diff --git a/internal/agent/agent.go b/internal/agent/agent.go
index 11a87f58554729048cd7a0629979a0c6bb3babd2..c7c96cd42cfce58eab918e9ae2e267ac3f78ad8d 100644
--- a/internal/agent/agent.go
+++ b/internal/agent/agent.go
@@ -364,7 +364,9 @@ func (a *sessionAgent) Run(ctx context.Context, call SessionAgentCall) (*fantasy
 				Finished:         false,
 			}
 			currentAssistant.AddToolCall(toolCall)
-			return a.messages.Update(genCtx, *currentAssistant)
+			// Use parent ctx instead of genCtx to ensure the update succeeds
+			// even if the request is canceled mid-stream
+			return a.messages.Update(ctx, *currentAssistant)
 		},
 		OnRetry: func(err *fantasy.ProviderError, delay time.Duration) {
 			// TODO: implement
@@ -378,11 +380,15 @@ func (a *sessionAgent) Run(ctx context.Context, call SessionAgentCall) (*fantasy
 				Finished:         true,
 			}
 			currentAssistant.AddToolCall(toolCall)
-			return a.messages.Update(genCtx, *currentAssistant)
+			// Use parent ctx instead of genCtx to ensure the update succeeds
+			// even if the request is canceled mid-stream
+			return a.messages.Update(ctx, *currentAssistant)
 		},
 		OnToolResult: func(result fantasy.ToolResultContent) error {
 			toolResult := a.convertToToolResult(result)
-			_, createMsgErr := a.messages.Create(genCtx, currentAssistant.SessionID, message.CreateMessageParams{
+			// Use parent ctx instead of genCtx to ensure the message is created
+			// even if the request is canceled mid-stream
+			_, createMsgErr := a.messages.Create(ctx, currentAssistant.SessionID, message.CreateMessageParams{
 				Role: message.Tool,
 				Parts: []message.ContentPart{
 					toolResult,
@@ -485,7 +491,7 @@ func (a *sessionAgent) Run(ctx context.Context, call SessionAgentCall) (*fantasy
 			}
 			content := "There was an error while executing the tool"
 			if isCancelErr {
-				content = "Tool execution canceled by user"
+				content = "Error: user cancelled assistant tool calling"
 			} else if isPermissionErr {
 				content = "User denied permission"
 			}