fix: Make default optional with a disabled config default

packages/ai-providers/server-ai-openai/README.md

@@ -31,7 +31,7 @@ async def main():
     ai_config = ai_client.config(
         "my-ai-config-key",
         context,
-        default_value
+        default
     )
 
     # Create an OpenAI provider from the config

packages/sdk/server-ai/README.md

@@ -145,7 +145,7 @@ from ldai.providers.types import LDAIMetrics, TokenUsage
 from ldai_langchain import LangChainProvider
 
 async def main():
-    ai_config = ai_client.completion_config(ai_config_key, context, default_value)
+    ai_config = ai_client.completion_config(ai_config_key, context, default)
 
     # Create LangChain model from configuration
     llm = await LangChainProvider.create_langchain_model(ai_config)
@@ -169,7 +169,7 @@ from ldai import LDAIClient, AICompletionConfigDefault, ModelConfig
 from ldai.providers.types import LDAIMetrics, TokenUsage
 
 async def main():
-    ai_config = ai_client.completion_config(ai_config_key, context, default_value)
+    ai_config = ai_client.completion_config(ai_config_key, context, default)
 
     # Define custom metrics mapping for your provider
     def map_custom_provider_metrics(response):

packages/sdk/server-ai/src/ldai/client.py

@@ -49,11 +49,11 @@ def _completion_config(
         self,
         key: str,
         context: Context,
-        default_value: AICompletionConfigDefault,
+        default: AICompletionConfigDefault,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AICompletionConfig:
         model, provider, messages, instructions, tracker, enabled, judge_configuration, _ = self.__evaluate(
-            key, context, default_value.to_dict(), variables
+            key, context, default.to_dict(), variables
         )
 
         config = AICompletionConfig(
@@ -72,27 +72,30 @@ def completion_config(
         self,
         key: str,
         context: Context,
-        default_value: AICompletionConfigDefault,
+        default: Optional[AICompletionConfigDefault] = None,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AICompletionConfig:
         """
         Get the value of a completion configuration.
 
         :param key: The key of the completion configuration.
         :param context: The context to evaluate the completion configuration in.
-        :param default_value: The default value of the completion configuration.
+        :param default: The default value of the completion configuration. When not provided,
+            a disabled config is used as the fallback.
         :param variables: Additional variables for the completion configuration.
         :return: The completion configuration with a tracker used for gathering metrics.
         """
         self._client.track(_TRACK_USAGE_COMPLETION_CONFIG, context, key, 1)
 
-        return self._completion_config(key, context, default_value, variables)
+        return self._completion_config(
+            key, context, default or AICompletionConfigDefault.disabled(), variables
+        )
 
     def config(
         self,
         key: str,
         context: Context,
-        default_value: AICompletionConfigDefault,
+        default: Optional[AICompletionConfigDefault] = None,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AICompletionConfig:
         """
@@ -102,21 +105,21 @@ def config(
 
         :param key: The key of the model configuration.
         :param context: The context to evaluate the model configuration in.
-        :param default_value: The default value of the model configuration.
+        :param default: The default value of the model configuration.
         :param variables: Additional variables for the model configuration.
         :return: The value of the model configuration along with a tracker used for gathering metrics.
         """
-        return self.completion_config(key, context, default_value, variables)
+        return self.completion_config(key, context, default, variables)
 
     def _judge_config(
         self,
         key: str,
         context: Context,
-        default_value: AIJudgeConfigDefault,
+        default: AIJudgeConfigDefault,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AIJudgeConfig:
         model, provider, messages, instructions, tracker, enabled, judge_configuration, variation = self.__evaluate(
-            key, context, default_value.to_dict(), variables
+            key, context, default.to_dict(), variables
         )
 
         def _extract_evaluation_metric_key(variation: Dict[str, Any]) -> Optional[str]:
@@ -152,27 +155,30 @@ def judge_config(
         self,
         key: str,
         context: Context,
-        default_value: AIJudgeConfigDefault,
+        default: Optional[AIJudgeConfigDefault] = None,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AIJudgeConfig:
         """
         Get the value of a judge configuration.
 
         :param key: The key of the judge configuration.
         :param context: The context to evaluate the judge configuration in.
-        :param default_value: The default value of the judge configuration.
+        :param default: The default value of the judge configuration. When not provided,
+            a disabled config is used as the fallback.
         :param variables: Additional variables for the judge configuration.
         :return: The judge configuration with a tracker used for gathering metrics.
         """
         self._client.track(_TRACK_USAGE_JUDGE_CONFIG, context, key, 1)
 
-        return self._judge_config(key, context, default_value, variables)
+        return self._judge_config(
+            key, context, default or AIJudgeConfigDefault.disabled(), variables
+        )
 
     async def create_judge(
         self,
         key: str,
         context: Context,
-        default_value: AIJudgeConfigDefault,
+        default: Optional[AIJudgeConfigDefault] = None,
         variables: Optional[Dict[str, Any]] = None,
         default_ai_provider: Optional[str] = None,
     ) -> Optional[Judge]:
@@ -181,7 +187,7 @@ async def create_judge(
 
         :param key: The key identifying the AI judge configuration to use
         :param context: Standard Context used when evaluating flags
-        :param default_value: A default value representing a standard AI config result
+        :param default: A default value representing a standard AI config result
         :param variables: Dictionary of values for instruction interpolation.
             The variables `message_history` and `response_to_evaluate` are reserved for the judge and will be ignored.
         :param default_ai_provider: Optional default AI provider to use.
@@ -222,7 +228,9 @@ async def create_judge(
             extended_variables['message_history'] = '{{message_history}}'
             extended_variables['response_to_evaluate'] = '{{response_to_evaluate}}'
 
-            judge_config = self._judge_config(key, context, default_value, extended_variables)
+            judge_config = self._judge_config(
+                key, context, default or AIJudgeConfigDefault.disabled(), extended_variables
+            )
 
             if not judge_config.enabled or not judge_config.tracker:
                 return None
@@ -284,7 +292,7 @@ async def create_chat(
         self,
         key: str,
         context: Context,
-        default_value: AICompletionConfigDefault,
+        default: AICompletionConfigDefault,
         variables: Optional[Dict[str, Any]] = None,
         default_ai_provider: Optional[str] = None,
     ) -> Optional[Chat]:
@@ -293,7 +301,7 @@ async def create_chat(
 
         :param key: The key identifying the AI completion configuration to use
         :param context: Standard Context used when evaluating flags
-        :param default_value: A default value representing a standard AI config result
+        :param default: A default value representing a standard AI config result
         :param variables: Dictionary of values for instruction interpolation
         :param default_ai_provider: Optional default AI provider to use
         :return: Chat instance or None if disabled/unsupported
@@ -322,7 +330,7 @@ async def create_chat(
         """
         self._client.track(_TRACK_USAGE_CREATE_CHAT, context, key, 1)
         log.debug(f"Creating chat for key: {key}")
-        config = self._completion_config(key, context, default_value, variables)
+        config = self._completion_config(key, context, default, variables)
 
         if not config.enabled or not config.tracker:
             return None
@@ -346,7 +354,7 @@ def agent_config(
         self,
         key: str,
         context: Context,
-        default_value: AIAgentConfigDefault,
+        default: Optional[AIAgentConfigDefault] = None,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AIAgentConfig:
         """
@@ -374,7 +382,8 @@ def agent_config(
 
         :param key: The agent configuration key.
         :param context: The context to evaluate the agent configuration in.
-        :param default_value: Default agent values.
+        :param default: Default agent values. When not provided, a disabled config is used
+            as the fallback.
         :param variables: Variables for interpolation.
         :return: Configured AIAgentConfig instance.
         """
@@ -385,7 +394,9 @@ def agent_config(
             1
         )
 
-        return self.__evaluate_agent(key, context, default_value, variables)
+        return self.__evaluate_agent(
+            key, context, default or AIAgentConfigDefault.disabled(), variables
+        )
 
     def agent(
         self,
@@ -401,7 +412,7 @@ def agent(
         :param context: The context to evaluate the agent configuration in.
         :return: Configured AIAgentConfig instance.
         """
-        return self.agent_config(config.key, context, config.default_value, config.variables)
+        return self.agent_config(config.key, context, config.default, config.variables)
 
     def agent_configs(
         self,
@@ -420,15 +431,15 @@ def agent_configs(
             agents = client.agent_configs([
                 AIAgentConfigRequest(
                     key='research_agent',
-                    default_value=AIAgentConfigDefault(
+                    default=AIAgentConfigDefault(
                         enabled=True,
                         instructions='You are a research assistant.'
                     ),
                     variables={'topic': 'climate change'}
                 ),
                 AIAgentConfigRequest(
                     key='writing_agent',
-                    default_value=AIAgentConfigDefault(
+                    default=AIAgentConfigDefault(
                         enabled=True,
                         instructions='You are a writing assistant.'
                     ),
@@ -457,7 +468,7 @@ def agent_configs(
             agent = self.__evaluate_agent(
                 config.key,
                 context,
-                config.default_value,
+                config.default or AIAgentConfigDefault.disabled(),
                 config.variables
             )
             result[config.key] = agent
@@ -682,33 +693,33 @@ def __evaluate_agent(
         self,
         key: str,
         context: Context,
-        default_value: AIAgentConfigDefault,
+        default: AIAgentConfigDefault,
         variables: Optional[Dict[str, Any]] = None,
     ) -> AIAgentConfig:
         """
         Internal method to evaluate an agent configuration.
 
         :param key: The agent configuration key.
         :param context: The evaluation context.
-        :param default_value: Default agent values.
+        :param default: Default agent values.
         :param variables: Variables for interpolation.
         :return: Configured AIAgentConfig instance.
         """
         model, provider, messages, instructions, tracker, enabled, judge_configuration, _ = self.__evaluate(
-            key, context, default_value.to_dict(), variables
+            key, context, default.to_dict(), variables
         )
 
         # For agents, prioritize instructions over messages
-        final_instructions = instructions if instructions is not None else default_value.instructions
+        final_instructions = instructions if instructions is not None else default.instructions
 
         return AIAgentConfig(
             key=key,
-            enabled=bool(enabled) if enabled is not None else (default_value.enabled or False),
-            model=model or default_value.model,
-            provider=provider or default_value.provider,
+            enabled=bool(enabled) if enabled is not None else (default.enabled or False),
+            model=model or default.model,
+            provider=provider or default.provider,
             instructions=final_instructions,
             tracker=tracker,
-            judge_configuration=judge_configuration or default_value.judge_configuration,
+            judge_configuration=judge_configuration or default.judge_configuration,
         )
 
     def __interpolate_template(self, template: str, variables: Dict[str, Any]) -> str:

packages/sdk/server-ai/src/ldai/models.py

@@ -152,6 +152,14 @@ class AIConfigDefault:
     model: Optional[ModelConfig] = None
     provider: Optional[ProviderConfig] = None
 
+    @classmethod
+    def disabled(cls):
+        """
+        Returns a new disabled config default with enabled set to false.
+        When called on a subclass, returns an instance of that subclass.
+        """
+        return cls(enabled=False)
+
     def _base_to_dict(self) -> Dict[str, Any]:
         """
         Render the base config fields as a dictionary object.
@@ -334,7 +342,7 @@ class AIAgentConfigRequest:
     Combines agent key with its specific default configuration and variables.
     """
     key: str
-    default_value: AIAgentConfigDefault
+    default: Optional[AIAgentConfigDefault] = None
     variables: Optional[Dict[str, Any]] = None