feat(zai): add Z.AI GLM Coding Plan provider preset (#896)

* feat(zai): add Z.AI GLM Coding Plan provider preset

Add dedicated Z.AI provider support for the GLM Coding Plan, enabling
use of GLM-5.1, GLM-5-Turbo, GLM-4.7, and GLM-4.5-Air models through
the OpenAI-compatible shim with proper thinking mode (reasoning_content),
max_tokens handling, and context window sizing.

* fix(zai): unify GLM max output token limits across casing variants

glm-5/glm-4.7 had conservative 16K max output while GLM-5/GLM-4.7
had 131K. Use consistent Z.AI coding plan limits for all GLM variants.

* fix(zai): restore DashScope GLM limits, enable GLM thinking support

- Restore lowercase glm-5/glm-4.7 to 16_384 max output (DashScope limits)
  while keeping Z.AI coding plan high limits on uppercase GLM-* keys only
- Add GLM model support to modelSupportsThinking() so reasoning_content
  is enabled when using GLM-5.x/GLM-4.7 models on Z.AI

* fix(zai): tighten GLM regexes, fix misleading context window comment

- Use precise regex in thinking.ts: exact GLM model matches only,
  no false positives on glm-50/glm-4, includes glm-4.5-air
- Use uppercase-only match in StartupScreen rawModel fallback so
  DashScope lowercase glm-* models aren't mislabeled as Z.AI
- Clarify context window comment: lowercase glm-5.1/glm-5-turbo/
  glm-4.5-air are Z.AI-specific aliases, not DashScope

* fix(zai): scope GLM detection to Z.AI

* improve readability of max_completion_tokens check

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

.env.example

@@ -150,6 +150,10 @@ ANTHROPIC_API_KEY=sk-ant-your-key-here
 # OPENAI_MODEL=deepseek-v4-flash
 # Optional: OPENAI_MODEL=deepseek-v4-pro
 # Legacy aliases also work: deepseek-chat and deepseek-reasoner
+# For Z.AI GLM Coding Plan, set:
+# OPENAI_BASE_URL=https://api.z.ai/api/coding/paas/v4
+# OPENAI_MODEL=GLM-5.1
+# Optional: OPENAI_MODEL=GLM-5-Turbo, GLM-4.7, or GLM-4.5-Air
 
 # Use a custom OpenAI-compatible endpoint (optional — defaults to api.openai.com)
 # OPENAI_BASE_URL=https://api.openai.com/v1

src/components/ProviderManager.test.tsx

@@ -125,6 +125,7 @@ const PRESET_ORDER = [
   'OpenAI',
   'OpenRouter',
   'Together AI',
+  'Z.AI - GLM Coding Plan',
   'Custom',
 ] as const
 

src/components/ProviderManager.tsx

@@ -1345,6 +1345,11 @@ export function ProviderManager({ mode, onDone }: Props): React.ReactNode {
         label: 'Together AI',
         description: 'Together chat/completions endpoint',
       },
+      {
+        value: 'zai',
+        label: 'Z.AI - GLM Coding Plan',
+        description: 'Z.AI GLM coding subscription endpoint',
+      },
       {
         value: 'custom',
         label: 'Custom',

src/components/StartupScreen.test.ts

@@ -116,6 +116,11 @@ describe('detectProvider — direct vendor endpoints', () => {
     expect(detectProvider().name).toBe('Mistral')
   })
 
+  test('api.z.ai labels as Z.AI GLM', () => {
+    setupOpenAIMode('https://api.z.ai/api/coding/paas/v4', 'GLM-5.1')
+    expect(detectProvider().name).toBe('Z.AI - GLM')
+  })
+
   test('default OpenAI URL + gpt-4o labels as OpenAI', () => {
     setupOpenAIMode('https://api.openai.com/v1', 'gpt-4o')
     expect(detectProvider().name).toBe('OpenAI')
@@ -149,6 +154,21 @@ describe('detectProvider — rawModel fallback when URL is generic', () => {
     setupOpenAIMode('https://my-proxy.internal/v1', 'mistral-large-latest')
     expect(detectProvider().name).toBe('Mistral')
   })
+
+  test('custom proxy + exact uppercase GLM ID falls back to Z.AI GLM', () => {
+    setupOpenAIMode('https://my-proxy.internal/v1', 'GLM-5.1')
+    expect(detectProvider().name).toBe('Z.AI - GLM')
+  })
+
+  test('custom proxy + lowercase glm ID stays generic OpenAI', () => {
+    setupOpenAIMode('https://my-proxy.internal/v1', 'glm-5.1')
+    expect(detectProvider().name).toBe('OpenAI')
+  })
+
+  test('DashScope lowercase glm ID is not mislabeled as Z.AI', () => {
+    setupOpenAIMode('https://dashscope.aliyuncs.com/compatible-mode/v1', 'glm-5.1')
+    expect(detectProvider().name).toBe('OpenAI')
+  })
 })
 
 // --- Explicit env flags win over URL heuristics ---

src/components/StartupScreen.ts

@@ -9,6 +9,7 @@ import { isLocalProviderUrl, resolveProviderRequest } from '../services/api/prov
 import { getLocalOpenAICompatibleProviderLabel } from '../utils/providerDiscovery.js'
 import { getSettings_DEPRECATED } from '../utils/settings/settings.js'
 import { parseUserSpecifiedModel } from '../utils/model/model.js'
+import { containsExactZaiGlmModelId, isZaiBaseUrl } from '../utils/zaiProvider.js'
 
 declare const MACRO: { VERSION: string; DISPLAY_VERSION?: string }
 
@@ -137,6 +138,7 @@ export function detectProvider(): { name: string; model: string; baseUrl: string
     else if (/api\.kimi\.com/i.test(baseUrl)) name = 'Moonshot AI - Kimi Code'
     else if (/moonshot/i.test(baseUrl)) name = 'Moonshot AI - API'
     else if (/deepseek/i.test(baseUrl)) name = 'DeepSeek'
+    else if (isZaiBaseUrl(baseUrl)) name = 'Z.AI - GLM'
     else if (/mistral/i.test(baseUrl)) name = 'Mistral'
     // rawModel fallback — fires only when base URL is generic/custom.
     else if (/nvidia/i.test(rawModel)) name = 'NVIDIA NIM'
@@ -146,6 +148,7 @@ export function detectProvider(): { name: string; model: string; baseUrl: string
     else if (/\bkimi-k/i.test(rawModel) || /moonshot/i.test(rawModel))
       name = 'Moonshot AI - API'
     else if (/deepseek/i.test(rawModel)) name = 'DeepSeek'
+    else if (containsExactZaiGlmModelId(rawModel)) name = 'Z.AI - GLM'
     else if (/mistral/i.test(rawModel)) name = 'Mistral'
     else if (/llama/i.test(rawModel)) name = 'Meta Llama'
     else if (/bankr/i.test(baseUrl)) name = 'Bankr'

src/services/api/openaiShim.test.ts

@@ -3991,3 +3991,79 @@ test('preserves mixed text and image tool results as multipart content', async (
   expect(content[0].type).toBe('text')
   expect(content[1].type).toBe('image_url')
 })
+
+test('Z.AI: uses max_tokens (not max_completion_tokens) and strips store', async () => {
+  process.env.OPENAI_BASE_URL = 'https://api.z.ai/api/coding/paas/v4'
+  process.env.OPENAI_API_KEY = 'sk-zai-test'
+
+  let requestBody: Record<string, unknown> | undefined
+  globalThis.fetch = (async (_input, init) => {
+    requestBody = JSON.parse(String(init?.body))
+    return new Response(
+      JSON.stringify({
+        id: 'chatcmpl-1',
+        model: 'GLM-5.1',
+        choices: [
+          { message: { role: 'assistant', content: 'ok' }, finish_reason: 'stop' },
+        ],
+        usage: { prompt_tokens: 3, completion_tokens: 1, total_tokens: 4 },
+      }),
+      { headers: { 'Content-Type': 'application/json' } },
+    )
+  }) as FetchType
+
+  const client = createOpenAIShimClient({}) as OpenAIShimClient
+  await client.beta.messages.create({
+    model: 'GLM-5.1',
+    system: 'you are glm',
+    messages: [{ role: 'user', content: 'hi' }],
+    max_tokens: 256,
+    stream: false,
+  })
+
+  expect(requestBody?.max_tokens).toBe(256)
+  expect(requestBody?.max_completion_tokens).toBeUndefined()
+  expect(requestBody?.store).toBeUndefined()
+})
+
+test('Z.AI: thinking mode enabled when requested', async () => {
+  process.env.OPENAI_BASE_URL = 'https://api.z.ai/api/coding/paas/v4'
+  process.env.OPENAI_API_KEY = 'sk-zai-test'
+
+  let requestBody: Record<string, unknown> | undefined
+  globalThis.fetch = (async (_input, init) => {
+    requestBody = JSON.parse(String(init?.body))
+    return new Response(
+      JSON.stringify({
+        id: 'chatcmpl-1',
+        model: 'GLM-5.1',
+        choices: [
+          {
+            message: {
+              role: 'assistant',
+              content: null,
+              reasoning_content: 'Let me think...',
+            },
+            finish_reason: 'stop',
+          },
+        ],
+        usage: { prompt_tokens: 3, completion_tokens: 1, total_tokens: 4 },
+      }),
+      { headers: { 'Content-Type': 'application/json' } },
+    )
+  }) as FetchType
+
+  const client = createOpenAIShimClient({}) as OpenAIShimClient
+  await client.beta.messages.create({
+    model: 'GLM-5.1',
+    system: 'you are glm',
+    messages: [{ role: 'user', content: 'think hard' }],
+    max_tokens: 1024,
+    stream: false,
+    thinking: { type: 'enabled', budget_tokens: 1024 },
+  })
+
+  expect((requestBody?.thinking as Record<string, string>)?.type).toBe('enabled')
+  expect(requestBody?.max_completion_tokens).toBeUndefined()
+  expect(requestBody?.max_tokens).toBe(1024)
+})

src/services/api/openaiShim.ts

@@ -64,6 +64,7 @@ import {
 } from './openaiErrorClassification.js'
 import { sanitizeSchemaForOpenAICompat } from '../../utils/schemaSanitizer.js'
 import { redactSecretValueForDisplay } from '../../utils/providerProfile.js'
+import { isZaiBaseUrl } from '../../utils/zaiProvider.js'
 import {
   normalizeToolArguments,
   hasToolFieldMapping,
@@ -93,7 +94,6 @@ const KIMI_CODE_API_HOST = 'api.kimi.com'
 const DEEPSEEK_API_HOSTS = new Set([
   'api.deepseek.com',
 ])
-
 const COPILOT_HEADERS: Record<string, string> = {
   'User-Agent': 'GitHubCopilotChat/0.26.7',
   'Editor-Version': 'vscode/1.99.3',
@@ -1514,7 +1514,8 @@ class OpenAIShimMessages {
       // thinking block we captured on the inbound response.
       preserveReasoningContent:
         isMoonshotCompatibleBaseUrl(request.baseUrl) ||
-        isDeepSeekBaseUrl(request.baseUrl),
+        isDeepSeekBaseUrl(request.baseUrl) ||
+        isZaiBaseUrl(request.baseUrl),
     })
 
     const body: Record<string, unknown> = {
@@ -1553,8 +1554,19 @@ class OpenAIShimMessages {
 
     const isMoonshot = isMoonshotCompatibleBaseUrl(request.baseUrl)
     const isDeepSeek = isDeepSeekBaseUrl(request.baseUrl)
+    const isZai = isZaiBaseUrl(request.baseUrl)
 
-    if ((isGithub || isMistral || isLocal || isMoonshot || isDeepSeek) && body.max_completion_tokens !== undefined) {
+    if (
+      (
+        isGithub ||
+        isMistral ||
+        isLocal ||
+        isMoonshot ||
+        isDeepSeek ||
+        isZai
+      ) &&
+      body.max_completion_tokens !== undefined
+    ) {
       body.max_tokens = body.max_completion_tokens
       delete body.max_completion_tokens
     }
@@ -1562,10 +1574,10 @@ class OpenAIShimMessages {
     // mistral and gemini don't recognize body.store — Gemini returns 400
     // "Invalid JSON payload received. Unknown name 'store': Cannot find field."
     // Moonshot direct API, Kimi Code's OpenAI-compatible coding endpoint,
-    // and DeepSeek have not published support for the parameter either;
+    // DeepSeek, and Z.AI have not published support for the parameter either;
     // strip it preemptively to avoid the same class of error on strict-parse
     // providers.
-    if (isMistral || isGeminiMode() || isMoonshot || isDeepSeek) {
+    if (isMistral || isGeminiMode() || isMoonshot || isDeepSeek || isZai) {
       delete body.store
     }
 
@@ -1593,6 +1605,17 @@ class OpenAIShimMessages {
       }
     }
 
+    // Z.AI uses the same thinking format as DeepSeek: { type: "enabled" | "disabled" }
+    // with reasoning_content in responses.
+    if (isZai) {
+      const requestedThinkingType = (params.thinking as { type?: string } | undefined)?.type
+      if (requestedThinkingType && requestedThinkingType !== 'disabled') {
+        body.thinking = { type: 'enabled' }
+      } else if (requestedThinkingType === 'disabled') {
+        body.thinking = { type: 'disabled' }
+      }
+    }
+
     if (params.tools && params.tools.length > 0) {
       const converted = convertTools(
         params.tools as Array<{

src/utils/context.test.ts

@@ -1,4 +1,4 @@
-import { afterEach, expect, test } from 'bun:test'
+import { afterEach, beforeEach, expect, test } from 'bun:test'
 
 import { getMaxOutputTokensForModel } from '../services/api/claude.ts'
 import {
@@ -12,6 +12,12 @@ const originalEnv = {
   OPENAI_MODEL: process.env.OPENAI_MODEL,
 }
 
+beforeEach(() => {
+  delete process.env.CLAUDE_CODE_USE_OPENAI
+  delete process.env.CLAUDE_CODE_MAX_OUTPUT_TOKENS
+  delete process.env.OPENAI_MODEL
+})
+
 afterEach(() => {
   if (originalEnv.CLAUDE_CODE_USE_OPENAI === undefined) {
     delete process.env.CLAUDE_CODE_USE_OPENAI
@@ -265,6 +271,43 @@ test('DashScope glm-4.7 uses provider-specific context and output caps', () => {
   })
 })
 
+test('Z.AI uppercase GLM models use Coding Plan output caps', () => {
+  process.env.CLAUDE_CODE_USE_OPENAI = '1'
+  delete process.env.CLAUDE_CODE_MAX_OUTPUT_TOKENS
+
+  expect(getContextWindowForModel('GLM-5.1')).toBe(202_752)
+  expect(getModelMaxOutputTokens('GLM-5.1')).toEqual({
+    default: 131_072,
+    upperLimit: 131_072,
+  })
+  expect(getModelMaxOutputTokens('GLM-5-Turbo')).toEqual({
+    default: 131_072,
+    upperLimit: 131_072,
+  })
+  expect(getModelMaxOutputTokens('GLM-4.5-Air')).toEqual({
+    default: 65_536,
+    upperLimit: 65_536,
+  })
+})
+
+test('lowercase GLM aliases keep conservative output caps', () => {
+  process.env.CLAUDE_CODE_USE_OPENAI = '1'
+  delete process.env.CLAUDE_CODE_MAX_OUTPUT_TOKENS
+
+  expect(getModelMaxOutputTokens('glm-5.1')).toEqual({
+    default: 16_384,
+    upperLimit: 16_384,
+  })
+  expect(getModelMaxOutputTokens('glm-5-turbo')).toEqual({
+    default: 16_384,
+    upperLimit: 16_384,
+  })
+  expect(getModelMaxOutputTokens('glm-4.5-air')).toEqual({
+    default: 16_384,
+    upperLimit: 16_384,
+  })
+})
+
 test('DashScope models clamp oversized max output overrides to the provider limit', () => {
   process.env.CLAUDE_CODE_USE_OPENAI = '1'
   process.env.CLAUDE_CODE_MAX_OUTPUT_TOKENS = '100000'
@@ -275,4 +318,5 @@ test('DashScope models clamp oversized max output overrides to the provider limi
   expect(getMaxOutputTokensForModel('qwen3-max')).toBe(32_768)
   expect(getMaxOutputTokensForModel('kimi-k2.5')).toBe(32_768)
   expect(getMaxOutputTokensForModel('glm-5')).toBe(16_384)
+  expect(getMaxOutputTokensForModel('glm-5.1')).toBe(16_384)
 })

src/utils/model/openaiContextWindows.ts

@@ -232,6 +232,15 @@ const OPENAI_CONTEXT_WINDOWS: Record<string, number> = {
   'kimi-k2.5':                262_144,
   'glm-5':                    202_752,
   'glm-4.7':                  202_752,
+  'glm-5.1':                  202_752,
+  'glm-5-turbo':              202_752,
+  'glm-4.5-air':              128_000,
+  // Z.AI Coding Plan models (uppercase variants)
+  'GLM-5.1':                  202_752,
+  'GLM-5-Turbo':              202_752,
+  'GLM-5':                    202_752,
+  'GLM-4.7':                  202_752,
+  'GLM-4.5-Air':              128_000,
 
   // Moonshot AI direct API (api.moonshot.ai/v1). Values from Moonshot's
   // published model card — all K2 tier share 256K context. Prefix matching
@@ -420,8 +429,18 @@ const OPENAI_MAX_OUTPUT_TOKENS: Record<string, number> = {
   'qwen3-max':                 32_768,
   'qwen3-max-2026-01-23':      32_768,
   'kimi-k2.5':                 32_768,
+  // GLM models — lowercase aliases stay on conservative DashScope-style
+  // limits; Z.AI Coding Plan's exact uppercase GLM-* IDs use higher limits.
   'glm-5':                     16_384,
   'glm-4.7':                   16_384,
+  'glm-5.1':                    16_384,
+  'glm-5-turbo':                16_384,
+  'glm-4.5-air':                16_384,
+  'GLM-5':                     131_072,
+  'GLM-5.1':                   131_072,
+  'GLM-5-Turbo':               131_072,
+  'GLM-4.7':                   131_072,
+  'GLM-4.5-Air':                65_536,
 
   // Moonshot AI direct API
   'kimi-for-coding':           32_768,

src/utils/providerDiscovery.ts

@@ -1,5 +1,6 @@
 import type { OllamaModelDescriptor } from './providerRecommendation.ts'
 import { DEFAULT_OPENAI_BASE_URL } from '../services/api/providerConfig.js'
+import { isZaiBaseUrl } from './zaiProvider.js'
 
 export const DEFAULT_OLLAMA_BASE_URL = 'http://localhost:11434'
 export const DEFAULT_ATOMIC_CHAT_BASE_URL = 'http://127.0.0.1:1337'
@@ -205,6 +206,10 @@ export function getLocalOpenAICompatibleProviderLabel(baseUrl?: string): string
     if (host.includes('bankr') || haystack.includes('bankr')) {
       return 'Bankr'
     }
+    // Z.AI GLM Coding Plan
+    if (isZaiBaseUrl(parsed.href)) {
+      return 'Z.AI - GLM'
+    }
     // Moonshot AI direct API
     if (
       host.includes('moonshot') ||

src/utils/providerFlag.ts

@@ -15,6 +15,7 @@
 export const VALID_PROVIDERS = [
   'anthropic',
   'bankr',
+  'zai',
   'openai',
   'gemini',
   'mistral',
@@ -159,6 +160,13 @@ export function applyProviderFlag(
         process.env.OPENAI_API_KEY = process.env.BNKR_API_KEY
       }
       break
+
+    case 'zai':
+      process.env.CLAUDE_CODE_USE_OPENAI = '1'
+      process.env.OPENAI_BASE_URL ??= 'https://api.z.ai/api/coding/paas/v4'
+      process.env.OPENAI_MODEL ??= 'GLM-5.1'
+      if (model) process.env.OPENAI_MODEL = model
+      break
   }
 
   return {}

src/utils/providerProfiles.test.ts

@@ -625,6 +625,18 @@ describe('getProviderPresetDefaults', () => {
     )
     expect(defaults.requiresApiKey).toBe(true)
   })
+
+  test('zai preset defaults to Z.AI GLM Coding Plan endpoint', async () => {
+    const { getProviderPresetDefaults } = await importFreshProviderProfileModules()
+
+    const defaults = getProviderPresetDefaults('zai')
+
+    expect(defaults.provider).toBe('openai')
+    expect(defaults.name).toBe('Z.AI - GLM Coding Plan')
+    expect(defaults.baseUrl).toBe('https://api.z.ai/api/coding/paas/v4')
+    expect(defaults.model).toBe('GLM-5.1, GLM-5-Turbo, GLM-4.7, GLM-4.5-Air')
+    expect(defaults.requiresApiKey).toBe(true)
+  })
 })
 
 describe('setActiveProviderProfile', () => {

src/utils/providerProfiles.ts

@@ -36,6 +36,7 @@ export type ProviderPreset =
   | 'custom'
   | 'nvidia-nim'
   | 'minimax'
+  | 'zai'
   | 'bankr'
   | 'atomic-chat'
 
@@ -317,6 +318,15 @@ export function getProviderPresetDefaults(
         apiKey: process.env.BNKR_API_KEY ?? '',
         requiresApiKey: true,
       }
+    case 'zai':
+      return {
+        provider: 'openai',
+        name: 'Z.AI - GLM Coding Plan',
+        baseUrl: 'https://api.z.ai/api/coding/paas/v4',
+        model: 'GLM-5.1, GLM-5-Turbo, GLM-4.7, GLM-4.5-Air',
+        apiKey: '',
+        requiresApiKey: true,
+      }
     case 'ollama':
     default:
       return {

src/utils/thinking.test.ts

@@ -0,0 +1,64 @@
+import { afterEach, beforeEach, describe, expect, test } from 'bun:test'
+import { modelSupportsThinking } from './thinking.js'
+
+const ENV_KEYS = [
+  'CLAUDE_CODE_USE_OPENAI',
+  'CLAUDE_CODE_USE_GEMINI',
+  'CLAUDE_CODE_USE_GITHUB',
+  'CLAUDE_CODE_USE_MISTRAL',
+  'CLAUDE_CODE_USE_BEDROCK',
+  'CLAUDE_CODE_USE_VERTEX',
+  'CLAUDE_CODE_USE_FOUNDRY',
+  'OPENAI_BASE_URL',
+  'OPENAI_API_BASE',
+  'OPENAI_MODEL',
+  'NVIDIA_NIM',
+  'MINIMAX_API_KEY',
+  'USER_TYPE',
+]
+
+const originalEnv: Record<string, string | undefined> = {}
+
+beforeEach(() => {
+  for (const key of ENV_KEYS) {
+    originalEnv[key] = process.env[key]
+    delete process.env[key]
+  }
+})
+
+afterEach(() => {
+  for (const key of ENV_KEYS) {
+    if (originalEnv[key] === undefined) {
+      delete process.env[key]
+    } else {
+      process.env[key] = originalEnv[key]
+    }
+  }
+})
+
+describe('modelSupportsThinking — Z.AI GLM', () => {
+  test('enables thinking for exact GLM models on api.z.ai', () => {
+    process.env.CLAUDE_CODE_USE_OPENAI = '1'
+    process.env.OPENAI_BASE_URL = 'https://api.z.ai/api/coding/paas/v4'
+
+    expect(modelSupportsThinking('GLM-5.1')).toBe(true)
+    expect(modelSupportsThinking('GLM-5-Turbo')).toBe(true)
+    expect(modelSupportsThinking('GLM-4.7')).toBe(true)
+    expect(modelSupportsThinking('GLM-4.5-Air')).toBe(true)
+  })
+
+  test('does not enable GLM thinking on non-Z.AI OpenAI-compatible endpoints', () => {
+    process.env.CLAUDE_CODE_USE_OPENAI = '1'
+    process.env.OPENAI_BASE_URL = 'https://dashscope.aliyuncs.com/compatible-mode/v1'
+
+    expect(modelSupportsThinking('glm-5.1')).toBe(false)
+    expect(modelSupportsThinking('GLM-5.1')).toBe(false)
+  })
+
+  test('does not match unrelated GLM-looking model names', () => {
+    process.env.CLAUDE_CODE_USE_OPENAI = '1'
+    process.env.OPENAI_BASE_URL = 'https://api.z.ai/api/coding/paas/v4'
+
+    expect(modelSupportsThinking('glm-50')).toBe(false)
+  })
+})

src/utils/thinking.ts

@@ -6,6 +6,7 @@ import { getCanonicalName } from './model/model.js'
 import { get3PModelCapabilityOverride } from './model/modelSupportOverrides.js'
 import { getAPIProvider } from './model/providers.js'
 import { getSettingsWithErrors } from './settings/settings.js'
+import { isZaiBaseUrl, isZaiGlmModel } from './zaiProvider.js'
 
 export type ThinkingConfig =
   | { type: 'adaptive' }
@@ -111,6 +112,13 @@ export function modelSupportsThinking(model: string): boolean {
   ) {
     return true
   }
+  if (
+    provider === 'openai' &&
+    isZaiBaseUrl(process.env.OPENAI_BASE_URL ?? process.env.OPENAI_API_BASE) &&
+    isZaiGlmModel(canonical)
+  ) {
+    return true
+  }
   // 3P (Bedrock/Vertex): only Opus 4+ and Sonnet 4+
   return canonical.includes('sonnet-4') || canonical.includes('opus-4')
 }

src/utils/zaiProvider.ts

@@ -0,0 +1,34 @@
+const ZAI_API_HOSTS = new Set([
+  'api.z.ai',
+])
+
+const ZAI_GLM_MODEL_IDS = new Set([
+  'GLM-5.1',
+  'GLM-5-Turbo',
+  'GLM-5',
+  'GLM-4.7',
+  'GLM-4.5-Air',
+])
+
+const ZAI_GLM_MODEL_IDS_LOWER = new Set(
+  [...ZAI_GLM_MODEL_IDS].map(model => model.toLowerCase()),
+)
+
+export function isZaiBaseUrl(baseUrl: string | undefined): boolean {
+  if (!baseUrl) return false
+  try {
+    return ZAI_API_HOSTS.has(new URL(baseUrl).hostname.toLowerCase())
+  } catch {
+    return false
+  }
+}
+
+export function isZaiGlmModel(model: string): boolean {
+  return ZAI_GLM_MODEL_IDS_LOWER.has(model.trim().toLowerCase())
+}
+
+export function containsExactZaiGlmModelId(model: string): boolean {
+  return model
+    .split(',')
+    .some(entry => ZAI_GLM_MODEL_IDS.has(entry.trim()))
+}