feat: add Azure Anthropic (Claude) provider support

- Add "Azure Anthropic (Claude)" to API_PROVIDERS in registry.py
  with ANTHROPIC_API_KEY auth (required for Claude CLI to route
  through custom base URL instead of default Anthropic endpoint)
- Add Azure env var template to .env.example
- Show Base URL input field for Azure provider in Settings UI
  with "Configured" state and Azure-specific placeholder
- Widen Settings modal for better readability with long URLs
- Add Azure endpoint detection and "Azure Mode" log label
- Rename misleading "GLM Mode" fallback label to "Alternative API"

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.env.example

@@ -30,11 +30,18 @@
 # ANTHROPIC_DEFAULT_HAIKU_MODEL=claude-3-5-haiku@20241022
 
 # ===================
-# Alternative API Providers (GLM, Ollama, Kimi, Custom)
+# Alternative API Providers (Azure, GLM, Ollama, Kimi, Custom)
 # ===================
 # Configure via Settings UI (recommended) or set env vars below.
 # When both are set, env vars take precedence.
 #
+# Azure Anthropic (Claude):
+# ANTHROPIC_BASE_URL=https://your-resource.services.ai.azure.com/anthropic
+# ANTHROPIC_API_KEY=your-azure-api-key
+# ANTHROPIC_DEFAULT_OPUS_MODEL=claude-opus-4-6
+# ANTHROPIC_DEFAULT_SONNET_MODEL=claude-sonnet-4-5
+# ANTHROPIC_DEFAULT_HAIKU_MODEL=claude-haiku-4-5
+#
 # GLM (Zhipu AI):
 # ANTHROPIC_BASE_URL=https://api.z.ai/api/anthropic
 # ANTHROPIC_AUTH_TOKEN=your-glm-api-key

client.py

@@ -463,6 +463,7 @@ def create_client(
     is_vertex = sdk_env.get("CLAUDE_CODE_USE_VERTEX") == "1"
     is_alternative_api = bool(base_url) or is_vertex
     is_ollama = "localhost:11434" in base_url or "127.0.0.1:11434" in base_url
+    is_azure = "services.ai.azure.com" in base_url
     model = convert_model_for_vertex(model)
     if sdk_env:
         print(f"   - API overrides: {', '.join(sdk_env.keys())}")
@@ -472,8 +473,10 @@ def create_client(
             print(f"   - Vertex AI Mode: Using GCP project '{project_id}' with model '{model}' in region '{region}'")
         elif is_ollama:
             print("   - Ollama Mode: Using local models")
+        elif is_azure:
+            print(f"   - Azure Mode: Using {base_url}")
         elif "ANTHROPIC_BASE_URL" in sdk_env:
-            print(f"   - GLM Mode: Using {sdk_env['ANTHROPIC_BASE_URL']}")
+            print(f"   - Alternative API: Using {sdk_env['ANTHROPIC_BASE_URL']}")
 
     # Create a wrapper for bash_security_hook that passes project_dir via context
     async def bash_hook_with_context(input_data, tool_use_id=None, context=None):

registry.py

@@ -676,6 +676,18 @@ API_PROVIDERS: dict[str, dict[str, Any]] = {
         ],
         "default_model": "glm-4.7",
     },
+    "azure": {
+        "name": "Azure Anthropic (Claude)",
+        "base_url": "",
+        "requires_auth": True,
+        "auth_env_var": "ANTHROPIC_API_KEY",
+        "models": [
+            {"id": "claude-opus-4-6", "name": "Claude Opus"},
+            {"id": "claude-sonnet-4-5", "name": "Claude Sonnet"},
+            {"id": "claude-haiku-4-5", "name": "Claude Haiku"},
+        ],
+        "default_model": "claude-opus-4-6",
+    },
     "ollama": {
         "name": "Ollama (Local)",
         "base_url": "http://localhost:11434",

ui/src/components/SettingsModal.tsx

@@ -83,8 +83,10 @@ export function SettingsModal({ isOpen, onClose }: SettingsModalProps) {
   }
 
   const handleSaveCustomBaseUrl = () => {
-    if (customBaseUrlInput.trim() && !updateSettings.isPending) {
-      updateSettings.mutate({ api_base_url: customBaseUrlInput.trim() })
+    const effectiveBaseUrl = customBaseUrlInput || settings?.api_base_url || ''
+    if (effectiveBaseUrl.trim() && !updateSettings.isPending) {
+      updateSettings.mutate({ api_base_url: effectiveBaseUrl.trim() })
+      setCustomBaseUrlInput('')
     }
   }
 
@@ -102,12 +104,12 @@ export function SettingsModal({ isOpen, onClose }: SettingsModalProps) {
   const currentProviderInfo: ProviderInfo | undefined = providers.find(p => p.id === currentProvider)
   const isAlternativeProvider = currentProvider !== 'claude'
   const showAuthField = isAlternativeProvider && currentProviderInfo?.requires_auth
-  const showBaseUrlField = currentProvider === 'custom'
+  const showBaseUrlField = currentProvider === 'custom' || currentProvider === 'azure'
   const showCustomModelInput = currentProvider === 'custom' || currentProvider === 'ollama'
 
   return (
     <Dialog open={isOpen} onOpenChange={(open) => !open && onClose()}>
-      <DialogContent aria-describedby={undefined} className="sm:max-w-sm max-h-[85vh] overflow-y-auto">
+      <DialogContent aria-describedby={undefined} className="sm:max-w-lg max-h-[90vh] overflow-y-auto">
         <DialogHeader>
           <DialogTitle className="flex items-center gap-2">
             Settings
@@ -289,22 +291,38 @@ export function SettingsModal({ isOpen, onClose }: SettingsModalProps) {
               {showBaseUrlField && (
                 <div className="space-y-2 pt-1">
                   <Label className="text-sm">Base URL</Label>
-                  <div className="flex gap-2">
-                    <input
-                      type="text"
-                      value={customBaseUrlInput || settings.api_base_url || ''}
-                      onChange={(e) => setCustomBaseUrlInput(e.target.value)}
-                      placeholder="https://api.example.com/v1"
-                      className="flex-1 py-1.5 px-3 text-sm border rounded-md bg-background"
-                    />
-                    <Button
-                      size="sm"
-                      onClick={handleSaveCustomBaseUrl}
-                      disabled={!customBaseUrlInput.trim() || isSaving}
-                    >
-                      Save
-                    </Button>
-                  </div>
+                  {settings.api_base_url && !customBaseUrlInput && (
+                    <div className="flex items-center gap-2 text-sm text-muted-foreground">
+                      <ShieldCheck size={14} className="text-green-500" />
+                      <span className="truncate">{settings.api_base_url}</span>
+                      <Button
+                        variant="ghost"
+                        size="sm"
+                        className="h-auto py-0.5 px-2 text-xs shrink-0"
+                        onClick={() => setCustomBaseUrlInput(settings.api_base_url || ' ')}
+                      >
+                        Change
+                      </Button>
+                    </div>
+                  )}
+                  {(!settings.api_base_url || customBaseUrlInput) && (
+                    <div className="flex gap-2">
+                      <input
+                        type="text"
+                        value={customBaseUrlInput.trim()}
+                        onChange={(e) => setCustomBaseUrlInput(e.target.value)}
+                        placeholder={currentProvider === 'azure' ? 'https://your-resource.services.ai.azure.com/anthropic' : 'https://api.example.com/v1'}
+                        className="flex-1 py-1.5 px-3 text-sm border rounded-md bg-background"
+                      />
+                      <Button
+                        size="sm"
+                        onClick={handleSaveCustomBaseUrl}
+                        disabled={!customBaseUrlInput.trim() || isSaving}
+                      >
+                        Save
+                      </Button>
+                    </div>
+                  )}
                 </div>
               )}
             </div>