larksuite/cli · error

%s must contain at least %d characters

Error message

%s must contain at least %d characters

What it means

A string-shape field with a MinLength constraint received a string shorter (in runes) than the declared minimum; validation fails with the required count in the message. Thrown by validateJSONValueAgainstShape in the typedStringShape branch after the type check.

Source

Thrown at shortcuts/common/typed_binder.go:420

		if err != nil {
			return fmt.Errorf("%s has invalid const: %w", path, err)
		}
		expected, err := decodeJSONValidationValue(expectedJSON)
		if err != nil {
			return fmt.Errorf("%s has invalid const: %w", path, err)
		}
		if !reflect.DeepEqual(value, expected) {
			return fmt.Errorf("%s must equal %v", path, constraint.Value)
		}
		return nil
	case typedStringShape:
		text, ok := value.(string)
		if !ok {
			return fmt.Errorf("%s must be a string", path)
		}
		length := len([]rune(text))
		if constraint.MinLength != nil && length < *constraint.MinLength {
			return fmt.Errorf("%s must contain at least %d characters", path, *constraint.MinLength)
		}
		if constraint.MaxLength != nil && length > *constraint.MaxLength {
			return fmt.Errorf("%s must contain at most %d characters", path, *constraint.MaxLength)
		}
		if len(constraint.Enum) > 0 && !slices.Contains(constraint.Enum, text) {
			return fmt.Errorf("%s must be one of: %s", path, strings.Join(constraint.Enum, ", "))
		}
		return nil
	case typedBooleanShape:
		boolean, ok := value.(bool)
		if !ok {
			return fmt.Errorf("%s must be a boolean", path)
		}
		if len(constraint.Enum) > 0 && !slices.Contains(constraint.Enum, boolean) {
			return fmt.Errorf("%s has an unsupported boolean value", path)
		}
		return nil
	case typedIntegerShape:

View on GitHub (pinned to 7fd6ef3c07)

Solutions

  1. Supply a string at least as long as the declared minimum shown in the error.
  2. Omit the field if it is optional and you have no value.
  3. Check the config/env source — an unset variable often yields an empty string default.
  4. If the schema's minimum is wrong, update the MinLength constraint.

Example fix

// before
name := os.Getenv("DOC_NAME") // "" when unset
params.Set("name", name)      // min 1

// after
name := os.Getenv("DOC_NAME")
if name == "" { return errors.New("DOC_NAME is required") }
params.Set("name", name)
Defensive patterns

Strategy: validation

Validate before calling

if utf8.RuneCountInString(s) < minLen { return fmt.Errorf("needs at least %d characters", minLen) }

Type guard

func meetsMinLength(s string, min int) bool { return utf8.RuneCountInString(s) >= min }

Try / catch

if err := binder.Set("name", s); err != nil {
    re := regexp.MustCompile(`must contain at least (\d+)`)
    if m := re.FindStringSubmatch(err.Error()); m != nil {
        return fmt.Errorf("name needs at least %s characters (got %d)", m[1], utf8.RuneCountInString(s))
    }
    return err
}

Prevention

When it happens

Trigger: Passing an empty or too-short string to a constrained field — e.g. name: "" where min is 1, or a 3-char token where min is 8. Length is measured in runes, so multibyte characters count individually.

Common situations: Empty-string defaults from unset config variables; truncated user input; developers sending "-" or " " placeholders to satisfy required fields when MinLength > 1.

Related errors

AI-assisted analysis of larksuite/cli@7fd6ef3c07 (2026-09-04). Data as JSON: /api/errors/dcdf8453c2512035. Report an issue: GitHub.