backend/agents/client/tools.go

@@ -22,6 +22,8 @@ type ToolsHandlers struct {
 
 var NoToolCallError = errors.New("An assistant tool call with no tool calls was provided.")
 
+const NonExistantTool = "This tool does not exist"
+
 func (handler ToolsHandlers) Handle(info ToolHandlerInfo, toolCallMessage AgentAssistantToolCall) ([]AgentTextMessage, error) {
 	if len(toolCallMessage.ToolCalls) == 0 {
 		return []AgentTextMessage{}, NoToolCallError
@@ -33,19 +35,21 @@ func (handler ToolsHandlers) Handle(info ToolHandlerInfo, toolCallMessage AgentA
 		fnName := toolCall.Function.Name
 		arguments := toolCall.Function.Arguments
 
-		fnHandler, exists := handler.handlers[fnName]
-		if !exists {
-			return []AgentTextMessage{}, errors.New("Could not find tool with this name.")
-		}
-
-		res, err := fnHandler.Fn(info, arguments, toolCallMessage.ToolCalls[0])
-
 		responseMessage := AgentTextMessage{
 			Role:       "tool",
 			Name:       fnName,
 			ToolCallId: toolCall.Id,
 		}
 
+		fnHandler, exists := handler.handlers[fnName]
+		if !exists {
+			responseMessage.Content = NonExistantTool
+			responses[i] = responseMessage
+			continue
+		}
+
+		res, err := fnHandler.Fn(info, arguments, toolCallMessage.ToolCalls[0])
+
 		if err != nil {
 			responseMessage.Content = err.Error()
 		} else {

backend/agents/client/tools_test.go

@@ -151,6 +151,14 @@ func (suite *ToolTestSuite) TestMultipleToolCallsWithErrors() {
 				{
 					Index: 1,
 					Id:    "2",
+					Function: FunctionCall{
+						Name:      "non-existant",
+						Arguments: "",
+					},
+				},
+				{
+					Index: 2,
+					Id:    "3",
 					Function: FunctionCall{
 						Name:      "a",
 						Arguments: "no-error",
@@ -170,8 +178,14 @@ func (suite *ToolTestSuite) TestMultipleToolCallsWithErrors() {
 		},
 		{
 			Role:       "tool",
-			Content:    "\"no-error\"",
+			Content:    "This tool does not exist",
 			ToolCallId: "2",
+			Name:       "non-existant",
+		},
+		{
+			Role:       "tool",
+			Content:    "\"no-error\"",
+			ToolCallId: "3",
 			Name:       "a",
 		},
 	})