From 5278727c51b07e58c823c939a01a1e12ddb914ed Mon Sep 17 00:00:00 2001
From: John Costa <johncosta027@gmail.com>
Date: Sat, 5 Apr 2025 14:58:38 +0100
Subject: [PATCH] feat(tools): return error to agent if any happened

---
 backend/agents/client/tools.go      | 14 +++---
 backend/agents/client/tools_test.go | 69 ++++++++++++++++++++++++++---
 2 files changed, 71 insertions(+), 12 deletions(-)

diff --git a/backend/agents/client/tools.go b/backend/agents/client/tools.go
index 0e259ec..193fe92 100644
--- a/backend/agents/client/tools.go
+++ b/backend/agents/client/tools.go
@@ -39,16 +39,20 @@ func (handler ToolsHandlers) Handle(info ToolHandlerInfo, toolCallMessage AgentA
 		}
 
 		res, err := fnHandler.Fn(info, arguments, toolCallMessage.ToolCalls[0])
-		if err != nil {
-			return []AgentTextMessage{}, err
-		}
 
-		responses[i] = AgentTextMessage{
+		responseMessage := AgentTextMessage{
 			Role:       "tool",
 			Name:       fnName,
-			Content:    res,
 			ToolCallId: toolCall.Id,
 		}
+
+		if err != nil {
+			responseMessage.Content = err.Error()
+		} else {
+			responseMessage.Content = res
+		}
+
+		responses[i] = responseMessage
 	}
 
 	return responses, nil
diff --git a/backend/agents/client/tools_test.go b/backend/agents/client/tools_test.go
index 35423ff..cb07ece 100644
--- a/backend/agents/client/tools_test.go
+++ b/backend/agents/client/tools_test.go
@@ -1,6 +1,7 @@
 package client
 
 import (
+	"errors"
 	"testing"
 
 	"github.com/google/uuid"
@@ -19,7 +20,11 @@ func (suite *ToolTestSuite) SetupTest() {
 	}
 
 	suite.handler.AddTool("a", func(info ToolHandlerInfo, args string, call ToolCall) (any, error) {
-		return true, nil
+		return args, nil
+	})
+
+	suite.handler.AddTool("error", func(info ToolHandlerInfo, args string, call ToolCall) (any, error) {
+		return false, errors.New("I will always error")
 	})
 }
 
@@ -40,7 +45,7 @@ func (suite *ToolTestSuite) TestSingleToolCall() {
 				Id:    "1",
 				Function: FunctionCall{
 					Name:      "a",
-					Arguments: "",
+					Arguments: "return",
 				},
 			}},
 		})
@@ -49,7 +54,7 @@ func (suite *ToolTestSuite) TestSingleToolCall() {
 
 	assert.EqualValues(response, []AgentTextMessage{{
 		Role:       "tool",
-		Content:    "true",
+		Content:    "\"return\"",
 		ToolCallId: "1",
 		Name:       "a",
 	}})
@@ -90,7 +95,7 @@ func (suite *ToolTestSuite) TestMultipleToolCalls() {
 					Id:    "1",
 					Function: FunctionCall{
 						Name:      "a",
-						Arguments: "",
+						Arguments: "first-call",
 					},
 				},
 				{
@@ -98,7 +103,7 @@ func (suite *ToolTestSuite) TestMultipleToolCalls() {
 					Id:    "2",
 					Function: FunctionCall{
 						Name:      "a",
-						Arguments: "",
+						Arguments: "second-call",
 					},
 				},
 			},
@@ -109,13 +114,63 @@ func (suite *ToolTestSuite) TestMultipleToolCalls() {
 	assert.EqualValues(response, []AgentTextMessage{
 		{
 			Role:       "tool",
-			Content:    "true",
+			Content:    "\"first-call\"",
 			ToolCallId: "1",
 			Name:       "a",
 		},
 		{
 			Role:       "tool",
-			Content:    "true",
+			Content:    "\"second-call\"",
+			ToolCallId: "2",
+			Name:       "a",
+		},
+	})
+}
+
+func (suite *ToolTestSuite) TestMultipleToolCallsWithErrors() {
+	assert := suite.Assert()
+	require := suite.Require()
+
+	response, err := suite.handler.Handle(
+		ToolHandlerInfo{
+			UserId:  uuid.Nil,
+			ImageId: uuid.Nil,
+		},
+		AgentAssistantToolCall{
+			Role:    "assistant",
+			Content: "",
+			ToolCalls: []ToolCall{
+				{
+					Index: 0,
+					Id:    "1",
+					Function: FunctionCall{
+						Name:      "error",
+						Arguments: "",
+					},
+				},
+				{
+					Index: 1,
+					Id:    "2",
+					Function: FunctionCall{
+						Name:      "a",
+						Arguments: "no-error",
+					},
+				},
+			},
+		})
+
+	require.NoError(err, "Tool call shouldnt return an error")
+
+	assert.EqualValues(response, []AgentTextMessage{
+		{
+			Role:       "tool",
+			Content:    "I will always error",
+			ToolCallId: "1",
+			Name:       "error",
+		},
+		{
+			Role:       "tool",
+			Content:    "\"no-error\"",
 			ToolCallId: "2",
 			Name:       "a",
 		},