Adding the Kit interface [https://github.com/tmc/langchaingo/issues/1103]

tools/tool.go

@@ -1,10 +1,26 @@
 package tools
 
-import "context"
+import (
+	"context"
+	"errors"
+)
+
+const ErrInvalidTool = "invalid_tool"
 
 // Tool is a tool for the llm agent to interact with different applications.
 type Tool interface {
 	Name() string
 	Description() string
 	Call(ctx context.Context, input string) (string, error)
 }
+
+type Kit []Tool
+
+func (tb *Kit) UseTool(ctx context.Context, toolName string, toolArgs string) (string, error) {
+	for _, tool := range *tb {
+		if tool.Name() == toolName {
+			return tool.Call(ctx, toolArgs)
+		}
+	}
+	return "", errors.New(ErrInvalidTool)
+}

tools/tool_test.go

@@ -0,0 +1,48 @@
+package tools
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type someTool struct{}
+
+func (st *someTool) Name() string {
+	return "An awesome tool"
+}
+
+func (st *someTool) Description() string {
+	return "This tool is awesome"
+}
+
+func (st *someTool) Call(ctx context.Context, _ string) (string, error) {
+	if ctx.Err() != nil {
+		return "", ctx.Err()
+	}
+	return "test", nil
+}
+
+func TestToolWithTestify(t *testing.T) {
+	t.Parallel()
+	kit := Kit{
+		&someTool{},
+	}
+
+	// Test when the tool exists
+	t.Run("Tool Exists in Kit", func(t *testing.T) {
+		t.Parallel()
+		result, err := kit.UseTool(context.Background(), "An awesome tool", "test")
+		assert.NoError(t, err)
+		assert.Equal(t, "test", result)
+	})
+
+	// Test when the tool does not exist
+	t.Run("Tool Does Not Exist in Kit", func(t *testing.T) {
+		t.Parallel()
+		_, err := kit.UseTool(context.Background(), "A tool that does not exist", "test")
+		assert.Error(t, err)
+		assert.Equal(t, ErrInvalidTool, err.Error())
+	})
+}