feat: Add Custom LLM Provider - Support any OpenAI-compatible API

backend_api_python/app/config/api_keys.py

@@ -99,6 +99,36 @@ def GROK_API_KEY(cls):
         from app.utils.config_loader import load_addon_config
         val = load_addon_config().get('grok', {}).get('api_key')
         return val if val else ''
+
+    @property
+    def CUSTOM_API_KEY(cls):
+        """Custom LLM API key (for OpenAI-compatible custom endpoints)"""
+        env_val = os.getenv('CUSTOM_API_KEY', '').strip()
+        if env_val:
+            return env_val
+        from app.utils.config_loader import load_addon_config
+        val = load_addon_config().get('custom', {}).get('api_key')
+        return val if val else ''
+
+    @property
+    def CUSTOM_API_URL(cls):
+        """Custom LLM API base URL (e.g., https://your-api.com/v1)"""
+        env_val = os.getenv('CUSTOM_API_URL', '').strip()
+        if env_val:
+            return env_val
+        from app.utils.config_loader import load_addon_config
+        val = load_addon_config().get('custom', {}).get('base_url')
+        return val if val else ''
+
+    @property
+    def CUSTOM_MODEL(cls):
+        """Custom LLM model name"""
+        env_val = os.getenv('CUSTOM_MODEL', '').strip()
+        if env_val:
+            return env_val
+        from app.utils.config_loader import load_addon_config
+        val = load_addon_config().get('custom', {}).get('model')
+        return val if val else ''
 
     @property
     def TAVILY_API_KEYS(cls):

backend_api_python/app/routes/settings.py

@@ -131,6 +131,7 @@ def _refresh_runtime_services() -> None:
                     {'value': 'google', 'label': 'Google Gemini'},
                     {'value': 'deepseek', 'label': 'DeepSeek'},
                     {'value': 'grok', 'label': 'xAI Grok'},
+                    {'value': 'custom', 'label': 'Custom API (OpenAI-compatible)'},
                 ],
                 'description': 'Select your preferred LLM provider'
             },
@@ -263,6 +264,31 @@ def _refresh_runtime_services() -> None:
                 'description': 'xAI Grok API endpoint',
                 'group': 'grok'
             },
+            # Custom API (OpenAI-compatible)
+            {
+                'key': 'CUSTOM_API_URL',
+                'label': 'Custom API URL',
+                'type': 'text',
+                'default': '',
+                'description': 'Your custom API endpoint (OpenAI-compatible, e.g. https://api.example.com/v1)',
+                'group': 'custom'
+            },
+            {
+                'key': 'CUSTOM_API_KEY',
+                'label': 'Custom API Key',
+                'type': 'password',
+                'required': False,
+                'description': 'API key for your custom endpoint',
+                'group': 'custom'
+            },
+            {
+                'key': 'CUSTOM_MODEL',
+                'label': 'Custom Model',
+                'type': 'text',
+                'default': '',
+                'description': 'Model name to use (e.g. gpt-4o, claude-3-opus)',
+                'group': 'custom'
+            },
             # Common settings
             {
                 'key': 'OPENROUTER_TEMPERATURE',

backend_api_python/app/services/llm.py

@@ -23,6 +23,7 @@ class LLMProvider(Enum):
     GOOGLE = "google"
     DEEPSEEK = "deepseek"
     GROK = "grok"
+    CUSTOM = "custom"
 
 
 # Provider configurations
@@ -52,6 +53,11 @@ class LLMProvider(Enum):
         "default_model": "grok-beta",
         "fallback_model": "grok-beta",
     },
+    LLMProvider.CUSTOM: {
+        "base_url": "",  # User configured via CUSTOM_API_URL
+        "default_model": "",  # User configured via CUSTOM_MODEL
+        "fallback_model": "",
+    },
 }
 
 
@@ -117,6 +123,7 @@ def get_api_key(self, provider: LLMProvider = None) -> str:
             LLMProvider.GOOGLE: APIKeys.GOOGLE_API_KEY,
             LLMProvider.DEEPSEEK: APIKeys.DEEPSEEK_API_KEY,
             LLMProvider.GROK: APIKeys.GROK_API_KEY,
+            LLMProvider.CUSTOM: APIKeys.CUSTOM_API_KEY,
         }
         return key_map.get(p, "") or ""