src/Agent.php
public function setUserAttributes(string $user, string $account, string $product): bool
    {
        if (!$this->isLoaded()) {
            return false;
        }

        return newrelic_set_user_attributes($user, $account, $product);
    }
public function setUserAttributes(string $user, string $account, string $product): bool
    {
        if (!$this->isLoaded()) {
            return false;
        }

        return newrelic_set_user_attributes($user, $account, $product);
    }
Create user-related custom attributes. newrelic_add_custom_parameter is more flexible.

Agent version 3.1.5.111 or higher.

@see https://docs.newrelic.com/docs/agents/php-agent/php-agent-api/newrelic_set_user_attributes
@see self::addCustomParameter

@param string $user    Specify a name or username to associate with this page view
@param string $account Specify the name of a user account to associate with this page view
@param string $product Specify the name of a product to associate with this page view

@return bool