diff --git a/desktop/src/components/shared/Modal.test.tsx b/desktop/src/components/shared/Modal.test.tsx
new file mode 100644
index 00000000..69958905
--- /dev/null
+++ b/desktop/src/components/shared/Modal.test.tsx
@@ -0,0 +1,36 @@
+import { fireEvent, render, screen } from '@testing-library/react'
+import { describe, expect, it, vi } from 'vitest'
+import { Modal } from './Modal'
+
+describe('Modal', () => {
+  it('portals the dialog to body so the scrim covers the full app shell', () => {
+    const onClose = vi.fn()
+    const { container } = render(
+      <div data-testid="stacking-parent" className="relative z-10">
+        <Modal open onClose={onClose} title="Provider">
+          <span>Provider form</span>
+        </Modal>
+      </div>,
+    )
+
+    const dialog = screen.getByRole('dialog', { name: 'Provider' })
+
+    expect(container.contains(dialog)).toBe(false)
+    expect(document.body.contains(dialog)).toBe(true)
+  })
+
+  it('closes when the backdrop is clicked', () => {
+    const onClose = vi.fn()
+    render(
+      <Modal open onClose={onClose}>
+        <span>Provider form</span>
+      </Modal>,
+    )
+
+    const backdrop = screen.getByRole('dialog').previousElementSibling
+    expect(backdrop).not.toBeNull()
+    fireEvent.click(backdrop!)
+
+    expect(onClose).toHaveBeenCalledTimes(1)
+  })
+})
diff --git a/desktop/src/components/shared/Modal.tsx b/desktop/src/components/shared/Modal.tsx
index c1f5b278..adaa82c5 100644
--- a/desktop/src/components/shared/Modal.tsx
+++ b/desktop/src/components/shared/Modal.tsx
@@ -1,4 +1,5 @@
 import { useEffect, type ReactNode } from 'react'
+import { createPortal } from 'react-dom'
 
 type ModalProps = {
   open: boolean
@@ -21,7 +22,7 @@ export function Modal({ open, onClose, title, children, width = 560, footer }: M
 
   if (!open) return null
 
-  return (
+  return createPortal(
     <div className="fixed inset-0 z-50 flex items-center justify-center">
       {/* Backdrop */}
       <div
@@ -35,6 +36,7 @@ export function Modal({ open, onClose, title, children, width = 560, footer }: M
         style={{ width, maxWidth: 'calc(100vw - 48px)' }}
         role="dialog"
         aria-modal="true"
+        aria-label={title}
       >
         {title && (
           <div className="flex items-start justify-between gap-4 px-6 pt-6 pb-0">
@@ -60,6 +62,7 @@ export function Modal({ open, onClose, title, children, width = 560, footer }: M
           </div>
         )}
       </div>
-    </div>
+    </div>,
+    document.body,
   )
 }
diff --git a/desktop/src/pages/EmptySession.tsx b/desktop/src/pages/EmptySession.tsx
index fb764f2c..34c0f065 100644
--- a/desktop/src/pages/EmptySession.tsx
+++ b/desktop/src/pages/EmptySession.tsx
@@ -58,7 +58,6 @@ export function EmptySession() {
   const slashItemRefs = useRef<(HTMLButtonElement | null)[]>([])
   const createSession = useSessionStore((state) => state.createSession)
   const sendMessage = useChatStore((state) => state.sendMessage)
-  const setSessionRuntime = useChatStore((state) => state.setSessionRuntime)
   const connectToSession = useChatStore((state) => state.connectToSession)
   const setActiveView = useUIStore((state) => state.setActiveView)
   const addToast = useUIStore((state) => state.addToast)
@@ -233,12 +232,11 @@ export function EmptySession() {
           modelId: settings.currentModel?.id ?? OFFICIAL_DEFAULT_MODEL_ID,
         }
       const sessionId = await createSession(workDir || undefined)
+      useSessionRuntimeStore.getState().setSelection(sessionId, draftSelection)
+      useSessionRuntimeStore.getState().clearSelection(DRAFT_RUNTIME_SELECTION_KEY)
       setActiveView('code')
       useTabStore.getState().openTab(sessionId, 'New Session')
       connectToSession(sessionId)
-      useSessionRuntimeStore.getState().setSelection(sessionId, draftSelection)
-      useSessionRuntimeStore.getState().clearSelection(DRAFT_RUNTIME_SELECTION_KEY)
-      setSessionRuntime(sessionId, draftSelection)
       const attachmentPayload: AttachmentRef[] = attachments.map((attachment) => ({
         type: attachment.type,
         name: attachment.name,
diff --git a/desktop/src/pages/Settings.tsx b/desktop/src/pages/Settings.tsx
index 3e95bc25..5ff8c76a 100644
--- a/desktop/src/pages/Settings.tsx
+++ b/desktop/src/pages/Settings.tsx
@@ -358,6 +358,39 @@ function openExternalUrl(url: string) {
     .catch(() => window.open(url, '_blank', 'noopener,noreferrer'))
 }
 
+const API_KEY_JSON_PLACEHOLDER = '••••••••'
+const API_KEY_JSON_KEYS = ['ANTHROPIC_API_KEY', 'ANTHROPIC_AUTH_TOKEN'] as const
+
+function maskSettingsJsonSecrets(raw: string, apiKey: string): string {
+  if (!apiKey.trim()) return raw
+  try {
+    const parsed = JSON.parse(raw) as { env?: Record<string, unknown> }
+    if (!parsed.env || typeof parsed.env !== 'object') return raw
+    let changed = false
+    for (const key of API_KEY_JSON_KEYS) {
+      if (parsed.env[key] === apiKey) {
+        parsed.env[key] = API_KEY_JSON_PLACEHOLDER
+        changed = true
+      }
+    }
+    return changed ? JSON.stringify(parsed, null, 2) : raw
+  } catch {
+    return raw
+  }
+}
+
+function restoreSettingsJsonSecrets<T>(settings: T, apiKey: string): T {
+  if (!apiKey.trim() || !settings || typeof settings !== 'object') return settings
+  const parsed = settings as { env?: Record<string, unknown> }
+  if (!parsed.env || typeof parsed.env !== 'object') return settings
+  for (const key of API_KEY_JSON_KEYS) {
+    if (parsed.env[key] === API_KEY_JSON_PLACEHOLDER) {
+      parsed.env[key] = apiKey
+    }
+  }
+  return settings
+}
+
 function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderFormProps) {
   const { createProvider, updateProvider, testConfig } = useProviderStore()
   const fetchSettings = useSettingsStore((s) => s.fetchAll)
@@ -446,6 +479,9 @@ function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderF
   const canSubmit = name.trim() && baseUrl.trim() && (mode === 'edit' || !requiresApiKey || apiKey.trim()) && models.main.trim() && !settingsJsonError
   const apiKeyUrl = selectedPreset.apiKeyUrl?.trim()
   const promoText = selectedPreset.promoText?.trim()
+  const displayedSettingsJson = showApiKey
+    ? settingsJson
+    : maskSettingsJsonSecrets(settingsJson, apiKey)
   const apiFormatItems = [
     {
       value: 'anthropic' as const,
@@ -486,7 +522,7 @@ function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderF
       // settings never conflict with the user's global ~/.claude/settings.json.
       if (settingsJson.trim()) {
         try {
-          const parsed = JSON.parse(settingsJson)
+          const parsed = restoreSettingsJsonSecrets(JSON.parse(settingsJson), apiKey)
           const { providersApi } = await import('../api/providers')
           await providersApi.updateSettings(parsed)
         } catch {
@@ -720,12 +756,12 @@ function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderF
         <div>
           <label className="text-sm font-medium text-[var(--color-text-primary)] mb-2 block">{t('settings.providers.settingsJson')}</label>
           <textarea
-            value={settingsJson}
+            value={displayedSettingsJson}
             onChange={(e) => {
               const raw = e.target.value
-              setSettingsJson(raw)
               try {
-                const parsed = JSON.parse(raw)
+                const parsed = restoreSettingsJsonSecrets(JSON.parse(raw), apiKey)
+                setSettingsJson(JSON.stringify(parsed, null, 2))
                 setSettingsJsonError(null)
                 // Auto-fill form fields from parsed JSON env
                 const env = parsed.env as Record<string, string> | undefined
@@ -744,7 +780,10 @@ function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderF
                       }
                     }
                   }
-                  if (env.ANTHROPIC_AUTH_TOKEN && env.ANTHROPIC_AUTH_TOKEN !== '(your API key)') setApiKey(env.ANTHROPIC_AUTH_TOKEN)
+                  const nextApiKey = env.ANTHROPIC_AUTH_TOKEN || env.ANTHROPIC_API_KEY
+                  if (nextApiKey && nextApiKey !== '(your API key)' && nextApiKey !== API_KEY_JSON_PLACEHOLDER) {
+                    setApiKey(nextApiKey)
+                  }
                   const newModels: Partial<ModelMapping> = {}
                   if (env.ANTHROPIC_MODEL) newModels.main = env.ANTHROPIC_MODEL
                   if (env.ANTHROPIC_DEFAULT_HAIKU_MODEL) newModels.haiku = env.ANTHROPIC_DEFAULT_HAIKU_MODEL
@@ -755,6 +794,7 @@ function ProviderFormModal({ open, onClose, mode, provider, presets }: ProviderF
                   }
                 }
               } catch (err) {
+                setSettingsJson(raw)
                 setSettingsJsonError(err instanceof Error ? err.message : 'Invalid JSON')
               }
             }}
diff --git a/src/server/__tests__/conversation-service.test.ts b/src/server/__tests__/conversation-service.test.ts
index 9e812b76..57d64a6b 100644
--- a/src/server/__tests__/conversation-service.test.ts
+++ b/src/server/__tests__/conversation-service.test.ts
@@ -191,6 +191,33 @@ describe('ConversationService', () => {
     expect(env.ANTHROPIC_MODEL).toBe('new-provider-sonnet')
   })
 
+  test('buildChildEnv preserves provider capability overrides from presets', async () => {
+    const providerService = new ProviderService()
+    const provider = await providerService.addProvider({
+      presetId: 'jiekouai',
+      name: 'Jiekou',
+      apiKey: 'provider-key',
+      baseUrl: 'https://api.jiekou.ai/anthropic',
+      apiFormat: 'anthropic',
+      models: {
+        main: 'claude-sonnet-4-6',
+        haiku: 'claude-haiku-4-5-20251001',
+        sonnet: 'claude-sonnet-4-6',
+        opus: 'claude-opus-4-7',
+      },
+    })
+
+    const service = new ConversationService() as any
+    const env = (await service.buildChildEnv('/tmp', undefined, {
+      providerId: provider.id,
+      model: 'claude-sonnet-4-6',
+    })) as Record<string, string>
+
+    expect(env.ANTHROPIC_BASE_URL).toBe('https://api.jiekou.ai/anthropic')
+    expect(env.ANTHROPIC_MODEL).toBe('claude-sonnet-4-6')
+    expect(env.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES).toBe('')
+  })
+
   test('buildChildEnv can force official auth even when a custom default provider exists', async () => {
     const ccHahaDir = path.join(tmpDir, 'cc-haha')
     await fs.mkdir(ccHahaDir, { recursive: true })
diff --git a/src/server/__tests__/conversations.test.ts b/src/server/__tests__/conversations.test.ts
index c0d1f168..04208162 100644
--- a/src/server/__tests__/conversations.test.ts
+++ b/src/server/__tests__/conversations.test.ts
@@ -914,6 +914,115 @@ describe('WebSocket Chat Integration', () => {
     }
   }, 20_000)
 
+  it('should restart a prewarm that began before runtime config arrived', async () => {
+    const providerService = new ProviderService()
+    const provider = await providerService.addProvider({
+      presetId: 'custom',
+      name: 'Provider Late Runtime',
+      apiKey: 'key-late-runtime',
+      baseUrl: 'http://127.0.0.1:1/anthropic',
+      apiFormat: 'anthropic',
+      models: {
+        main: 'late-main',
+        haiku: 'late-haiku',
+        sonnet: 'late-sonnet',
+        opus: 'late-opus',
+      },
+    })
+
+    const createRes = await fetch(`${baseUrl}/api/sessions`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ workDir: process.cwd() }),
+    })
+    expect(createRes.status).toBe(201)
+    const { sessionId } = await createRes.json() as { sessionId: string }
+
+    const originalStartSession = conversationService.startSession.bind(conversationService)
+    const startCalls: Array<{
+      sessionId: string
+      options: { permissionMode?: string; model?: string; effort?: string; providerId?: string | null } | undefined
+    }> = []
+    let releaseFirstStart!: () => void
+    const firstStartGate = new Promise<void>((resolve) => {
+      releaseFirstStart = resolve
+    })
+    let markFirstStart!: () => void
+    const firstStartEntered = new Promise<void>((resolve) => {
+      markFirstStart = resolve
+    })
+
+    conversationService.startSession = (async function patchedStartSession(
+      sid: string,
+      workDir: string,
+      sdkUrl: string,
+      options?: { permissionMode?: string; model?: string; effort?: string; providerId?: string | null },
+    ) {
+      startCalls.push({ sessionId: sid, options })
+      if (startCalls.length === 1) {
+        markFirstStart()
+        await firstStartGate
+      }
+      return originalStartSession(sid, workDir, sdkUrl, options)
+    }) as typeof conversationService.startSession
+
+    const ws = new WebSocket(`${wsUrl}/ws/${sessionId}`)
+    const messages: any[] = []
+    try {
+      await new Promise<void>((resolve, reject) => {
+        const timeout = setTimeout(() => {
+          reject(new Error(`Timed out waiting for late runtime prewarm connection for session ${sessionId}`))
+        }, 5000)
+        ws.onmessage = (event) => {
+          const msg = JSON.parse(event.data as string)
+          messages.push(msg)
+          if (msg.type === 'connected') {
+            clearTimeout(timeout)
+            resolve()
+          }
+          if (msg.type === 'error') {
+            clearTimeout(timeout)
+            reject(new Error(msg.message))
+          }
+        }
+        ws.onerror = () => {
+          clearTimeout(timeout)
+          reject(new Error(`WebSocket error for late runtime prewarm session ${sessionId}`))
+        }
+      })
+
+      ws.send(JSON.stringify({ type: 'prewarm_session' }))
+      await firstStartEntered
+
+      ws.send(JSON.stringify({
+        type: 'set_runtime_config',
+        providerId: provider.id,
+        modelId: 'late-sonnet',
+      }))
+      releaseFirstStart()
+
+      await waitUntil(async () => startCalls.length >= 2, `runtime restart for ${sessionId}`)
+      await waitUntil(
+        async () => messages.some((msg) => msg.type === 'status' && msg.state === 'idle'),
+        `runtime restart idle status for ${sessionId}`,
+      )
+
+      expect(startCalls[0]).toMatchObject({ sessionId })
+      expect(startCalls[0]?.options?.providerId).toBeUndefined()
+      expect(startCalls[1]).toMatchObject({
+        sessionId,
+        options: {
+          providerId: provider.id,
+          model: 'late-sonnet',
+        },
+      })
+    } finally {
+      ws.close()
+      conversationService.startSession = originalStartSession
+      conversationService.stopSession(sessionId)
+    }
+  }, 20_000)
+
   it('should resume streaming to a reconnected client during an active turn', async () => {
     await withMockStreamDelay(150, async () => {
       const sessionId = `chat-reconnect-${crypto.randomUUID()}`
diff --git a/src/server/__tests__/provider-presets.test.ts b/src/server/__tests__/provider-presets.test.ts
index 3078d6ae..6a42c396 100644
--- a/src/server/__tests__/provider-presets.test.ts
+++ b/src/server/__tests__/provider-presets.test.ts
@@ -90,6 +90,7 @@ describe('provider presets API', () => {
     expect(jiekouai?.baseUrl).toBe('https://api.jiekou.ai/anthropic')
     expect(jiekouai?.defaultModels.main).toBe('claude-sonnet-4-6')
     expect(jiekouai?.defaultModels.opus).toBe('claude-opus-4-7')
+    expect(jiekouai?.defaultEnv?.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES).toBe('')
     expect(shengsuanyun?.baseUrl).toBe('https://router.shengsuanyun.com/api')
     expect(shengsuanyun?.defaultModels.main).toBe('anthropic/claude-sonnet-4.6')
     expect(shengsuanyun?.defaultModels.haiku).toBe('anthropic/claude-haiku-4.5:thinking')
@@ -128,6 +129,7 @@ describe('provider presets API', () => {
     expect(shengsuanyun?.defaultEnv).toEqual({
       API_TIMEOUT_MS: '3000000',
       CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC: '1',
+      ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES: '',
     })
     expect(custom?.promoText).toBeUndefined()
   })
diff --git a/src/server/config/providerPresets.json b/src/server/config/providerPresets.json
index 4390af76..d65a5dab 100644
--- a/src/server/config/providerPresets.json
+++ b/src/server/config/providerPresets.json
@@ -42,7 +42,7 @@
     "needsApiKey": true,
     "websiteUrl": "https://open.bigmodel.cn",
     "apiKeyUrl": "https://www.bigmodel.cn/invite?icode=d41B2qi8Z5xNwTGLNPPF3OZLO2QH3C0EBTSr%2BArzMw4%3D",
-    "promoText": ""
+    "promoText": "智谱 GLM 为 cc-haha 用户准备了专属邀请福利，使用此链接注册后可领取新用户权益。"
   },
   {
     "id": "kimi",
@@ -89,7 +89,10 @@
     "websiteUrl": "https://jiekou.ai",
     "apiKeyUrl": "https://jiekou.ai/referral?invited_code=OBNU3K",
     "promoText": "接口AI为 cc-haha 的用户提供官方资源与稳定高性能体验，订阅包价格为官方 8 折；绑定 GitHub 后还可领取 3 美元优惠券。",
-    "featured": true
+    "featured": true,
+    "defaultEnv": {
+      "ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES": ""
+    }
   },
   {
     "id": "shengsuanyun",
@@ -109,7 +112,8 @@
     "featured": true,
     "defaultEnv": {
       "API_TIMEOUT_MS": "3000000",
-      "CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC": "1"
+      "CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC": "1",
+      "ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES": ""
     }
   },
   {
diff --git a/src/server/services/conversationService.ts b/src/server/services/conversationService.ts
index 4a3a2ab2..ff5f6155 100644
--- a/src/server/services/conversationService.ts
+++ b/src/server/services/conversationService.ts
@@ -610,8 +610,11 @@ export class ConversationService {
       'ANTHROPIC_AUTH_TOKEN',
       'ANTHROPIC_MODEL',
       'ANTHROPIC_DEFAULT_HAIKU_MODEL',
+      'ANTHROPIC_DEFAULT_HAIKU_MODEL_SUPPORTED_CAPABILITIES',
       'ANTHROPIC_DEFAULT_SONNET_MODEL',
+      'ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES',
       'ANTHROPIC_DEFAULT_OPUS_MODEL',
+      'ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIES',
     ] as const
 
     const cleanEnv = { ...process.env }
@@ -730,8 +733,11 @@ export class ConversationService {
         'ANTHROPIC_AUTH_TOKEN',
         'ANTHROPIC_MODEL',
         'ANTHROPIC_DEFAULT_HAIKU_MODEL',
+        'ANTHROPIC_DEFAULT_HAIKU_MODEL_SUPPORTED_CAPABILITIES',
         'ANTHROPIC_DEFAULT_SONNET_MODEL',
+        'ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES',
         'ANTHROPIC_DEFAULT_OPUS_MODEL',
+        'ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIES',
       ].some((key) => typeof env[key] === 'string' && env[key]!.trim().length > 0)
     } catch {
       return false
diff --git a/src/server/services/providerService.ts b/src/server/services/providerService.ts
index e80739e0..c20ff2c1 100644
--- a/src/server/services/providerService.ts
+++ b/src/server/services/providerService.ts
@@ -33,8 +33,11 @@ const MANAGED_ENV_KEYS = [
   'ANTHROPIC_AUTH_TOKEN',
   'ANTHROPIC_MODEL',
   'ANTHROPIC_DEFAULT_HAIKU_MODEL',
+  'ANTHROPIC_DEFAULT_HAIKU_MODEL_SUPPORTED_CAPABILITIES',
   'ANTHROPIC_DEFAULT_SONNET_MODEL',
+  'ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES',
   'ANTHROPIC_DEFAULT_OPUS_MODEL',
+  'ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIES',
 ] as const
 
 const DEFAULT_INDEX: ProvidersIndex = { activeId: null, providers: [] }
diff --git a/src/server/ws/handler.ts b/src/server/ws/handler.ts
index 49a99996..53acb867 100644
--- a/src/server/ws/handler.ts
+++ b/src/server/ws/handler.ts
@@ -460,6 +460,21 @@ async function handleSetRuntimeConfig(
   }
 
   if (!conversationService.hasSession(sessionId)) {
+    const pendingStartup = sessionStartupPromises.get(sessionId)
+    if (pendingStartup) {
+      await enqueueRuntimeTransition(sessionId, async () => {
+        await pendingStartup.catch(() => undefined)
+        const currentOverride = runtimeOverrides.get(sessionId)
+        if (
+          currentOverride?.providerId !== nextOverride.providerId ||
+          currentOverride.modelId !== nextOverride.modelId ||
+          !conversationService.hasSession(sessionId)
+        ) {
+          return
+        }
+        await restartSessionWithRuntimeConfig(ws, sessionId)
+      })
+    }
     return
   }
 
diff --git a/src/utils/__tests__/thinking.test.ts b/src/utils/__tests__/thinking.test.ts
new file mode 100644
index 00000000..c921f70a
--- /dev/null
+++ b/src/utils/__tests__/thinking.test.ts
@@ -0,0 +1,77 @@
+import { afterEach, beforeEach, describe, expect, test } from 'bun:test'
+import { get3PModelCapabilityOverride } from '../model/modelSupportOverrides.js'
+import { modelSupportsAdaptiveThinking, modelSupportsThinking } from '../thinking.js'
+
+describe('provider-aware thinking support', () => {
+  let originalBaseUrl: string | undefined
+  let originalSonnetModel: string | undefined
+  let originalSonnetCapabilities: string | undefined
+  let originalBedrock: string | undefined
+  let originalVertex: string | undefined
+  let originalFoundry: string | undefined
+
+  beforeEach(() => {
+    originalBaseUrl = process.env.ANTHROPIC_BASE_URL
+    originalSonnetModel = process.env.ANTHROPIC_DEFAULT_SONNET_MODEL
+    originalSonnetCapabilities = process.env.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES
+    originalBedrock = process.env.CLAUDE_CODE_USE_BEDROCK
+    originalVertex = process.env.CLAUDE_CODE_USE_VERTEX
+    originalFoundry = process.env.CLAUDE_CODE_USE_FOUNDRY
+
+    delete process.env.CLAUDE_CODE_USE_BEDROCK
+    delete process.env.CLAUDE_CODE_USE_VERTEX
+    delete process.env.CLAUDE_CODE_USE_FOUNDRY
+  })
+
+  afterEach(() => {
+    restoreEnv('ANTHROPIC_BASE_URL', originalBaseUrl)
+    restoreEnv('ANTHROPIC_DEFAULT_SONNET_MODEL', originalSonnetModel)
+    restoreEnv('ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES', originalSonnetCapabilities)
+    restoreEnv('CLAUDE_CODE_USE_BEDROCK', originalBedrock)
+    restoreEnv('CLAUDE_CODE_USE_VERTEX', originalVertex)
+    restoreEnv('CLAUDE_CODE_USE_FOUNDRY', originalFoundry)
+    clearCapabilityCache()
+  })
+
+  test('does not assume adaptive thinking for Anthropic-compatible third-party base URLs', () => {
+    process.env.ANTHROPIC_BASE_URL = 'https://api.jiekou.ai/anthropic'
+    delete process.env.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES
+    clearCapabilityCache()
+
+    expect(modelSupportsAdaptiveThinking('claude-sonnet-4-6')).toBe(false)
+  })
+
+  test('honors explicit empty provider capability overrides', () => {
+    process.env.ANTHROPIC_BASE_URL = 'https://api.jiekou.ai/anthropic'
+    process.env.ANTHROPIC_DEFAULT_SONNET_MODEL = 'claude-sonnet-4-6'
+    process.env.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES = ''
+    clearCapabilityCache()
+
+    expect(get3PModelCapabilityOverride('claude-sonnet-4-6', 'thinking')).toBe(false)
+    expect(modelSupportsThinking('claude-sonnet-4-6')).toBe(false)
+    expect(modelSupportsAdaptiveThinking('claude-sonnet-4-6')).toBe(false)
+  })
+
+  test('keeps first-party Anthropic Sonnet adaptive thinking enabled', () => {
+    process.env.ANTHROPIC_BASE_URL = 'https://api.anthropic.com'
+    delete process.env.ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIES
+    clearCapabilityCache()
+
+    expect(modelSupportsThinking('claude-sonnet-4-6')).toBe(true)
+    expect(modelSupportsAdaptiveThinking('claude-sonnet-4-6')).toBe(true)
+  })
+})
+
+function restoreEnv(key: string, value: string | undefined) {
+  if (value === undefined) {
+    delete process.env[key]
+  } else {
+    process.env[key] = value
+  }
+}
+
+function clearCapabilityCache() {
+  ;(get3PModelCapabilityOverride as typeof get3PModelCapabilityOverride & {
+    cache?: { clear?: () => void }
+  }).cache?.clear?.()
+}
diff --git a/src/utils/model/modelSupportOverrides.ts b/src/utils/model/modelSupportOverrides.ts
index d3003272..56cb2519 100644
--- a/src/utils/model/modelSupportOverrides.ts
+++ b/src/utils/model/modelSupportOverrides.ts
@@ -1,5 +1,5 @@
 import memoize from 'lodash-es/memoize.js'
-import { getAPIProvider } from './providers.js'
+import { getAPIProvider, isFirstPartyAnthropicBaseUrl } from './providers.js'
 
 export type ModelCapabilityOverride =
   | 'effort'
@@ -29,7 +29,7 @@ const TIERS = [
  */
 export const get3PModelCapabilityOverride = memoize(
   (model: string, capability: ModelCapabilityOverride): boolean | undefined => {
-    if (getAPIProvider() === 'firstParty') {
+    if (getAPIProvider() === 'firstParty' && isFirstPartyAnthropicBaseUrl()) {
       return undefined
     }
     const m = model.toLowerCase()
diff --git a/src/utils/thinking.ts b/src/utils/thinking.ts
index b37fe42d..506c3692 100644
--- a/src/utils/thinking.ts
+++ b/src/utils/thinking.ts
@@ -4,7 +4,7 @@ import { feature } from 'bun:bundle'
 import { getFeatureValue_CACHED_MAY_BE_STALE } from '../services/analytics/growthbook.js'
 import { getCanonicalName } from './model/model.js'
 import { get3PModelCapabilityOverride } from './model/modelSupportOverrides.js'
-import { getAPIProvider } from './model/providers.js'
+import { getAPIProvider, isFirstPartyAnthropicBaseUrl } from './model/providers.js'
 import { getSettingsWithErrors } from './settings/settings.js'
 
 export type ThinkingConfig =
@@ -102,7 +102,10 @@ export function modelSupportsThinking(model: string): boolean {
   const canonical = getCanonicalName(model)
   const provider = getAPIProvider()
   // 1P and Foundry: all Claude 4+ models (including Haiku 4.5)
-  if (provider === 'foundry' || provider === 'firstParty') {
+  if (
+    provider === 'foundry' ||
+    (provider === 'firstParty' && isFirstPartyAnthropicBaseUrl())
+  ) {
     return !canonical.includes('claude-3-')
   }
   // 3P (Bedrock/Vertex): only Opus 4+ and Sonnet 4+
@@ -116,6 +119,14 @@ export function modelSupportsAdaptiveThinking(model: string): boolean {
     return supported3P
   }
   const canonical = getCanonicalName(model)
+  const provider = getAPIProvider()
+  const isFirstPartyBaseUrl =
+    provider === 'firstParty' && isFirstPartyAnthropicBaseUrl()
+
+  if (!isFirstPartyBaseUrl && provider !== 'foundry') {
+    return false
+  }
+
   // Supported by a subset of Claude 4 models
   if (canonical.includes('opus-4-6') || canonical.includes('sonnet-4-6')) {
     return true
@@ -139,7 +150,6 @@ export function modelSupportsAdaptiveThinking(model: string): boolean {
   // Default to true for unknown model strings on 1P and Foundry (because Foundry
   // is a proxy). Do not default to true for other 3P as they have different formats
   // for their model strings.
-  const provider = getAPIProvider()
   return provider === 'firstParty' || provider === 'foundry'
 }