src/Routing/RouteRegistration.php
public function field(string $field, string $inverse = null): self
    {
        $this->defaults = array_merge($this->defaults, [
            ResourceRegistrar::PARAM_RELATIONSHIP_NAME => $field,
            ResourceRegistrar::PARAM_RELATIONSHIP_INVERSE_TYPE => $inverse ?: Str::plural($field),
        ]);

        return $this;
    }
public function field(string $field, string $inverse = null): self
    {
        $this->defaults = array_merge($this->defaults, [
            ResourceRegistrar::PARAM_RELATIONSHIP_NAME => $field,
            ResourceRegistrar::PARAM_RELATIONSHIP_INVERSE_TYPE => $inverse ?: Str::plural($field),
        ]);

        return $this;
    }
Set the route's relationship field name and inverse resource type.

@param string $field
@param string|null $inverse
@return $this