feat: searchable timezone select & bot timezone priority

- Add reusable TimezoneSelect component with search and UTC offset labels
- Replace plain Select with searchable TimezoneSelect in profile settings,
  bot settings, and browser context settings
- Move bot timezone setting from header dialog into bot settings tab
- Resolve timezone with bot > user > system priority for all LLM-facing
  time formatting (user message header, system prompt, heartbeat, tools,
  memory extraction)
- Format tool output timestamps (history, contacts) in resolved timezone

apps/web/src/components/timezone-select/index.vue

@@ -0,0 +1,63 @@
+<template>
+  <SearchableSelectPopover
+    v-model="selected"
+    :options="options"
+    :placeholder="placeholder || ''"
+    :aria-label="placeholder || 'Select timezone'"
+    :search-placeholder="$t('common.searchTimezone')"
+    search-aria-label="Search timezones"
+    :empty-text="$t('common.noTimezoneFound')"
+    :show-group-headers="false"
+  />
+</template>
+
+<script setup lang="ts">
+import { computed } from 'vue'
+import { useI18n } from 'vue-i18n'
+import SearchableSelectPopover from '@/components/searchable-select-popover/index.vue'
+import type { SearchableSelectOption } from '@/components/searchable-select-popover/index.vue'
+import { timezones, emptyTimezoneValue, getUtcOffsetLabel } from '@/utils/timezones'
+
+const { t } = useI18n()
+
+const props = withDefaults(defineProps<{
+  placeholder?: string
+  allowEmpty?: boolean
+  emptyLabel?: string
+}>(), {
+  placeholder: '',
+  allowEmpty: false,
+  emptyLabel: '',
+})
+
+const selected = defineModel<string>({ default: '' })
+
+const offsetMap = computed(() => {
+  const map = new Map<string, string>()
+  for (const tz of timezones) {
+    map.set(tz, getUtcOffsetLabel(tz))
+  }
+  return map
+})
+
+const options = computed<SearchableSelectOption[]>(() => {
+  const items: SearchableSelectOption[] = []
+  if (props.allowEmpty) {
+    items.push({
+      value: emptyTimezoneValue,
+      label: props.emptyLabel || t('bots.timezoneInherited'),
+    })
+  }
+  for (const tz of timezones) {
+    const parts = tz.split('/')
+    const offset = offsetMap.value.get(tz) ?? ''
+    items.push({
+      value: tz,
+      label: tz,
+      description: offset,
+      keywords: [...parts, offset],
+    })
+  }
+  return items
+})
+</script>

apps/web/src/i18n/locales/en.json

@@ -34,7 +34,9 @@
     "loadFailed": "Failed to load",
     "saveFailed": "Failed to save",
     "createdAt": "Created at",
-    "none": "None"
+    "none": "None",
+    "searchTimezone": "Search timezones…",
+    "noTimezoneFound": "No timezone found."
   },
   "auth": {
     "welcome": "Welcome Back",

apps/web/src/i18n/locales/zh.json

@@ -34,7 +34,9 @@
     "loadFailed": "加载失败",
     "saveFailed": "保存失败",
     "createdAt": "创建时间",
-    "none": "无"
+    "none": "无",
+    "searchTimezone": "搜索时区…",
+    "noTimezoneFound": "未找到时区"
   },
   "auth": {
     "welcome": "欢迎回来",

apps/web/src/pages/bots/components/bot-settings.vue

@@ -197,6 +197,21 @@
       />
     </div>
 
+    <!-- Timezone -->
+    <div class="space-y-2">
+      <Label>{{ $t('bots.timezone') }}</Label>
+      <TimezoneSelect
+        :model-value="timezoneModel"
+        :placeholder="$t('bots.timezonePlaceholder')"
+        allow-empty
+        :empty-label="$t('bots.timezoneInherited')"
+        @update:model-value="onTimezoneChange"
+      />
+      <p class="text-xs text-muted-foreground">
+        {{ $t('bots.timezoneInheritedHint') }}
+      </p>
+    </div>
+
     <Separator />
 
     <!-- Max Context Load Time -->
@@ -334,18 +349,20 @@ import {
   SelectTrigger,
   SelectValue,
 } from '@memohai/ui'
-import { reactive, computed, watch } from 'vue'
+import { reactive, computed, watch, ref } from 'vue'
 import { useRouter } from 'vue-router'
 import { toast } from 'vue-sonner'
 import { useI18n } from 'vue-i18n'
 import ConfirmPopover from '@/components/confirm-popover/index.vue'
+import TimezoneSelect from '@/components/timezone-select/index.vue'
+import { emptyTimezoneValue } from '@/utils/timezones'
 import ModelSelect from './model-select.vue'
 import SearchProviderSelect from './search-provider-select.vue'
 import MemoryProviderSelect from './memory-provider-select.vue'
 import TtsModelSelect from './tts-model-select.vue'
 import BrowserContextSelect from './browser-context-select.vue'
 import { useQuery, useMutation, useQueryCache } from '@pinia/colada'
-import { getBotsByBotIdSettings, putBotsByBotIdSettings, deleteBotsById, getModels, getProviders, getSearchProviders, getMemoryProviders, getTtsProviders, getBrowserContexts, getBotsByBotIdMemoryStatus, postBotsByBotIdMemoryRebuild } from '@memohai/sdk'
+import { getBotsById, putBotsById, getBotsByBotIdSettings, putBotsByBotIdSettings, deleteBotsById, getModels, getProviders, getSearchProviders, getMemoryProviders, getTtsProviders, getBrowserContexts, getBotsByBotIdMemoryStatus, postBotsByBotIdMemoryRebuild } from '@memohai/sdk'
 import type { SettingsSettings } from '@memohai/sdk'
 import type { Ref } from 'vue'
 import { resolveApiErrorMessage } from '@/utils/api-error'
@@ -362,6 +379,15 @@ const botIdRef = computed(() => props.botId) as Ref<string>
 // ---- Data ----
 const queryCache = useQueryCache()
 
+const { data: bot } = useQuery({
+  key: () => ['bot', botIdRef.value],
+  query: async () => {
+    const { data } = await getBotsById({ path: { id: botIdRef.value }, throwOnError: true })
+    return data
+  },
+  enabled: () => !!botIdRef.value,
+})
+
 const { data: settings } = useQuery({
   key: () => ['bot-settings', botIdRef.value],
   query: async () => {
@@ -477,6 +503,31 @@ const form = reactive({
   reasoning_effort: 'medium',
 })
 
+const timezone = ref('')
+
+const timezoneModel = computed(() => timezone.value || emptyTimezoneValue)
+
+function onTimezoneChange(value: string) {
+  timezone.value = value === emptyTimezoneValue ? '' : value
+}
+
+watch(bot, (val) => {
+  if (val) {
+    timezone.value = val.timezone || ''
+  }
+}, { immediate: true })
+
+const { mutateAsync: updateBot } = useMutation({
+  mutation: async ({ id, ...body }: Record<string, unknown> & { id: string }) => {
+    const { data } = await putBotsById({ path: { id }, body, throwOnError: true })
+    return data
+  },
+  onSettled: () => {
+    queryCache.invalidateQueries({ key: ['bots'] })
+    queryCache.invalidateQueries({ key: ['bot'] })
+  },
+})
+
 const selectedMemoryProvider = computed(() =>
   memoryProviders.value.find((provider) => provider.id === form.memory_provider_id),
 )
@@ -590,10 +641,12 @@ watch(settings, (val) => {
 }, { immediate: true })
 
 const hasChanges = computed(() => {
+  const timezoneChanged = timezone.value !== (bot.value?.timezone || '')
   if (!settings.value) return true
   const s = settings.value
   let changed =
-    form.chat_model_id !== (s.chat_model_id ?? '')
+    timezoneChanged
+    || form.chat_model_id !== (s.chat_model_id ?? '')
     || form.title_model_id !== (s.title_model_id ?? '')
     || form.search_provider_id !== (s.search_provider_id ?? '')
     || form.memory_provider_id !== (s.memory_provider_id ?? '')
@@ -609,7 +662,11 @@ const hasChanges = computed(() => {
 
 async function handleSave() {
   try {
-    await updateSettings({ ...form })
+    const promises: Promise<unknown>[] = [updateSettings({ ...form })]
+    if (timezone.value !== (bot.value?.timezone || '')) {
+      promises.push(updateBot({ id: botIdRef.value, timezone: timezone.value }))
+    }
+    await Promise.all(promises)
     toast.success(t('bots.settings.saveSuccess'))
   } catch {
     return

apps/web/src/pages/bots/detail.vue

@@ -93,22 +93,6 @@
           </Badge>
           <span v-if="bot?.type">{{ botTypeLabel }}</span>
         </div>
-        <div
-          v-if="bot"
-          class="mt-1 flex items-center gap-2 text-sm text-muted-foreground"
-        >
-          <span>{{ $t('bots.timezone') }}: {{ bot.timezone || $t('bots.timezoneInherited') }}</span>
-          <Button
-            type="button"
-            variant="ghost"
-            size="sm"
-            class="h-7 px-2"
-            :disabled="botLifecyclePending"
-            @click="handleEditTimezone"
-          >
-            {{ $t('common.edit') }}
-          </Button>
-        </div>
       </div>
     </div>
     <Separator />
@@ -209,67 +193,6 @@
         </DialogFooter>
       </DialogContent>
     </Dialog>
-
-    <Dialog v-model:open="timezoneDialogOpen">
-      <DialogContent class="sm:max-w-md">
-        <DialogHeader>
-          <DialogTitle>{{ $t('bots.editTimezone') }}</DialogTitle>
-          <DialogDescription>
-            {{ $t('bots.editTimezoneDescription') }}
-          </DialogDescription>
-        </DialogHeader>
-        <div class="mt-4 flex flex-col gap-2">
-          <Select
-            :model-value="timezoneDraft || emptyTimezoneValue"
-            @update:model-value="(value) => timezoneDraft = value === emptyTimezoneValue ? '' : String(value)"
-          >
-            <SelectTrigger
-              class="w-full"
-              :disabled="timezoneSaving"
-            >
-              <SelectValue :placeholder="$t('bots.timezonePlaceholder')" />
-            </SelectTrigger>
-            <SelectContent>
-              <SelectGroup>
-                <SelectItem :value="emptyTimezoneValue">
-                  {{ $t('bots.timezoneInherited') }}
-                </SelectItem>
-                <SelectItem
-                  v-for="timezoneOption in timezones"
-                  :key="timezoneOption"
-                  :value="timezoneOption"
-                >
-                  {{ timezoneOption }}
-                </SelectItem>
-              </SelectGroup>
-            </SelectContent>
-          </Select>
-          <p class="text-sm text-muted-foreground">
-            {{ $t('bots.timezoneInheritedHint') }}
-          </p>
-        </div>
-        <DialogFooter class="mt-6">
-          <DialogClose as-child>
-            <Button
-              variant="outline"
-              :disabled="timezoneSaving"
-            >
-              {{ $t('common.cancel') }}
-            </Button>
-          </DialogClose>
-          <Button
-            :disabled="timezoneSaving || !canConfirmTimezone"
-            @click="handleConfirmTimezone"
-          >
-            <Spinner
-              v-if="timezoneSaving"
-              class="mr-1.5"
-            />
-            {{ $t('common.confirm') }}
-          </Button>
-        </DialogFooter>
-      </DialogContent>
-    </Dialog>
   </section>
 </template>
 
@@ -288,12 +211,6 @@ import {
   DialogHeader,
   DialogTitle,
   Input,
-  Select,
-  SelectContent,
-  SelectGroup,
-  SelectItem,
-  SelectTrigger,
-  SelectValue,
   Separator,
   Spinner,
   ScrollArea,
@@ -338,7 +255,6 @@ import { useAvatarInitials } from '@/composables/useAvatarInitials'
 import { useSyncedQueryParam } from '@/composables/useSyncedQueryParam'
 import { useBotStatusMeta } from '@/composables/useBotStatusMeta'
 import MasterDetailSidebarLayout from '@/components/master-detail-sidebar-layout/index.vue'
-import { emptyTimezoneValue, timezones } from '@/utils/timezones'
 type BotCheck = BotsBotCheck
 type BotContainerInfo = HandlersGetContainerResponse
 type BotContainerSnapshot = HandlersListSnapshotsResponse extends { snapshots?: (infer T)[] } ? T : never
@@ -428,12 +344,9 @@ watch(bot, (val) => {
 const activeTab = useSyncedQueryParam('tab', 'overview')
 const avatarDialogOpen = ref(false)
 const avatarUrlDraft = ref('')
-const timezoneDialogOpen = ref(false)
-const timezoneDraft = ref('')
 const avatarFallback = useAvatarInitials(() => bot.value?.display_name || botId.value || '')
 const isSavingBotName = computed(() => updateBotLoading.value)
 const avatarSaving = computed(() => updateBotLoading.value)
-const timezoneSaving = computed(() => updateBotLoading.value)
 const canConfirmAvatar = computed(() => {
   if (!bot.value) return false
   const next = avatarUrlDraft.value.trim()
@@ -446,10 +359,6 @@ const canConfirmBotName = computed(() => {
   if (!nextName) return false
   return nextName !== (bot.value.display_name || '').trim()
 })
-const canConfirmTimezone = computed(() => {
-  if (!bot.value) return false
-  return timezoneDraft.value.trim() !== (bot.value.timezone || '').trim()
-})
 const {
   hasIssue,
   isPending: botLifecyclePending,
@@ -503,12 +412,6 @@ function handleEditAvatar() {
   avatarDialogOpen.value = true
 }
 
-function handleEditTimezone() {
-  if (!bot.value || botLifecyclePending.value) return
-  timezoneDraft.value = bot.value.timezone || ''
-  timezoneDialogOpen.value = true
-}
-
 async function handleConfirmAvatar() {
   if (!bot.value || !canConfirmAvatar.value || avatarSaving.value) return
   const nextUrl = avatarUrlDraft.value.trim()
@@ -524,21 +427,6 @@ async function handleConfirmAvatar() {
   }
 }
 
-async function handleConfirmTimezone() {
-  if (!bot.value || !canConfirmTimezone.value || timezoneSaving.value) return
-  const nextTimezone = timezoneDraft.value.trim()
-  try {
-    await updateBot({
-      id: bot.value.id as string,
-      timezone: nextTimezone,
-    })
-    timezoneDialogOpen.value = false
-    toast.success(t('bots.timezoneUpdateSuccess'))
-  } catch (error) {
-    toast.error(resolveErrorMessage(error, t('bots.timezoneUpdateFailed')))
-  }
-}
-
 function handleStartEditBotName() {
   if (!bot.value) return
   isEditingBotName.value = true

apps/web/src/pages/browser-contexts/components/context-setting.vue

@@ -149,34 +149,19 @@
         </div>
 
         <FormField
-          v-slot="{ componentField }"
+          v-slot="{ value, handleChange }"
           name="timezoneId"
         >
           <FormItem>
             <Label>{{ $t('browserContext.timezoneId') }}</Label>
             <FormControl>
-              <Select
-                :model-value="componentField.modelValue || emptyTimezoneValue"
-                @update:model-value="(value) => componentField['onUpdate:modelValue'](value === emptyTimezoneValue ? '' : value)"
-              >
-                <SelectTrigger class="w-full">
-                  <SelectValue :placeholder="$t('browserContext.timezonePlaceholder')" />
-                </SelectTrigger>
-                <SelectContent>
-                  <SelectGroup>
-                    <SelectItem :value="emptyTimezoneValue">
-                      {{ $t('common.optional') }}
-                    </SelectItem>
-                    <SelectItem
-                      v-for="timezoneOption in timezones"
-                      :key="timezoneOption"
-                      :value="timezoneOption"
-                    >
-                      {{ timezoneOption }}
-                    </SelectItem>
-                  </SelectGroup>
-                </SelectContent>
-              </Select>
+              <TimezoneSelect
+                :model-value="value || emptyTimezoneValue"
+                :placeholder="$t('browserContext.timezonePlaceholder')"
+                allow-empty
+                :empty-label="$t('common.optional')"
+                @update:model-value="(val) => handleChange(val === emptyTimezoneValue ? '' : val)"
+              />
             </FormControl>
           </FormItem>
         </FormField>
@@ -249,12 +234,6 @@ import {
   Label,
   Separator,
   Button,
-  Select,
-  SelectContent,
-  SelectGroup,
-  SelectItem,
-  SelectTrigger,
-  SelectValue,
   Switch,
 } from '@memohai/ui'
 import { toTypedSchema } from '@vee-validate/zod'
@@ -270,7 +249,8 @@ import { toast } from 'vue-sonner'
 import { useDialogMutation } from '@/composables/useDialogMutation'
 import ConfirmPopover from '@/components/confirm-popover/index.vue'
 import { resolveApiErrorMessage } from '@/utils/api-error'
-import { emptyTimezoneValue, timezones } from '@/utils/timezones'
+import { emptyTimezoneValue } from '@/utils/timezones'
+import TimezoneSelect from '@/components/timezone-select/index.vue'
 
 const { t } = useI18n()
 const { run } = useDialogMutation()

apps/web/src/pages/settings/components/profile-section.vue

@@ -48,29 +48,11 @@
       </div>
       <div class="space-y-2">
         <Label for="settings-timezone">{{ $t('settings.timezone') }}</Label>
-        <Select
+        <TimezoneSelect
           :model-value="timezone"
+          :placeholder="$t('settings.timezonePlaceholder')"
           @update:model-value="onTimezoneChange"
-        >
-          <SelectTrigger
-            id="settings-timezone"
-            class="w-full"
-            :aria-label="$t('settings.timezone')"
-          >
-            <SelectValue :placeholder="$t('settings.timezonePlaceholder')" />
-          </SelectTrigger>
-          <SelectContent>
-            <SelectGroup>
-              <SelectItem
-                v-for="timezoneOption in timezones"
-                :key="timezoneOption"
-                :value="timezoneOption"
-              >
-                {{ timezoneOption }}
-              </SelectItem>
-            </SelectGroup>
-          </SelectContent>
-        </Select>
+        />
       </div>
       <div class="flex justify-end">
         <Button
@@ -90,16 +72,10 @@ import {
   Button,
   Input,
   Label,
-  Select,
-  SelectContent,
-  SelectGroup,
-  SelectItem,
-  SelectTrigger,
-  SelectValue,
   Separator,
   Spinner,
 } from '@memohai/ui'
-import { timezones } from '@/utils/timezones'
+import TimezoneSelect from '@/components/timezone-select/index.vue'
 
 defineProps<{
   displayUserId: string

apps/web/src/utils/timezones.ts

@@ -5,3 +5,17 @@ export const timezones = typeof Intl.supportedValuesOf === 'function'
   : fallbackTimezones
 
 export const emptyTimezoneValue = '__empty_timezone__'
+
+export function getUtcOffsetLabel(tz: string): string {
+  try {
+    const now = new Date()
+    const parts = new Intl.DateTimeFormat('en-US', {
+      timeZone: tz,
+      timeZoneName: 'shortOffset',
+    }).formatToParts(now)
+    const offsetPart = parts.find(p => p.type === 'timeZoneName')
+    return offsetPart?.value ?? ''
+  } catch {
+    return ''
+  }
+}

internal/agent/agent.go

@@ -405,6 +405,7 @@ func (a *Agent) assembleTools(ctx context.Context, cfg RunConfig) ([]sdk.Tool, e
 		SupportsImageInput: cfg.SupportsImageInput,
 		IsSubagent:         cfg.Identity.IsSubagent,
 		Skills:             skillsMap,
+		TimezoneLocation:   cfg.Identity.TimezoneLocation,
 	}
 
 	var allTools []sdk.Tool

internal/agent/tools/contacts.go

@@ -67,7 +67,7 @@ func (p *ContactsProvider) Tools(_ context.Context, session SessionContext) ([]s
 						"conversation_type": r.ConversationType,
 						"target":            r.ReplyTarget,
 						"conversation_id":   r.ConversationID,
-						"last_active":       r.UpdatedAt.Format("2006-01-02T15:04:05Z"),
+						"last_active":       sess.FormatTime(r.UpdatedAt),
 					}
 					if len(r.Metadata) > 0 {
 						if v, ok := r.Metadata["conversation_name"].(string); ok && v != "" {

internal/agent/tools/history.go

@@ -166,8 +166,8 @@ func (p *HistoryProvider) execListSessions(ctx context.Context, sess SessionCont
 			"platform":          s.ChannelType,
 			"route_id":          s.RouteID,
 			"conversation_type": s.RouteConversationType,
-			"last_active":       s.UpdatedAt.Format(time.RFC3339),
-			"created_at":        s.CreatedAt.Format(time.RFC3339),
+			"last_active":       sess.FormatTime(s.UpdatedAt),
+			"created_at":        sess.FormatTime(s.CreatedAt),
 		}
 
 		if m := s.RouteMetadata; len(m) > 0 {
@@ -261,7 +261,7 @@ func (p *HistoryProvider) execSearchMessages(ctx context.Context, sess SessionCo
 			"session_id": row.SessionID.String(),
 			"role":       row.Role,
 			"text":       text,
-			"created_at": row.CreatedAt.Time.Format(time.RFC3339),
+			"created_at": sess.FormatTime(row.CreatedAt.Time),
 		}
 		if dbpkg.TextToString(row.Platform) != "" {
 			entry["platform"] = dbpkg.TextToString(row.Platform)

internal/agent/tools/types.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math"
 	"strings"
+	"time"
 
 	sdk "github.com/memohai/twilight-ai/sdk"
 )
@@ -28,6 +29,15 @@ type SessionContext struct {
 	SupportsImageInput bool
 	IsSubagent         bool
 	Skills             map[string]SkillDetail
+	TimezoneLocation   *time.Location
+}
+
+// FormatTime formats a time.Time using the session timezone (falls back to UTC).
+func (s SessionContext) FormatTime(t time.Time) string {
+	if s.TimezoneLocation != nil {
+		t = t.In(s.TimezoneLocation)
+	}
+	return t.Format(time.RFC3339)
 }
 
 // ToolProvider supplies a set of tools for the agent.

internal/conversation/flow/resolver.go

@@ -158,7 +158,7 @@ func (r *Resolver) resolve(ctx context.Context, req conversation.ChatRequest) (r
 		return resolvedContext{}, err
 	}
 	loopDetectionEnabled := r.loadBotLoopDetectionEnabled(ctx, req.BotID)
-	userTimezoneName, userClockLocation := r.resolveUserTimezone(ctx, req.UserID)
+	userTimezoneName, userClockLocation := r.resolveTimezone(ctx, req.BotID, req.UserID)
 
 	var chatSettings conversation.Settings
 	if r.conversationSvc != nil {

internal/conversation/flow/resolver_memory.go

@@ -69,12 +69,14 @@ func (r *Resolver) storeMemory(ctx context.Context, req conversation.ChatRequest
 	if p == nil {
 		return
 	}
+	_, tzLoc := r.resolveTimezone(ctx, req.BotID, req.UserID)
 	if err := p.OnAfterChat(ctx, memprovider.AfterChatRequest{
 		BotID:             botID,
 		Messages:          memMsgs,
 		UserID:            strings.TrimSpace(req.UserID),
 		ChannelIdentityID: strings.TrimSpace(req.SourceChannelIdentityID),
 		DisplayName:       r.resolveDisplayName(ctx, req),
+		TimezoneLocation:  tzLoc,
 	}); err != nil {
 		r.logger.Warn("memory provider OnAfterChat failed", slog.String("bot_id", botID), slog.Any("error", err))
 	}

internal/conversation/flow/resolver_timezone.go

@@ -6,39 +6,90 @@ import (
 	"strings"
 	"time"
 
+	"github.com/memohai/memoh/internal/db"
 	"github.com/memohai/memoh/internal/timezone"
 )
 
-func (r *Resolver) resolveUserTimezone(ctx context.Context, userID string) (string, *time.Location) {
-	fallbackLocation := r.clockLocation
-	fallbackName := timezone.DefaultName
-	if fallbackLocation != nil {
-		fallbackName = fallbackLocation.String()
-	} else {
-		fallbackLocation = timezone.MustResolve(fallbackName)
+// resolveTimezone resolves the effective timezone for a request.
+// Priority: bot timezone > user timezone > system default.
+func (r *Resolver) resolveTimezone(ctx context.Context, botID, userID string) (string, *time.Location) {
+	fallbackName, fallbackLocation := r.systemTimezoneDefaults()
+
+	// 1. Try bot timezone first.
+	if name, loc, ok := r.loadBotTimezone(ctx, botID); ok {
+		return name, loc
 	}
 
-	if r.accountService == nil {
-		return fallbackName, fallbackLocation
+	// 2. Fall back to user timezone.
+	if name, loc, ok := r.loadUserTimezone(ctx, userID); ok {
+		return name, loc
 	}
-	account, err := r.accountService.Get(ctx, strings.TrimSpace(userID))
+
+	return fallbackName, fallbackLocation
+}
+
+func (r *Resolver) systemTimezoneDefaults() (string, *time.Location) {
+	if r.clockLocation != nil {
+		return r.clockLocation.String(), r.clockLocation
+	}
+	return timezone.DefaultName, timezone.MustResolve(timezone.DefaultName)
+}
+
+func (r *Resolver) loadBotTimezone(ctx context.Context, botID string) (string, *time.Location, bool) {
+	if r.queries == nil || strings.TrimSpace(botID) == "" {
+		return "", nil, false
+	}
+	botUUID, err := db.ParseUUID(botID)
 	if err != nil {
-		return fallbackName, fallbackLocation
+		return "", nil, false
 	}
-	if strings.TrimSpace(account.Timezone) == "" {
-		return fallbackName, fallbackLocation
+	row, err := r.queries.GetBotByID(ctx, botUUID)
+	if err != nil {
+		return "", nil, false
 	}
-	loc, name, err := timezone.Resolve(account.Timezone)
+	tz := ""
+	if row.Timezone.Valid {
+		tz = strings.TrimSpace(row.Timezone.String)
+	}
+	if tz == "" {
+		return "", nil, false
+	}
+	loc, name, err := timezone.Resolve(tz)
 	if err != nil {
 		if r.logger != nil {
-			r.logger.Warn(
-				"resolve user timezone failed",
-				slog.String("user_id", userID),
-				slog.String("timezone", account.Timezone),
+			r.logger.Warn("resolve bot timezone failed",
+				slog.String("bot_id", botID),
+				slog.String("timezone", tz),
 				slog.Any("error", err),
 			)
 		}
-		return fallbackName, fallbackLocation
+		return "", nil, false
 	}
-	return name, loc
+	return name, loc, true
+}
+
+func (r *Resolver) loadUserTimezone(ctx context.Context, userID string) (string, *time.Location, bool) {
+	if r.accountService == nil || strings.TrimSpace(userID) == "" {
+		return "", nil, false
+	}
+	account, err := r.accountService.Get(ctx, strings.TrimSpace(userID))
+	if err != nil {
+		return "", nil, false
+	}
+	tz := strings.TrimSpace(account.Timezone)
+	if tz == "" {
+		return "", nil, false
+	}
+	loc, name, err := timezone.Resolve(tz)
+	if err != nil {
+		if r.logger != nil {
+			r.logger.Warn("resolve user timezone failed",
+				slog.String("user_id", userID),
+				slog.String("timezone", tz),
+				slog.Any("error", err),
+			)
+		}
+		return "", nil, false
+	}
+	return name, loc, true
 }

internal/memory/adapters/builtin/formation.go

@@ -39,7 +39,8 @@ func runFormation(ctx context.Context, logger *slog.Logger, llm adapters.LLM, ru
 	result := formationResult{}
 
 	extracted, err := llm.Extract(ctx, adapters.ExtractRequest{
-		Messages: req.Messages,
+		Messages:         req.Messages,
+		TimezoneLocation: req.TimezoneLocation,
 	})
 	if err != nil {
 		logger.Warn("memory formation: extract failed", slog.String("bot_id", botID), slog.Any("error", err))

internal/memory/adapters/types.go

@@ -24,6 +24,7 @@ type AfterChatRequest struct {
 	UserID            string
 	ChannelIdentityID string
 	DisplayName       string
+	TimezoneLocation  *time.Location
 }
 
 // LLM is the interface for LLM operations needed by memory service.
@@ -148,9 +149,10 @@ type DeleteResponse struct {
 }
 
 type ExtractRequest struct {
-	Messages []Message      `json:"messages"`
-	Filters  map[string]any `json:"filters,omitempty"`
-	Metadata map[string]any `json:"metadata,omitempty"`
+	Messages         []Message      `json:"messages"`
+	Filters          map[string]any `json:"filters,omitempty"`
+	Metadata         map[string]any `json:"metadata,omitempty"`
+	TimezoneLocation *time.Location `json:"-"`
 }
 
 type ExtractResponse struct {

internal/memory/memllm/client.go

@@ -79,7 +79,11 @@ func (c *Client) Extract(ctx context.Context, req adapters.ExtractRequest) (adap
 		return adapters.ExtractResponse{}, nil
 	}
 
-	systemPrompt := strings.ReplaceAll(agent.MemoryExtractPrompt, "{{today}}", time.Now().UTC().Format("2006-01-02"))
+	now := time.Now()
+	if req.TimezoneLocation != nil {
+		now = now.In(req.TimezoneLocation)
+	}
+	systemPrompt := strings.ReplaceAll(agent.MemoryExtractPrompt, "{{today}}", now.Format("2006-01-02"))
 
 	result, err := sdk.GenerateTextResult(ctx,
 		sdk.WithModel(c.model()),