cayleygraph/cayley · error

label directive should have 0 or 1 argument

Error message

label directive should have 0 or 1 argument

What it means

The @label directive controls which labels (subgraphs) are traversed, and it accepts at most one argument. Supplying two or more arguments to @label is rejected with this error.

Source

Thrown at query/graphql/graphql.go:516

	out.Labels = labels
	name := fld.Name.Value
	if fld.Alias != nil && fld.Alias.Value != "" {
		out.Alias = fld.Alias.Value
	} else {
		out.Alias = name
	}
	out.Via, out.Rev = stringToVia(name)
	// first check for "label" directive - it will affect all traversals
	for _, d := range fld.Directives {
		if d.Name == nil {
			continue
		}
		switch d.Name.Value {
		case "label":
			if len(d.Arguments) == 0 {
				out.Labels = nil
			} else if len(d.Arguments) > 1 {
				return out, fmt.Errorf("label directive should have 0 or 1 argument")
			} else if a := d.Arguments[0]; a.Name == nil || a.Name.Value != "v" {
				return out, fmt.Errorf("label directive should have 'v' argument")
			} else {
				vals, err := convValue(a.Value)
				if err != nil {
					return out, fmt.Errorf("error parsing label: %v", err)
				}
				out.Labels = vals
			}
		}
	}
	for _, d := range fld.Directives {
		if d.Name == nil {
			continue
		}
		switch d.Name.Value {
		case "rev", "reverse":
			if len(d.Arguments) == 0 {

View on GitHub (pinned to 81dcd7d73e)

Solutions

1. Use at most one argument: `@label(v: ...)`
2. Pass multiple values via a list value in the single `v` argument if supported
3. Remove extra arguments from the directive

Example fix

// before
q := "query { node @label(v: "a", rev: true) { id } }"
// after
q := "query { node @label(v: "a") { id } }"

function validateLabelDirective(field) {
  const d = (field.directives || []).find(d => d.name.value === 'label');
  if (d && d.arguments.length > 1) throw new Error('@label accepts at most one argument');
}

const hasValidLabelArgCount = (d) => !d || d.arguments.length <= 1;

When it happens

Trigger: A field directive `@label(v: "a", other: "b")` or any @label with len(d.Arguments) > 1 during convField, reached via Parse.

Common situations: Copy-pasted queries mixing dialects; guessing directive syntax; tools generating extra arguments on directives.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• unexpected arguments: %v (%d)
• label directive should have 'v' argument
• error parsing label: %v
• expected one predicate or path for recursive follow
• unexpected value type for %v: %T

AI-assisted analysis of cayleygraph/cayley@81dcd7d73e (2026-09-06). Data as JSON: /api/errors/3b106b1ff7998096. Report an issue: GitHub.