconnect can move this row.

packages/client/ui-agent-preset/tests/apply.client.spec.ts

@@ -22,6 +22,7 @@ import type { AgentPresetSectionInjected } from '../src/client/AgentPresetSectio
 import { AgentPresetSeat } from '../src/client/AgentPresetSeat.tsx'
 import type { AgentPresetSeatInjected } from '../src/client/AgentPresetSeat.tsx'
 import { AgentPresetSeatController } from '../src/client/seat-store.ts'
+import { AgentPresetSectionController } from '../src/client/section-store.ts'
 import { apply as hostApply } from '../src/index.ts'
 import type { AgentPresetRow } from '@deepseek-ai/dsh-agent-preset-registry/types'
 
@@ -897,6 +898,38 @@ describe('ui-agent-preset apply', () => {
     await b.ctx.fiber.dispose()
   })
 
+  it('corrects a hidden default when accepted settings arrive as the previous reconciliation settles', async () => {
+    const b = await bench({ presets: ROSTER_MOVED.value.presets })
+    b.ctx.provide('sessions', sessionsDouble(b.ctx, { byId: {} }) as never)
+    declareRoot(b.slots)
+    const answer = await b.ctx.remote.settings.describe()
+    if (!answer.ok) throw new Error(answer.error.message)
+    const describe = vi.spyOn(b.ctx.remote.settings, 'describe').mockResolvedValue({
+      ...answer,
+      value: { ...answer.value, namespaces: answer.value.namespaces.map(row => row.ns === 'ui-settings'
+        ? { ...row, value: { enabled: false } } : row) },
+    })
+    const disabled = Promise.withResolvers<undefined>()
+    const reconcile = vi.spyOn(AgentPresetSectionController.prototype, 'reconcileCodingTools')
+      .mockImplementationOnce(function (this: AgentPresetSectionController, shouldReset) {
+        reconcile.mockRestore()
+        const result = this.reconcileCodingTools(shouldReset)
+        // The real settings mirror publishes its already-answered read while
+        // the prior reconciliation's promise is settling.
+        void result.then(() => { void b.setDeveloperTools(false).then(() => { disabled.resolve(undefined) }, disabled.reject) })
+        return result
+      })
+    try {
+      await b.ctx.plugin({ inject: [...inject], apply }).await()
+      await disabled.promise
+      expect(b.calls.filter(call => call.startsWith('settings:'))).toEqual(['settings:{"selectedDefault":"standard"}'])
+    } finally {
+      await b.ctx.fiber.dispose()
+      reconcile.mockRestore()
+      describe.mockRestore()
+    }
+  })
+
   it.each([['cordis', true], ['mine', true], ['ptc', true], ['minimal', true], ['ptc', false], ['minimal', false]] as const)(
     'resets only the default while the current task uses %s (blank: %s)', async (preset, blank) => {
       const b = await bench({ presets: [

packages/client/ui-agent-preset/tests/components.client.spec.tsx

@@ -69,7 +69,7 @@ function renderSeat(
     t: translate,
   } as AgentPresetSeatProps
   render(<AgentPresetSeat {...props} />)
-  return { ...actions, developerTools }
+  return { ...actions, developerTools, store }
 }
 
 function renderLabel(
@@ -114,6 +114,33 @@ describe('the new-session chip', () => {
     expect(screen.getByRole('menuitem', { name: /^My workflow/ })).toBeTruthy()
   })
 
+  it('keeps the current mode visible without opening a picker when all options are hidden', () => {
+    const actions = renderSeat({ current: 'minimal', options: [{ id: 'ptc' }, { id: 'minimal' }] }, undefined, undefined, false)
+    const trigger = screen.getByRole<HTMLButtonElement>('button', { name: en.presetMinimalName })
+    expect(trigger.disabled).toBe(true)
+    fireEvent.click(trigger)
+    expect(trigger.getAttribute('aria-expanded')).toBe('false')
+    expect(screen.queryByRole('menu')).toBeNull()
+    expect(actions.select).not.toHaveBeenCalled()
+  })
+
+  it('closes a picker when its last visible option disappears and keeps it closed when options return', () => {
+    const options = [{ id: 'minimal' }, { id: 'mine' }]
+    const actions = renderSeat({ current: 'minimal', options }, undefined, undefined, false)
+    const trigger = screen.getByRole<HTMLButtonElement>('button', { name: en.presetMinimalName })
+    fireEvent.click(trigger)
+    expect(screen.getByRole('menuitem', { name: /^mine/ })).toBeTruthy()
+    act(() => { actions.store.set({ ...actions.store.getSnapshot(), options: [{ id: 'ptc' }, { id: 'minimal' }] }) })
+    expect(trigger.disabled).toBe(true)
+    expect(trigger.getAttribute('aria-expanded')).toBe('false')
+    expect(screen.queryByRole('menu')).toBeNull()
+    act(() => { actions.store.set({ ...actions.store.getSnapshot(), options }) })
+    expect(trigger.disabled).toBe(false)
+    expect(trigger.getAttribute('aria-expanded')).toBe('false')
+    expect(screen.queryByRole('menu')).toBeNull()
+    expect(actions.select).not.toHaveBeenCalled()
+  })
+
   it('renders only for a Session retained by the main view', () => {
     renderSeat({}, undefined, {
       id: 's1', retainInfo: { referenceCount: 1, retainedBy: { mainView: 1 } },