Add list files tool

main.go

@@ -6,6 +6,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
+	"path/filepath"
+	"strings"
 
 	"github.com/anthropics/anthropic-sdk-go"
 	"github.com/invopop/jsonschema"
@@ -21,7 +23,7 @@ func main() {
 		}
 		return scanner.Text(), true
 	}
-	tools := []ToolDefinition{ReadFileDefinition}
+	tools := []ToolDefinition{ReadFileDefinition, ListFilesDefinition}
 
 	agent := NewAgent(&client, getUserMessage, tools)
 	err := agent.Run(context.TODO())
@@ -179,3 +181,67 @@ func GenerateSchema[T any]() anthropic.ToolInputSchemaParam {
 		Properties: schema.Properties,
 	}
 }
+
+var ListFilesDefinition = ToolDefinition{
+	Name:        "list_files",
+	Description: "List files and directories at a given path. If no path is provided, lists files in the current directory.",
+	InputSchema: ListFilesInputSchema,
+	Function:    ListFiles,
+}
+
+type ListFilesInput struct {
+	Path string `json:"path,omitempty" jsonschema_description:"Optional relative path to list files from. Defaults to current directory if not provided."`
+}
+
+var ListFilesInputSchema = GenerateSchema[ListFilesInput]()
+
+func ListFiles(input json.RawMessage) (string, error) {
+	listFilesInput := ListFilesInput{}
+	err := json.Unmarshal(input, &listFilesInput)
+	if err != nil {
+		panic(err)
+	}
+
+	dir := "."
+	if listFilesInput.Path != "" {
+		dir = listFilesInput.Path
+	}
+
+	var files []string
+	err = filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		// Ignore devenv folder because it blows up the list of files (too many
+		// tokens)
+		if strings.Contains(path, ".devenv") {
+			return nil
+		}
+
+		relPath, err := filepath.Rel(dir, path)
+		if err != nil {
+			return err
+		}
+
+		if relPath != "." {
+			if info.IsDir() {
+				files = append(files, relPath+"/")
+			} else {
+				files = append(files, relPath)
+			}
+		}
+		return nil
+	})
+
+	if err != nil {
+		return "", err
+	}
+
+	result, err := json.Marshal(files)
+	if err != nil {
+		return "", err
+	}
+
+	return string(result), nil
+}