Streaming Behavior Improvements

Previously, during streaming conversations with tool use, users would experience a poor UX where:

• After each tool/response cycle, prior streamed messages would be hidden
• Messages would only become visible again after the entire conversation turn completed
• This created confusion during long tool execution sequences
• Interactive tools (like ask_user) would lose conversation context

File: /frontend/hooks/useAnthropicStream.tsx

• Added optional onAddMessage callback parameter to immediately add completed messages
• Modified the tool execution loop to call onAddMessage immediately after each streaming cycle completes
• Both assistant messages and tool result messages are now added to visible history immediately

Key Changes:

// Function signature updated
export default function useAnthropicStream(
  config: AppConfig, 
  clientPool: MCPClientPool, 
  affordanceManager: any,
  onAddMessage?: (message: Message) => void  // NEW: Immediate message callback
)

// Immediate message addition after streaming completes
if (onAddMessage) {
  onAddMessage({
    id: crypto.randomUUID(),
    role: message.role,
    content: message.content,
    timestamp: Date.now(),
  });
}

File: /frontend/components/StreamingChat.tsx

• Passed onAddMessage callback to the useAnthropicStream hook
• Removed duplicate message addition in fireSend and retryMessage functions since messages are now added immediately during streaming

Key Changes:

// Pass callback to streaming hook
const { status, liveBlocks, pendingTool, send, abort, resolvePendingTool, cancelPendingTool } = useAnthropicStream(
  config,
  clientPool,
  affordanceManager,
  onAddMessage, // NEW: Pass immediate message callback
);

// Removed duplicate message addition
// Messages are now added immediately during streaming via the onAddMessage callback
// No need to add them again here

File: /README.md

• Added section explaining the streaming behavior improvements
• Documented the immediate message visibility feature
• Explained how context is preserved during tool execution

• Immediate Feedback: Users see completed responses immediately, not after entire conversation turn
• Preserved Context: Previous messages remain visible throughout tool execution cycles
• Better Interactive Tools: Tools like ask_user maintain full conversation context
• Reduced Confusion: No more "disappearing messages" during long tool sequences

• Cleaner Architecture: Single source of truth for message addition
• Reduced Complexity: Eliminated duplicate message handling logic
• Better State Management: Clear separation between streaming preview and completed messages
• Maintained Performance: No additional overhead, just better timing of operations

1. User sends message
2. Assistant streams response → liveBlocks shows streaming content
3. Tool execution begins → liveBlocks remains with previous content
4. New response streams → liveBlocks replaced with new content (previous hidden)
5. Tool execution completes → All messages added to history at once

1. User sends message
2. Assistant streams response → liveBlocks shows streaming content
3. Streaming completes → Message immediately added to visible history
4. Tool execution begins → Previous message remains visible
5. Tool results → Immediately added to visible history
6. New response streams → liveBlocks only shows current streaming content
7. Each cycle → Messages immediately visible, context preserved

The implementation has been tested and verified:

• ✅ Application compiles without TypeScript errors
• ✅ Frontend loads correctly
• ✅ No runtime errors in server logs
• ✅ Streaming architecture remains intact
• ✅ Backward compatibility maintained

This improvement maintains the existing streaming architecture while providing better UX. Future enhancements could include:

• Message transition animations for newly added messages
• Visual indicators for tool execution progress
• Enhanced error handling for failed message additions