Adjust read_file so it returns line numbers

pkg/cli/functions.go

@@ -79,12 +79,15 @@ For directories, size represents the number of entries in that directory.`,
 	"read_file": {
 		Tool: openai.Tool{Type: "function", Function: openai.FunctionDefinition{
 			Name: "read_file",
-			Description: `Read the contents of a file relative to the current working directory.
+			Description: `Read the contents of a text file relative to the current working directory.
 
-Result is returned as JSON in the following format:
+Each line of the file is prefixed with its line number and a tabs (\t) to make
+it make it easier to see which lines to change for other modifications.
+
+Example:
 {
 	"message": "success", // if successful, or a different message indicating failure
-	"result": "the contents\nof the file\n"
+	"result": "1\tthe contents\n2\tof the file\n"
 }`,
 			Parameters: FunctionParameters{
 				Type: "object",
@@ -327,8 +330,15 @@ func ReadFile(path string) string {
 	if err != nil {
 		return resultToJson(FunctionResult{Message: fmt.Sprintf("Could not read path: %s", err.Error())})
 	}
+
+	lines := strings.Split(string(data), "\n")
+	content := strings.Builder{}
+	for i, line := range lines {
+		content.WriteString(fmt.Sprintf("%d\t%s\n", i+1, line))
+	}
+
 	return resultToJson(FunctionResult{
-		Result: string(data),
+		Result: content.String(),
 	})
 }