larksuite/cli · error

schema token %s does not accept a value

Error message

schema token %s does not accept a value

What it means

Thrown by parseSchemaTag when the nullable or nonnullable token is given a value (e.g. nullable=true). Both are mutually exclusive bare markers; a value is not accepted, and declaring both is also rejected immediately after.

Source

Thrown at shortcuts/common/typed_compile_args.go:425

		key, value, hasValue := strings.Cut(token, "=")
		if _, duplicate := seen[key]; duplicate {
			return result, fmt.Errorf("schema token %q is duplicated", key)
		}
		seen[key] = struct{}{}
		switch key {
		case "required":
			if hasValue {
				return result, fmt.Errorf("schema token required does not accept a value")
			}
			result.required = true
		case "optional":
			if hasValue {
				return result, fmt.Errorf("schema token optional does not accept a value")
			}
			result.optional = true
		case "nullable", "nonnullable":
			if hasValue {
				return result, fmt.Errorf("schema token %s does not accept a value", key)
			}
			if result.nullable != nil {
				return result, fmt.Errorf("schema cannot declare both nullable and nonnullable")
			}
			v := key == "nullable"
			result.nullable = &v
		case "default":
			if !hasValue || value == "" {
				return result, fmt.Errorf("schema default requires a JSON literal")
			}
			if !input {
				return result, fmt.Errorf("Data field cannot declare default")
			}
			var decoded any
			if err := json.Unmarshal([]byte(value), &decoded); err != nil {
				return result, fmt.Errorf("schema default is not valid JSON: %w", err)
			}
			result.defaultValue = typedInputDefault{Set: true, Value: decoded}

View on GitHub (pinned to 7fd6ef3c07)

Solutions

1. Write bare `nullable` or `nonnullable` with no value
2. Use `nonnullable` instead of `nullable=false`
3. Ensure only one of nullable/nonnullable appears in the tag

Example fix

// before
Name string `cli:"--name;schema:\"required;nullable=true\""`
// after
Name string `cli:"--name;schema:\"required;nullable\""`

if (key == "nullable" || key == "nonnullable") && strings.Contains(token, "=") {
    return fmt.Errorf("%s must be a bare token", key)
}
if strings.Contains(tag, "nullable") && strings.Contains(tag, "nonnullable") {
    return fmt.Errorf("declare only one of nullable/nonnullable")
}

When it happens

Trigger: A tag like `schema:"required;nullable=true"`; the case "nullable","nonnullable" branch checks hasValue and formats the offending key into the message.

Common situations: Applying key=value style uniformly; copying boolean attribute syntax from OpenAPI/JSON-Schema into the tag; generators emitting nullable=false for non-nullable fields.

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 token required does not accept a value
• schema token optional does not accept a value
• schema tag must declare exactly one of required or optional
• schema contains blank or untrimmed token %q
• schema token %q is duplicated

AI-assisted analysis of larksuite/cli@7fd6ef3c07 (2026-09-04). Data as JSON: /api/errors/12a130198aa0355a. Report an issue: GitHub.