larksuite/cli · error

required input cannot declare default

Error message

required input cannot declare default

What it means

A field marked `required` in its schema tag cannot also declare a `default` value. A required input must always be supplied by the caller, so a default would be unreachable and signals a contradiction; parseSchemaTag rejects this combination at compile time.

Source

Thrown at shortcuts/common/typed_compile_args.go:498

			if err != nil {
				return result, fmt.Errorf("schema minItems: %w", err)
			}
			result.minItems = &v
		case "maxItems":
			v, err := parseNonnegativeInt(value)
			if err != nil {
				return result, fmt.Errorf("schema maxItems: %w", err)
			}
			result.maxItems = &v
		default:
			return result, fmt.Errorf("unknown schema token %q", key)
		}
	}
	if result.required == result.optional {
		return result, fmt.Errorf("schema must declare exactly one of required or optional")
	}
	if result.required && result.defaultValue.Set {
		return result, fmt.Errorf("required input cannot declare default")
	}
	if result.nullable != nil && *result.nullable && !isNilCapable(valueType) {
		return result, fmt.Errorf("nullable requires a nil-capable Go type")
	}
	if result.minLength != nil && result.maxLength != nil && *result.minLength > *result.maxLength {
		return result, fmt.Errorf("minLength exceeds maxLength")
	}
	if result.minimum != nil && result.maximum != nil && *result.minimum > *result.maximum {
		return result, fmt.Errorf("minimum exceeds maximum")
	}
	if result.minItems != nil && result.maxItems != nil && *result.minItems > *result.maxItems {
		return result, fmt.Errorf("minItems exceeds maxItems")
	}
	return result, nil
}

func parseCLITag(raw string) (typedCLIInput, error) {
	var result typedCLIInput

View on GitHub (pinned to 7fd6ef3c07)

Solutions

1. If callers may omit the field, change required to optional and keep the default.
2. If the field must be provided, remove the default token.
3. Review the field's intent: a default implies optionality.

Example fix

// before
Locale string `schema:"required;default=\"en-US\""`
// after
Locale string `schema:"optional;default=\"en-US\""`

func requiredHasNoDefault(tag string) bool {
	required, hasDefault := false, false
	for _, tok := range strings.Split(tag, ";") {
		if k, _, _ := strings.Cut(tok, "="); k == "required" {
			required = true
		}
		if strings.HasPrefix(tok, "default=") {
			hasDefault = true
		}
	}
	return !(required && hasDefault)
}

When it happens

Trigger: A tag like schema:"required;default=\"x\"" on an input struct field compiled via collectArgFields.

Common situations: Changing a field from optional to required while leaving its default in place, or adding required to a field that was designed with a fallback value.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• schema minItems: %w
• schema maxItems: %w
• unknown schema token %q
• schema must declare exactly one of required or optional
• nullable requires a nil-capable Go type

AI-assisted analysis of larksuite/cli@7fd6ef3c07 (2026-09-04). Data as JSON: /api/errors/8ff22fad71673b93. Report an issue: GitHub.