fix: disable system message (CopilotKit#2313)

Author: ranst91

CopilotKit/.changeset/afraid-kings-suffer.md

@@ -0,0 +1,7 @@
+---
+"@copilotkit/react-core": patch
+"@copilotkit/react-ui": patch
+---
+
+- fix: allow disabling of default cpk system message
+- chore: set up direct fastapi usage on coagents starter poetry demo

CopilotKit/packages/react-core/src/hooks/use-chat.ts

@@ -159,6 +159,8 @@ export type UseChatOptions = {
   langGraphInterruptAction: LangGraphInterruptAction | null;
 
   setLangGraphInterruptAction: LangGraphInterruptActionSetter;
+
+  disableSystemMessage?: boolean;
 };
 
 export type UseChatHelpers = {
@@ -222,6 +224,7 @@ export function useChat(options: UseChatOptions): UseChatHelpers {
     setExtensions,
     langGraphInterruptAction,
     setLangGraphInterruptAction,
+    disableSystemMessage = false,
   } = options;
   const runChatCompletionRef = useRef<(previousMessages: Message[]) => Promise<Message[]>>();
   const addErrorToast = useErrorToast();
@@ -321,9 +324,9 @@ export function useChat(options: UseChatOptions): UseChatHelpers {
 
       setMessages([...previousMessages, ...newMessages]);
 
-      const systemMessage = makeSystemMessageCallback();
-
-      const messagesWithContext = [systemMessage, ...(initialMessages || []), ...previousMessages];
+      const messagesWithContext = disableSystemMessage
+        ? [...(initialMessages || []), ...previousMessages]
+        : [makeSystemMessageCallback(), ...(initialMessages || []), ...previousMessages];
 
       // ----- Set mcpServers in properties -----
       // Create a copy of properties to avoid modifying the original object
@@ -871,6 +874,7 @@ export function useChat(options: UseChatOptions): UseChatHelpers {
       coagentStatesRef,
       agentSession,
       setAgentSession,
+      disableSystemMessage,
     ],
   );
 

CopilotKit/packages/react-core/src/hooks/use-copilot-chat_internal.ts

@@ -41,6 +41,11 @@ export interface UseCopilotChatOptions {
    * A function to generate the system message. Defaults to `defaultSystemMessage`.
    */
   makeSystemMessage?: SystemMessageFunction;
+
+  /**
+   * Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+   */
+  disableSystemMessage?: boolean;
 }
 
 export interface MCPServerConfig {
@@ -390,6 +395,7 @@ export function useCopilotChat(options: UseCopilotChatOptions = {}): UseCopilotC
     setExtensions,
     langGraphInterruptAction,
     setLangGraphInterruptAction,
+    disableSystemMessage: options.disableSystemMessage,
   });
 
   const latestAppend = useUpdatedRef(append);

CopilotKit/packages/react-ui/src/components/chat/Chat.tsx

@@ -225,6 +225,11 @@ export interface CopilotChatProps {
    */
   makeSystemMessage?: SystemMessageFunction;
 
+  /**
+   * Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+   */
+  disableSystemMessage?: boolean;
+
   /**
    * A custom assistant message component to use instead of the default.
    */
@@ -384,6 +389,7 @@ export function CopilotChat({
   suggestions = "auto",
   onSubmitMessage,
   makeSystemMessage,
+  disableSystemMessage,
   onInProgress,
   onStopGeneration,
   onReloadMessages,
@@ -584,6 +590,7 @@ export function CopilotChat({
   } = useCopilotChatLogic(
     suggestions,
     makeSystemMessage,
+    disableSystemMessage,
     onInProgress,
     onSubmitMessage,
     onStopGeneration,
@@ -789,6 +796,7 @@ export function WrappedCopilotChat({
 export const useCopilotChatLogic = (
   chatSuggestions: ChatSuggestions,
   makeSystemMessage?: SystemMessageFunction,
+  disableSystemMessage?: boolean,
   onInProgress?: (isLoading: boolean) => void,
   onSubmitMessage?: (messageContent: string) => Promise<void> | void,
   onStopGeneration?: OnStopGeneration,
@@ -809,6 +817,7 @@ export const useCopilotChatLogic = (
     isLoadingSuggestions,
   } = useCopilotChat({
     makeSystemMessage,
+    disableSystemMessage,
   });
 
   const generalContext = useCopilotContext();

docs/content/docs/reference/components/chat/CopilotChat.mdx

@@ -162,6 +162,10 @@ A function that takes in context string and instructions and returns
   instructions is not enough.
 </PropertyReference>
 
+<PropertyReference name="disableSystemMessage" type="boolean"  > 
+Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+</PropertyReference>
+
 <PropertyReference name="AssistantMessage" type="React.ComponentType<AssistantMessageProps>"  > 
 A custom assistant message component to use instead of the default.
 </PropertyReference>

docs/content/docs/reference/components/chat/CopilotPopup.mdx

@@ -166,6 +166,10 @@ A function that takes in context string and instructions and returns
   instructions is not enough.
 </PropertyReference>
 
+<PropertyReference name="disableSystemMessage" type="boolean"  > 
+Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+</PropertyReference>
+
 <PropertyReference name="AssistantMessage" type="React.ComponentType<AssistantMessageProps>"  > 
 A custom assistant message component to use instead of the default.
 </PropertyReference>

docs/content/docs/reference/components/chat/CopilotSidebar.mdx

@@ -170,6 +170,10 @@ A function that takes in context string and instructions and returns
   instructions is not enough.
 </PropertyReference>
 
+<PropertyReference name="disableSystemMessage" type="boolean"  > 
+Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+</PropertyReference>
+
 <PropertyReference name="AssistantMessage" type="React.ComponentType<AssistantMessageProps>"  > 
 A custom assistant message component to use instead of the default.
 </PropertyReference>

docs/content/docs/reference/hooks/useCopilotChat.mdx

@@ -102,3 +102,7 @@ Initial messages to populate the chat with.
 A function to generate the system message. Defaults to `defaultSystemMessage`.
 </PropertyReference>
 
+<PropertyReference name="disableSystemMessage" type="boolean"  > 
+Disables inclusion of CopilotKit’s default system message. When true, no system message is sent (this also suppresses any custom message from <code>makeSystemMessage</code>).
+</PropertyReference>
+

examples/coagents-starter/agent-py/.gitignore

@@ -3,3 +3,6 @@ __pycache__/
 *.pyc
 .env
 .vercel
+
+# LangGraph API
+.langgraph_api

examples/coagents-starter/agent-py/sample_agent/agent.py

@@ -113,10 +113,9 @@ async def chat_node(state: AgentState, config: RunnableConfig) -> Command[Litera
 
 # Conditionally use a checkpointer based on the environment
 # Check for multiple indicators that we're running in LangGraph dev/API mode
-is_langgraph_api = (
-    os.environ.get("LANGGRAPH_API", "false").lower() == "true" or
-    os.environ.get("LANGGRAPH_API_DIR") is not None
-)
+is_langgraph_api = os.environ.get("LANGGRAPH_API_DIR") is not None
+if os.environ.get("LANGGRAPH_API", None) is not None:
+    is_langgraph_api = os.environ.get("LANGGRAPH_API", None).lower() == "true"
 
 if is_langgraph_api:
     # When running in LangGraph API/dev, don't use a custom checkpointer