diff --git a/apps/client-chrome/src/App.tsx b/apps/client-chrome/src/App.tsx
index d335f55..2c8e045 100644
--- a/apps/client-chrome/src/App.tsx
+++ b/apps/client-chrome/src/App.tsx
@@ -1,14 +1,14 @@
 import { ArrowLeft, CalendarDays, Check, Cloud, Copy, Link2, Monitor, RefreshCw, Search, Send, Settings, Sparkles, Trash2 } from 'lucide-react'
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
 import { getActiveTab, subscribeToActiveTab } from './chromeApi'
-import { getBrowserTimeZone, getLocalDate, normalizeBrainEndpointUrl, runDailySummary } from './brainCapture'
-import type { DailySummaryResult } from './brainCapture'
+import { getBrowserTimeZone, getDailySummaryVariant, getLocalDate, normalizeBrainEndpointUrl, runDailySummary } from './brainCapture'
+import type { DailySummaryResult, DailySummarySource, EvidenceSupport, SummaryLevel } from './brainCapture'
 import { DEFAULT_BRAIN_SERVER_URL } from './config'
 import { checkContextServerConnection, createUrlMemoryCapture, deleteRemoteCapture, listRemoteCaptures, normalizeEndpointUrl, postCapture } from './contextCapture'
 import type { RemoteCapture } from './contextCapture'
 import { filterLinkedThoughtsForUrl, LinkedThoughtsLoader } from './linkedThoughts'
 import { createI18n, resolveLocale } from './i18n'
-import type { LocalePreference } from './i18n'
+import type { LocalePreference, MessageKey } from './i18n'
 import { loadLocalePreference, loadStoredSettings, saveAppData, saveLocalePreference, saveStoredSettings, subscribeToLocalePreferenceChanges, subscribeToStoredSettingsChanges } from './storage'
 import { copyTextToClipboard, filterThoughtsForCopy, formatThoughtsForClipboard, getThoughtCopyRange } from './thoughtExport'
 import type { AppData, CaptureOutboxItem, ChromeSurface, DeploymentMode, SavedTab, UrlMemory } from './types'
@@ -29,6 +29,87 @@ export function canCaptureOnUrl(url: string | undefined) {
   }
 }
 
+const SUMMARY_LEVELS: SummaryLevel[] = ['quick', 'standard', 'deep']
+const SUMMARY_LEVEL_KEYS: Record<SummaryLevel, MessageKey> = {
+  quick: 'summary.level.quick',
+  standard: 'summary.level.standard',
+  deep: 'summary.level.deep',
+}
+const SUPPORT_KEYS: Record<EvidenceSupport, MessageKey> = {
+  direct: 'summary.support.direct',
+  partial: 'summary.support.partial',
+  unverified: 'summary.support.unverified',
+  conflict: 'summary.support.conflict',
+}
+
+type SummaryResultViewProps = {
+  result: DailySummaryResult
+  level: SummaryLevel
+  onLevelChange: (level: SummaryLevel) => void
+  onOpenSource: (source: DailySummarySource) => void
+  formatDate: ReturnType<typeof createI18n>['formatDate']
+  t: ReturnType<typeof createI18n>['t']
+}
+
+function SummaryResultView({ result, level, onLevelChange, onOpenSource, formatDate, t }: SummaryResultViewProps) {
+  const sources = result.sources ?? []
+  const sourcesById = new Map(sources.map((source) => [source.recordId, source]))
+
+  return (
+    <section className={`summary-result ${result.recordCount === 0 ? 'is-empty' : ''}`} aria-live="polite">
+      <div className="summary-result-meta"><span>{result.recordCount === 0 ? t('summary.noRecords') : t('summary.recordCount', { count: result.recordCount })}</span><span>{result.date} · {result.timezone}</span></div>
+      {result.variants ? (
+        <div className="summary-levels" role="tablist" aria-label={t('summary.levelLabel')}>
+          {SUMMARY_LEVELS.map((option) => (
+            <button
+              className={level === option ? 'is-selected' : ''}
+              key={option}
+              type="button"
+              role="tab"
+              aria-selected={level === option}
+              onClick={() => onLevelChange(option)}
+            >
+              {t(SUMMARY_LEVEL_KEYS[option])}
+            </button>
+          ))}
+        </div>
+      ) : null}
+      <p className="summary-text">{getDailySummaryVariant(result, level)}</p>
+      {result.keyPoints.length > 0 ? <div className="summary-points"><h2>{t('summary.keyPoints')}</h2><ul>{result.keyPoints.map((point) => <li key={point}>{point}</li>)}</ul></div> : <p className="summary-empty-help">{t('summary.emptyHelp')}</p>}
+      {result.claims && result.claims.length > 0 ? (
+        <div className="summary-evidence">
+          <div className="summary-evidence-heading"><h2>{t('summary.evidenceTitle')}</h2><span>{t('summary.evidenceHelp')}</span></div>
+          <div className="summary-claims">
+            {result.claims.map((claim) => (
+              <article className={`summary-claim support-${claim.support}`} key={claim.id}>
+                <div className="summary-claim-status">{t(SUPPORT_KEYS[claim.support])}</div>
+                <p>{claim.text}</p>
+                {claim.sourceIds.length > 0 ? <div className="summary-claim-sources">{claim.sourceIds.map((sourceId) => {
+                  const source = sourcesById.get(sourceId)
+                  return source ? <button className="summary-source-chip" key={sourceId} type="button" title={source.preview} onClick={() => onOpenSource(source)}>{source.title || source.preview}</button> : null
+                })}</div> : null}
+              </article>
+            ))}
+          </div>
+        </div>
+      ) : null}
+      {sources.length > 0 ? (
+        <div className="summary-sources">
+          <h2>{t('summary.sourcesTitle', { count: sources.length })}</h2>
+          <div className="summary-source-list">
+            {sources.map((source) => (
+              <button className="summary-source" key={source.recordId} type="button" title={source.preview} onClick={() => onOpenSource(source)}>
+                <strong>{source.title || source.client} · {formatDate(new Date(source.recordedAt), { dateStyle: 'medium', timeStyle: 'short' })}</strong>
+                <span>{source.preview}</span>
+              </button>
+            ))}
+          </div>
+        </div>
+      ) : null}
+    </section>
+  )
+}
+
 export function App({ surface }: { surface: ChromeSurface }) {
   const [localePreference, setLocalePreference] = useState<LocalePreference>('auto')
   const locale = resolveLocale(localePreference)
@@ -51,6 +132,7 @@ export function App({ surface }: { surface: ChromeSurface }) {
   const [connectionChecking, setConnectionChecking] = useState(false)
   const [thoughts, setThoughts] = useState<RemoteCapture[]>([])
   const [thoughtQuery, setThoughtQuery] = useState('')
+  const [thoughtIdFilter, setThoughtIdFilter] = useState('')
   const [thoughtUrlFilter, setThoughtUrlFilter] = useState('')
   const [thoughtStatus, setThoughtStatus] = useState('')
   const [copyStart, setCopyStart] = useState('')
@@ -59,6 +141,7 @@ export function App({ surface }: { surface: ChromeSurface }) {
   const [linkedThoughts, setLinkedThoughts] = useState<RemoteCapture[]>([])
   const [summaryDate, setSummaryDate] = useState(() => getLocalDate())
   const [summaryResult, setSummaryResult] = useState<DailySummaryResult | null>(null)
+  const [summaryLevel, setSummaryLevel] = useState<SummaryLevel>('standard')
   const [summaryStatus, setSummaryStatus] = useState('')
   const [summaryLoading, setSummaryLoading] = useState(false)
   const [settingsChangedElsewhere, setSettingsChangedElsewhere] = useState(false)
@@ -485,13 +568,32 @@ export function App({ surface }: { surface: ChromeSurface }) {
   }, [activeTab?.url, linkedThoughtsLoader, loadLinkedThoughts, t])
 
   const openThoughts = () => {
+    setThoughtIdFilter('')
     setThoughtUrlFilter('')
+    setThoughtQuery('')
     setScreen('thoughts')
     void loadThoughts()
   }
 
+  const openSourceRecord = (source: DailySummarySource) => {
+    if (data?.sync.endpointUrl && apiToken) {
+      setThoughtIdFilter(source.recordId)
+      setThoughtQuery('')
+      setThoughtUrlFilter('')
+      setScreen('thoughts')
+      void loadThoughts()
+      return
+    }
+    if (source.url) {
+      void openThoughtLink(source.url)
+      return
+    }
+    setSummaryStatus(t('summary.sourceConnectionRequired'))
+  }
+
   const openSummary = () => {
     setSummaryDate(getLocalDate())
+    setSummaryLevel('standard')
     setSummaryStatus('')
     setScreen('summary')
   }
@@ -514,8 +616,9 @@ export function App({ surface }: { surface: ChromeSurface }) {
     }
   }
 
-  const openLinkedThoughts = () => {
+const openLinkedThoughts = () => {
     if (!activeTab?.url) return
+    setThoughtIdFilter('')
     setThoughtQuery('')
     setThoughtUrlFilter(activeTab.url)
     setScreen('thoughts')
@@ -602,6 +705,7 @@ export function App({ surface }: { surface: ChromeSurface }) {
   const canCapture = !activeTab || canCaptureOnUrl(activeTab.url)
   const visibleThoughts = thoughts.filter((thought) =>
     thought.data.content.toLocaleLowerCase().includes(thoughtQuery.trim().toLocaleLowerCase()) &&
+    (!thoughtIdFilter || thought.id === thoughtIdFilter) &&
     (!thoughtUrlFilter || thought.data.context?.browser?.url === thoughtUrlFilter)
   )
 
@@ -725,11 +829,14 @@ export function App({ surface }: { surface: ChromeSurface }) {
           </button>
           {summaryStatus ? <p className="summary-error" role="alert">{summaryStatus}</p> : null}
           {summaryResult ? (
-            <section className={`summary-result ${summaryResult.recordCount === 0 ? 'is-empty' : ''}`} aria-live="polite">
-              <div className="summary-result-meta"><span>{summaryResult.recordCount === 0 ? t('summary.noRecords') : t('summary.recordCount', { count: summaryResult.recordCount })}</span><span>{summaryResult.date} · {summaryResult.timezone}</span></div>
-              <p className="summary-text">{summaryResult.summary}</p>
-              {summaryResult.keyPoints.length > 0 ? <div className="summary-points"><h2>{t('summary.keyPoints')}</h2><ul>{summaryResult.keyPoints.map((point) => <li key={point}>{point}</li>)}</ul></div> : <p className="summary-empty-help">{t('summary.emptyHelp')}</p>}
-            </section>
+            <SummaryResultView
+              result={summaryResult}
+              level={summaryLevel}
+              onLevelChange={setSummaryLevel}
+              onOpenSource={openSourceRecord}
+              formatDate={formatDate}
+              t={t}
+            />
           ) : null}
         </section>
       ) : screen === 'thoughts' ? (
@@ -744,6 +851,7 @@ export function App({ surface }: { surface: ChromeSurface }) {
             <div><Search size={17} aria-hidden="true" /><input value={thoughtQuery} onChange={(event) => setThoughtQuery(event.target.value)} placeholder={t('thoughts.searchPlaceholder')} /></div>
           </label>
           {thoughtUrlFilter ? <div className="link-filter"><Link2 size={14} /><span>{t('thoughts.filteredByLink')}</span><button type="button" onClick={() => setThoughtUrlFilter('')}>{t('thoughts.showAll')}</button></div> : null}
+          {thoughtIdFilter ? <div className="link-filter"><Link2 size={14} /><span>{t('thoughts.filteredByRecord')}</span><button type="button" onClick={() => setThoughtIdFilter('')}>{t('thoughts.showAll')}</button></div> : null}
           <section className="copy-thoughts" aria-labelledby="copy-thoughts-title">
             <div className="copy-thoughts-heading"><div><p className="eyebrow">{t('thoughts.externalUse')}</p><h2 id="copy-thoughts-title">{t('thoughts.copyTitle')}</h2></div><Copy size={18} aria-hidden="true" /></div>
             <p>{t('thoughts.copyDescription')}</p>
diff --git a/apps/client-chrome/src/brainCapture.ts b/apps/client-chrome/src/brainCapture.ts
index 1248167..ebc608a 100644
--- a/apps/client-chrome/src/brainCapture.ts
+++ b/apps/client-chrome/src/brainCapture.ts
@@ -8,12 +8,33 @@ export type DailySummaryInput = {
   timezone: string
 }
 
+export type SummaryLevel = 'quick' | 'standard' | 'deep'
+export type EvidenceSupport = 'direct' | 'partial' | 'unverified' | 'conflict'
+export type DailySummaryVariants = Record<SummaryLevel, string>
+export type DailySummaryClaim = {
+  id: string
+  text: string
+  sourceIds: string[]
+  support: EvidenceSupport
+}
+export type DailySummarySource = {
+  recordId: string
+  preview: string
+  recordedAt: string
+  client: string
+  title?: string
+  url?: string
+}
+
 export type DailySummaryResult = {
   date: string
   timezone: string
   recordCount: number
   summary: string
   keyPoints: string[]
+  variants?: DailySummaryVariants
+  claims?: DailySummaryClaim[]
+  sources?: DailySummarySource[]
 }
 
 export class BrainRequestError extends Error {}
@@ -38,12 +59,45 @@ function headers(apiToken: string) {
 function isDailySummaryResult(value: unknown): value is DailySummaryResult {
   if (!value || typeof value !== 'object') return false
   const result = value as Partial<DailySummaryResult>
-  return typeof result.date === 'string' &&
+  if (!(typeof result.date === 'string' &&
     typeof result.timezone === 'string' &&
     typeof result.recordCount === 'number' &&
     typeof result.summary === 'string' &&
     Array.isArray(result.keyPoints) &&
-    result.keyPoints.every((point) => typeof point === 'string')
+    result.keyPoints.every((point) => typeof point === 'string'))) return false
+
+  if (result.variants !== undefined) {
+    const variants = result.variants
+    if (!variants || typeof variants !== 'object' || Array.isArray(variants)) return false
+    if (!['quick', 'standard', 'deep'].every((level) => typeof variants[level as SummaryLevel] === 'string')) return false
+  }
+
+  if (result.claims !== undefined) {
+    if (!Array.isArray(result.claims) || !result.claims.every((claim) => {
+      if (!claim || typeof claim !== 'object') return false
+      const item = claim as Partial<DailySummaryClaim>
+      return typeof item.id === 'string' && typeof item.text === 'string' && Array.isArray(item.sourceIds) &&
+        item.sourceIds.every((sourceId) => typeof sourceId === 'string') &&
+        typeof item.support === 'string' && ['direct', 'partial', 'unverified', 'conflict'].includes(item.support)
+    })) return false
+  }
+
+  if (result.sources !== undefined) {
+    if (!Array.isArray(result.sources) || !result.sources.every((source) => {
+      if (!source || typeof source !== 'object') return false
+      const item = source as Partial<DailySummarySource>
+      return typeof item.recordId === 'string' && typeof item.preview === 'string' &&
+        typeof item.recordedAt === 'string' && typeof item.client === 'string' &&
+        (item.title === undefined || typeof item.title === 'string') &&
+        (item.url === undefined || typeof item.url === 'string')
+    })) return false
+  }
+
+  return true
+}
+
+export function getDailySummaryVariant(result: DailySummaryResult, level: SummaryLevel): string {
+  return result.variants?.[level] ?? result.summary
 }
 
 function errorMessage(status: number, body: unknown) {
diff --git a/apps/client-chrome/src/i18n.ts b/apps/client-chrome/src/i18n.ts
index e350ba8..8dc97d1 100644
--- a/apps/client-chrome/src/i18n.ts
+++ b/apps/client-chrome/src/i18n.ts
@@ -129,11 +129,24 @@ const messages = {
     'summary.recordCount': 'Context 기록 {count}개',
     'summary.keyPoints': '핵심 포인트',
     'summary.emptyHelp': '먼저 생각을 남기면 이 날짜의 요약이 여기에 나타납니다.',
+    'summary.levelLabel': '답변 깊이',
+    'summary.level.quick': '빠른 답변',
+    'summary.level.standard': '일반 답변',
+    'summary.level.deep': '자세한 답변',
+    'summary.evidenceTitle': '주장과 근거',
+    'summary.evidenceHelp': '근거 상태를 쉽게 확인할 수 있습니다.',
+    'summary.support.direct': '직접 확인됨',
+    'summary.support.partial': '부분 확인',
+    'summary.support.unverified': '미확인',
+    'summary.support.conflict': '충돌 있음',
+    'summary.sourcesTitle': '근거 기록 {count}개',
+    'summary.sourceConnectionRequired': '원문 기록을 열려면 Context Server 연결이 필요합니다.',
     'thoughts.title': '생각 전체 조회',
     'thoughts.refresh': '생각 새로고침',
     'thoughts.search': '생각 검색',
     'thoughts.searchPlaceholder': '기억나는 단어를 입력하세요',
     'thoughts.filteredByLink': '현재 링크의 기록만 표시 중',
+    'thoughts.filteredByRecord': '선택한 기록만 표시 중',
     'thoughts.showAll': '전체 보기',
     'thoughts.externalUse': 'External use',
     'thoughts.copyTitle': '생각 복사',
@@ -287,11 +300,24 @@ const messages = {
     'summary.recordCount': '{count} Context record(s)',
     'summary.keyPoints': 'Key points',
     'summary.emptyHelp': 'Leave a thought first and its summary for this date will appear here.',
+    'summary.levelLabel': 'Answer depth',
+    'summary.level.quick': 'Quick',
+    'summary.level.standard': 'Standard',
+    'summary.level.deep': 'Deep',
+    'summary.evidenceTitle': 'Claims and evidence',
+    'summary.evidenceHelp': 'See how each claim is supported.',
+    'summary.support.direct': 'Directly supported',
+    'summary.support.partial': 'Partially supported',
+    'summary.support.unverified': 'Unverified',
+    'summary.support.conflict': 'Conflicting sources',
+    'summary.sourcesTitle': '{count} source record(s)',
+    'summary.sourceConnectionRequired': 'Connect Context Server to open the original record.',
     'thoughts.title': 'All thoughts',
     'thoughts.refresh': 'Refresh thoughts',
     'thoughts.search': 'Search thoughts',
     'thoughts.searchPlaceholder': 'Enter a word you remember',
     'thoughts.filteredByLink': 'Showing only records for the current link',
+    'thoughts.filteredByRecord': 'Showing the selected record only',
     'thoughts.showAll': 'Show all',
     'thoughts.externalUse': 'External use',
     'thoughts.copyTitle': 'Copy thoughts',
diff --git a/apps/client-chrome/src/styles.css b/apps/client-chrome/src/styles.css
index fc694b9..ec6c63f 100644
--- a/apps/client-chrome/src/styles.css
+++ b/apps/client-chrome/src/styles.css
@@ -77,12 +77,37 @@ button { cursor: pointer; }
 .summary-result.is-empty { border-color: #4c5664; background: #272a2e; }
 .summary-result-meta { display: flex; justify-content: space-between; gap: 12px; color: #9fc4ff; font-size: 12px; font-weight: 700; }
 .summary-result-meta span:last-child { color: #9b9d9f; font-weight: 500; text-align: right; }
+.summary-levels { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 6px; margin-top: 14px; padding: 4px; border: 1px solid #465469; border-radius: 10px; background: #20252c; }
+.summary-levels button { min-height: 32px; border: 0; border-radius: 7px; background: transparent; color: #aeb7c4; font-size: 12px; font-weight: 700; }
+.summary-levels button:hover, .summary-levels button.is-selected { background: #354256; color: #edf4ff; }
 .summary-text { margin: 16px 0 0; color: #f0f2f5; font-size: 17px; line-height: 1.55; white-space: pre-wrap; }
 .summary-points { margin-top: 18px; padding-top: 15px; border-top: 1px solid #424b58; }
 .summary-points h2 { margin: 0; color: #dce6f8; font-size: 13px; }
 .summary-points ul { display: grid; gap: 9px; margin: 11px 0 0; padding-left: 20px; color: #d6dbe3; font-size: 13px; line-height: 1.5; }
 .summary-points li::marker { color: #9fc4ff; }
 .summary-empty-help { margin: 14px 0 0; color: #aeb2b5; font-size: 12px; line-height: 1.5; }
+.summary-evidence, .summary-sources { margin-top: 18px; padding-top: 15px; border-top: 1px solid #424b58; }
+.summary-evidence-heading { display: grid; gap: 4px; }
+.summary-evidence-heading h2, .summary-sources h2 { margin: 0; color: #dce6f8; font-size: 13px; }
+.summary-evidence-heading span { color: #9b9d9f; font-size: 11px; line-height: 1.45; }
+.summary-claims { display: grid; gap: 9px; margin-top: 11px; }
+.summary-claim { padding: 11px 12px; border: 1px solid #4b5665; border-radius: 9px; background: #20252c; }
+.summary-claim.support-direct { border-color: #496d62; }
+.summary-claim.support-partial { border-color: #75643d; }
+.summary-claim.support-unverified, .summary-claim.support-conflict { border-color: #765050; }
+.summary-claim-status { color: #b8d4ff; font-size: 11px; font-weight: 750; }
+.support-partial .summary-claim-status { color: #ecd18a; }
+.support-unverified .summary-claim-status, .support-conflict .summary-claim-status { color: #f0b5b5; }
+.summary-claim p { margin: 6px 0 0; color: #e7e9ec; font-size: 13px; line-height: 1.45; }
+.summary-claim-sources { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 9px; }
+.summary-source-chip { max-width: 100%; overflow: hidden; padding: 5px 8px; border: 1px solid #536278; border-radius: 7px; background: #2b3544; color: #cfe0f7; font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }
+.summary-source-chip:hover { border-color: #9fc4ff; }
+.summary-source-list { display: grid; gap: 7px; margin-top: 10px; }
+.summary-source { display: grid; gap: 4px; width: 100%; min-width: 0; padding: 9px 10px; border: 1px solid #465469; border-radius: 8px; background: #20252c; color: #c8d5e6; text-align: left; }
+.summary-source:hover { border-color: #9fc4ff; background: #293241; }
+.summary-source strong { overflow: hidden; color: #cfe0f7; font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }
+.summary-source span { display: -webkit-box; overflow: hidden; color: #d6dbe3; font-size: 12px; line-height: 1.4; -webkit-box-orient: vertical; -webkit-line-clamp: 2; }
+.summary-source:focus-visible, .summary-source-chip:focus-visible, .summary-levels button:focus-visible { outline: 2px solid #fff; outline-offset: 2px; }
 .spin { animation: summary-spin 1s linear infinite; }
 @keyframes summary-spin { to { transform: rotate(360deg); } }
 .search-field > div { position: relative; }
diff --git a/apps/client-chrome/test/brainCapture.test.ts b/apps/client-chrome/test/brainCapture.test.ts
index 85898cd..08e1ad7 100644
--- a/apps/client-chrome/test/brainCapture.test.ts
+++ b/apps/client-chrome/test/brainCapture.test.ts
@@ -1,5 +1,5 @@
 import { describe, expect, it, vi } from 'vitest'
-import { getLocalDate, runDailySummary } from '../src/brainCapture'
+import { getDailySummaryVariant, getLocalDate, runDailySummary } from '../src/brainCapture'
 
 describe('runDailySummary', () => {
   it('sends the daily-summary action and returns the structured result', async () => {
@@ -45,6 +45,27 @@ describe('runDailySummary', () => {
     }, fetchImpl)).resolves.toMatchObject({ recordCount: 0 })
   })
 
+  it('accepts evidence-linked variants and falls back for legacy responses', async () => {
+    const fetchImpl = vi.fn(async () => new Response(JSON.stringify({ result: {
+      date: '2026-08-13',
+      timezone: 'Asia/Seoul',
+      recordCount: 1,
+      summary: '기본 요약',
+      keyPoints: ['핵심'],
+      variants: { quick: '짧게', standard: '일반적으로', deep: '자세히' },
+      claims: [{ id: 'claim-1', text: '주장', sourceIds: ['record-1'], support: 'direct' }],
+      sources: [{ recordId: 'record-1', preview: '원문 기록', recordedAt: '2026-08-13T00:00:00.000Z', client: 'chrome' }]
+    } })))
+
+    const result = await runDailySummary({ endpointUrl: 'http://brain.test', apiToken: '' }, {
+      date: '2026-08-13', timezone: 'Asia/Seoul'
+    }, fetchImpl)
+
+    expect(result.sources?.[0].recordId).toBe('record-1')
+    expect(getDailySummaryVariant(result, 'quick')).toBe('짧게')
+    expect(getDailySummaryVariant({ ...result, variants: undefined }, 'deep')).toBe('기본 요약')
+  })
+
   it('maps server errors into a user-facing request error', async () => {
     const fetchImpl = vi.fn(async () => new Response(JSON.stringify({ error: 'context unavailable' }), { status: 502 }))
     await expect(runDailySummary({ endpointUrl: 'http://brain.test', apiToken: '' }, {
diff --git a/apps/server-brain/src/actions/daily-summary.ts b/apps/server-brain/src/actions/daily-summary.ts
index 8010c40..43dd510 100644
--- a/apps/server-brain/src/actions/daily-summary.ts
+++ b/apps/server-brain/src/actions/daily-summary.ts
@@ -1,10 +1,13 @@
 import {
   dailySummaryInputSchema,
+  dailySummaryModelOutputSchema,
   dailySummaryOutputSchema,
+  parseDailySummaryModelOutput,
   parseDailySummaryInput,
   parseDailySummaryOutput,
-  parseSummarizeOutput,
-  summarizeOutputSchema,
+  type DailySummaryClaim,
+  type DailySummarySource,
+  type DailySummaryVariants,
 } from "../schemas/validation.js";
 import {
   MAX_DAILY_SUMMARY_CONTEXT_BYTES,
@@ -22,6 +25,9 @@ export interface DailySummaryOutput {
   recordCount: number;
   summary: string;
   keyPoints: string[];
+  variants?: DailySummaryVariants;
+  claims?: DailySummaryClaim[];
+  sources?: DailySummarySource[];
 }
 
 const NO_RECORDS_SUMMARY = "No context records found for the selected date.";
@@ -30,8 +36,11 @@ const encoder = new TextEncoder();
 const systemPrompt = [
   "You are the Context OS daily-summary action.",
   "Summarize only the supplied Context OS records for the requested local date.",
-  "Return only a JSON object with exactly these fields:",
-  '{"summary":"string","keyPoints":["string"]}',
+  "Return only a JSON object with summary, keyPoints, variants, and claims fields.",
+  "The variants object must contain quick, standard, and deep answers that use the same facts and sources but different explanation depth.",
+  "Each claim must contain an id, text, sourceIds, and support. sourceIds may contain only record IDs supplied in the records. support must be one of direct, partial, unverified, or conflict.",
+  '{"summary":"string","keyPoints":["string"],"variants":{"quick":"string","standard":"string","deep":"string"},"claims":[{"id":"string","text":"string","sourceIds":["record-id"],"support":"direct|partial|unverified|conflict"}]}',
+  "If a claim cannot be directly supported by the supplied records, mark it unverified and use an empty sourceIds array.",
   "Do not add markdown fences or any other fields.",
 ].join(" ");
 
@@ -41,6 +50,7 @@ function byteLength(value: string): number {
 
 function recordPayload(record: ContextRecord, content: string, includeContext: boolean): string {
   return JSON.stringify({
+    id: record.id,
     recordedAt: record.recordedAt,
     client: record.data.source.client,
     content,
@@ -71,6 +81,40 @@ function fitRecordToBytes(record: ContextRecord, byteBudget: number): string | u
   return undefined;
 }
 
+function createFallbackVariants(summary: string, keyPoints: string[]): DailySummaryVariants {
+  const deep = keyPoints.length > 0 ? `${summary}\n\n${keyPoints.map((point) => `- ${point}`).join("\n")}` : summary;
+  return { quick: summary, standard: summary, deep };
+}
+
+function normalizeClaims(claims: DailySummaryClaim[], validSourceIds: Set<string>): DailySummaryClaim[] {
+  return claims.map((claim) => {
+    const sourceIds = [...new Set(claim.sourceIds)].filter((sourceId) => validSourceIds.has(sourceId));
+    return {
+      ...claim,
+      sourceIds,
+      support: sourceIds.length === 0 ? "unverified" : claim.support,
+    };
+  });
+}
+
+function toSource(record: ContextRecord): DailySummarySource {
+  const browser = record.data.context?.browser;
+  const browserContext = browser && typeof browser === "object" && !Array.isArray(browser)
+    ? browser as Record<string, unknown>
+    : undefined;
+  const title = typeof browserContext?.title === "string" ? browserContext.title.trim() : undefined;
+  const url = typeof browserContext?.url === "string" ? browserContext.url.trim() : undefined;
+  const preview = record.data.content.trim().slice(0, 240) || "(empty record)";
+  return {
+    recordId: record.id,
+    preview,
+    recordedAt: record.recordedAt,
+    client: record.data.source.client,
+    ...(title ? { title } : {}),
+    ...(url ? { url } : {}),
+  };
+}
+
 function buildUserPrompt(input: DailySummaryInput, records: ContextRecord[]): { prompt: string; recordCount: number } {
   const lines: string[] = [];
   let usedBytes = 0;
@@ -112,15 +156,25 @@ export const dailySummaryAction: ActionDefinition<DailySummaryInput, DailySummar
     };
 
     if (prepared.recordCount === 0) {
-      return { ...metadata, summary: NO_RECORDS_SUMMARY, keyPoints: [] };
+      return { ...metadata, summary: NO_RECORDS_SUMMARY, keyPoints: [], sources: [] };
     }
 
     const generated = await dependencies.provider.generateStructured({
       systemPrompt,
       userPrompt: prepared.prompt,
-      outputFormat: JSON.stringify(summarizeOutputSchema),
+      outputFormat: JSON.stringify(dailySummaryModelOutputSchema),
     });
-    return { ...metadata, ...parseSummarizeOutput(generated) };
+    const content = parseDailySummaryModelOutput(generated);
+    const sources = resolvedContext.records.map(toSource);
+    const validSourceIds = new Set(sources.map((source) => source.recordId));
+    return {
+      ...metadata,
+      summary: content.summary,
+      keyPoints: content.keyPoints,
+      variants: content.variants ?? createFallbackVariants(content.summary, content.keyPoints),
+      claims: normalizeClaims(content.claims ?? [], validSourceIds),
+      sources,
+    };
   },
 };
 
diff --git a/apps/server-brain/src/schemas/validation.ts b/apps/server-brain/src/schemas/validation.ts
index fd876e5..82aae9d 100644
--- a/apps/server-brain/src/schemas/validation.ts
+++ b/apps/server-brain/src/schemas/validation.ts
@@ -6,6 +6,44 @@ export const MAX_SUMMARIZE_CONTENT_BYTES = 64 * 1024;
 export const MAX_VOICE_TRANSCRIPT_BYTES = 96 * 1024;
 export const MAX_VOICE_DRAFT_FIELD_BYTES = 16 * 1024;
 export const MAX_DAILY_SUMMARY_TIMEZONE_BYTES = 128;
+export const MAX_DAILY_SUMMARY_CLAIMS = 20;
+export const MAX_DAILY_SUMMARY_SOURCES = 100;
+export const MAX_DAILY_SUMMARY_SOURCE_IDS = 20;
+export const MAX_DAILY_SUMMARY_SOURCE_PREVIEW_BYTES = 1024;
+
+export const DAILY_SUMMARY_LEVELS = ["quick", "standard", "deep"] as const;
+export type DailySummaryLevel = (typeof DAILY_SUMMARY_LEVELS)[number];
+export const DAILY_SUMMARY_SUPPORT_STATUSES = ["direct", "partial", "unverified", "conflict"] as const;
+export type DailySummarySupportStatus = (typeof DAILY_SUMMARY_SUPPORT_STATUSES)[number];
+
+export interface DailySummaryVariants {
+  quick: string;
+  standard: string;
+  deep: string;
+}
+
+export interface DailySummaryClaim {
+  id: string;
+  text: string;
+  sourceIds: string[];
+  support: DailySummarySupportStatus;
+}
+
+export interface DailySummarySource {
+  recordId: string;
+  preview: string;
+  recordedAt: string;
+  client: string;
+  title?: string;
+  url?: string;
+}
+
+export interface DailySummaryModelOutput {
+  summary: string;
+  keyPoints: string[];
+  variants?: DailySummaryVariants;
+  claims?: DailySummaryClaim[];
+}
 
 const encoder = new TextEncoder();
 
@@ -84,15 +122,87 @@ export function parseSummarizeOutput(value: unknown): { summary: string; keyPoin
   return { summary, keyPoints };
 }
 
+function parseDailySummaryVariants(value: unknown, name: string): DailySummaryVariants {
+  const variants = object(value, name);
+  onlyKeys(variants, [...DAILY_SUMMARY_LEVELS], name);
+  return {
+    quick: requiredString(variants.quick, `${name}.quick`, MAX_SUMMARIZE_CONTENT_BYTES),
+    standard: requiredString(variants.standard, `${name}.standard`, MAX_SUMMARIZE_CONTENT_BYTES),
+    deep: requiredString(variants.deep, `${name}.deep`, MAX_SUMMARIZE_CONTENT_BYTES),
+  };
+}
+
+function parseDailySummaryClaims(value: unknown, name: string): DailySummaryClaim[] {
+  if (!Array.isArray(value)) throw new BrainValidationError(`${name} must be an array`);
+  if (value.length > MAX_DAILY_SUMMARY_CLAIMS) throw new BrainValidationError(`${name} must contain at most ${MAX_DAILY_SUMMARY_CLAIMS} items`);
+  return value.map((item, index) => {
+    const claim = object(item, `${name}[${index}]`);
+    onlyKeys(claim, ["id", "text", "sourceIds", "support"], `${name}[${index}]`);
+    if (!Array.isArray(claim.sourceIds)) throw new BrainValidationError(`${name}[${index}].sourceIds must be an array`);
+    if (claim.sourceIds.length > MAX_DAILY_SUMMARY_SOURCE_IDS) {
+      throw new BrainValidationError(`${name}[${index}].sourceIds must contain at most ${MAX_DAILY_SUMMARY_SOURCE_IDS} items`);
+    }
+    const support = claim.support;
+    if (!DAILY_SUMMARY_SUPPORT_STATUSES.includes(support as DailySummarySupportStatus)) {
+      throw new BrainValidationError(`${name}[${index}].support is invalid`);
+    }
+    return {
+      id: requiredString(claim.id, `${name}[${index}].id`, 128).trim(),
+      text: requiredString(claim.text, `${name}[${index}].text`, 4096).trim(),
+      sourceIds: claim.sourceIds.map((sourceId, sourceIndex) => requiredString(sourceId, `${name}[${index}].sourceIds[${sourceIndex}]`, 256).trim()),
+      support: support as DailySummarySupportStatus,
+    };
+  });
+}
+
+function parseDailySummarySources(value: unknown, name: string): DailySummarySource[] {
+  if (!Array.isArray(value)) throw new BrainValidationError(`${name} must be an array`);
+  if (value.length > MAX_DAILY_SUMMARY_SOURCES) throw new BrainValidationError(`${name} must contain at most ${MAX_DAILY_SUMMARY_SOURCES} items`);
+  return value.map((item, index) => {
+    const source = object(item, `${name}[${index}]`);
+    onlyKeys(source, ["recordId", "preview", "recordedAt", "client", "title", "url"], `${name}[${index}]`);
+    return {
+      recordId: requiredString(source.recordId, `${name}[${index}].recordId`, 256).trim(),
+      preview: requiredString(source.preview, `${name}[${index}].preview`, MAX_DAILY_SUMMARY_SOURCE_PREVIEW_BYTES).trim(),
+      recordedAt: requiredString(source.recordedAt, `${name}[${index}].recordedAt`, 64).trim(),
+      client: requiredString(source.client, `${name}[${index}].client`, 128).trim(),
+      ...(source.title === undefined ? {} : { title: requiredString(source.title, `${name}[${index}].title`, 512).trim() }),
+      ...(source.url === undefined ? {} : { url: requiredString(source.url, `${name}[${index}].url`, 2048).trim() }),
+    };
+  });
+}
+
+function parseDailySummaryContent(value: unknown, name: string): DailySummaryModelOutput {
+  const output = object(value, name);
+  onlyKeys(output, ["summary", "keyPoints", "variants", "claims"], name);
+  const summary = requiredString(output.summary, `${name}.summary`, MAX_SUMMARIZE_CONTENT_BYTES);
+  if (!Array.isArray(output.keyPoints)) throw new BrainValidationError(`${name}.keyPoints must be an array`);
+  if (output.keyPoints.length > 20) throw new BrainValidationError(`${name}.keyPoints must contain at most 20 items`);
+  const keyPoints = output.keyPoints.map((point, index) => requiredString(point, `${name}.keyPoints[${index}]`, 4096));
+  return {
+    summary,
+    keyPoints,
+    ...(output.variants === undefined ? {} : { variants: parseDailySummaryVariants(output.variants, `${name}.variants`) }),
+    ...(output.claims === undefined ? {} : { claims: parseDailySummaryClaims(output.claims, `${name}.claims`) }),
+  };
+}
+
+export function parseDailySummaryModelOutput(value: unknown): DailySummaryModelOutput {
+  return parseDailySummaryContent(value, "output");
+}
+
 export function parseDailySummaryOutput(value: unknown): {
   date: string;
   timezone: string;
   recordCount: number;
   summary: string;
   keyPoints: string[];
+  variants?: DailySummaryVariants;
+  claims?: DailySummaryClaim[];
+  sources?: DailySummarySource[];
 } {
   const output = object(value, "output");
-  onlyKeys(output, ["date", "timezone", "recordCount", "summary", "keyPoints"], "output");
+  onlyKeys(output, ["date", "timezone", "recordCount", "summary", "keyPoints", "variants", "claims", "sources"], "output");
   const date = requiredString(output.date, "output.date", 10);
   if (!isValidCalendarDate(date)) throw new BrainValidationError("output.date must be valid YYYY-MM-DD calendar date");
   const timezone = requiredString(output.timezone, "output.timezone", MAX_DAILY_SUMMARY_TIMEZONE_BYTES).trim();
@@ -100,11 +210,19 @@ export function parseDailySummaryOutput(value: unknown): {
   if (!Number.isInteger(output.recordCount) || (output.recordCount as number) < 0 || (output.recordCount as number) > 100) {
     throw new BrainValidationError("output.recordCount must be an integer from 0 to 100");
   }
-  const summary = requiredString(output.summary, "output.summary", MAX_SUMMARIZE_CONTENT_BYTES);
-  if (!Array.isArray(output.keyPoints)) throw new BrainValidationError("output.keyPoints must be an array");
-  if (output.keyPoints.length > 20) throw new BrainValidationError("output.keyPoints must contain at most 20 items");
-  const keyPoints = output.keyPoints.map((point, index) => requiredString(point, `output.keyPoints[${index}]`, 4096));
-  return { date, timezone, recordCount: output.recordCount as number, summary, keyPoints };
+  const content = parseDailySummaryContent({
+    summary: output.summary,
+    keyPoints: output.keyPoints,
+    ...(output.variants === undefined ? {} : { variants: output.variants }),
+    ...(output.claims === undefined ? {} : { claims: output.claims }),
+  }, "output");
+  return {
+    date,
+    timezone,
+    recordCount: output.recordCount as number,
+    ...content,
+    ...(output.sources === undefined ? {} : { sources: parseDailySummarySources(output.sources, "output.sources") }),
+  };
 }
 
 type VoiceContextType = "work" | "decision" | "insight" | "plan" | "question" | "reflection";
@@ -174,11 +292,65 @@ export const dailySummaryOutputSchema = {
     recordCount: { type: "integer", minimum: 0, maximum: 100 },
     summary: { type: "string", minLength: 1, maxBytes: MAX_SUMMARIZE_CONTENT_BYTES },
     keyPoints: { type: "array", items: { type: "string" }, maxItems: 20 },
+    variants: {
+      type: "object",
+      properties: {
+        quick: { type: "string", minLength: 1, maxBytes: MAX_SUMMARIZE_CONTENT_BYTES },
+        standard: { type: "string", minLength: 1, maxBytes: MAX_SUMMARIZE_CONTENT_BYTES },
+        deep: { type: "string", minLength: 1, maxBytes: MAX_SUMMARIZE_CONTENT_BYTES },
+      },
+      required: ["quick", "standard", "deep"],
+      additionalProperties: false,
+    },
+    claims: {
+      type: "array",
+      maxItems: MAX_DAILY_SUMMARY_CLAIMS,
+      items: {
+        type: "object",
+        properties: {
+          id: { type: "string", minLength: 1, maxBytes: 128 },
+          text: { type: "string", minLength: 1, maxBytes: 4096 },
+          sourceIds: { type: "array", items: { type: "string", minLength: 1, maxBytes: 256 }, maxItems: MAX_DAILY_SUMMARY_SOURCE_IDS },
+          support: { type: "string", enum: [...DAILY_SUMMARY_SUPPORT_STATUSES] },
+        },
+        required: ["id", "text", "sourceIds", "support"],
+        additionalProperties: false,
+      },
+    },
+    sources: {
+      type: "array",
+      maxItems: MAX_DAILY_SUMMARY_SOURCES,
+      items: {
+        type: "object",
+        properties: {
+          recordId: { type: "string", minLength: 1, maxBytes: 256 },
+          preview: { type: "string", minLength: 1, maxBytes: MAX_DAILY_SUMMARY_SOURCE_PREVIEW_BYTES },
+          recordedAt: { type: "string", minLength: 1, maxBytes: 64 },
+          client: { type: "string", minLength: 1, maxBytes: 128 },
+          title: { type: "string", minLength: 1, maxBytes: 512 },
+          url: { type: "string", minLength: 1, maxBytes: 2048 },
+        },
+        required: ["recordId", "preview", "recordedAt", "client"],
+        additionalProperties: false,
+      },
+    },
   },
   required: ["date", "timezone", "recordCount", "summary", "keyPoints"],
   additionalProperties: false,
 };
 
+export const dailySummaryModelOutputSchema = {
+  type: "object",
+  properties: {
+    summary: { type: "string", minLength: 1, maxBytes: MAX_SUMMARIZE_CONTENT_BYTES },
+    keyPoints: { type: "array", items: { type: "string" }, maxItems: 20 },
+    variants: dailySummaryOutputSchema.properties.variants,
+    claims: dailySummaryOutputSchema.properties.claims,
+  },
+  required: ["summary", "keyPoints"],
+  additionalProperties: false,
+};
+
 export const voiceContextDraftInputSchema = {
   type: "object",
   properties: {
diff --git a/apps/server-brain/test/daily-summary.test.ts b/apps/server-brain/test/daily-summary.test.ts
index e21f2a4..863f139 100644
--- a/apps/server-brain/test/daily-summary.test.ts
+++ b/apps/server-brain/test/daily-summary.test.ts
@@ -97,6 +97,26 @@ describe("daily-summary context resolution", () => {
       recordCount: 2,
       summary: "Two notes",
       keyPoints: ["morning", "evening"],
+      variants: {
+        quick: "Two notes",
+        standard: "Two notes",
+        deep: "Two notes\n\n- morning\n- evening",
+      },
+      claims: [],
+      sources: [
+        {
+          recordId: "2026-08-13T14:00:00.000Z",
+          preview: "evening note",
+          recordedAt: "2026-08-13T14:00:00.000Z",
+          client: "desktop",
+        },
+        {
+          recordId: "2026-08-12T15:00:00.000Z",
+          preview: "morning note",
+          recordedAt: "2026-08-12T15:00:00.000Z",
+          client: "desktop",
+        },
+      ],
     });
     expect(listRecords).toHaveBeenNthCalledWith(1, { limit: MAX_DAILY_SUMMARY_RECORDS });
     expect(listRecords).toHaveBeenNthCalledWith(2, { limit: MAX_DAILY_SUMMARY_RECORDS, cursor: "next-page" });
@@ -104,6 +124,33 @@ describe("daily-summary context resolution", () => {
     expect(mock.generateStructured.mock.calls[0][0].userPrompt).toContain("evening note");
   });
 
+  it("returns shared answer variants and removes unsupported source IDs", async () => {
+    const mock = provider({
+      summary: "Supported summary",
+      keyPoints: ["One point"],
+      variants: { quick: "Quick", standard: "Standard", deep: "Deep" },
+      claims: [
+        { id: "claim-1", text: "Supported claim", sourceIds: ["source-a", "forged-id"], support: "direct" },
+        { id: "claim-2", text: "Unknown claim", sourceIds: ["forged-id"], support: "direct" },
+      ],
+    });
+    const execution = await runner(mock.value, {
+      listRecords: vi.fn(async () => ({
+        records: [record("2026-08-13T10:00:00.000Z", "source text", "source-a")],
+        nextCursor: null,
+      })),
+    }).run("daily-summary", { date: "2026-08-13", timezone: "Asia/Seoul" });
+
+    expect(execution.result).toMatchObject({
+      variants: { quick: "Quick", standard: "Standard", deep: "Deep" },
+      claims: [
+        { id: "claim-1", sourceIds: ["source-a"], support: "direct" },
+        { id: "claim-2", sourceIds: [], support: "unverified" },
+      ],
+      sources: [{ recordId: "source-a", preview: "source text" }],
+    });
+  });
+
   it("does not call the provider when no records match", async () => {
     const listRecords = vi.fn(async () => ({
       records: [record("2026-08-12T14:59:59.999Z", "outside note")],