PHP token bucket rate limiter

<?php
final class TokenBucket
{
    private float $tokens;
    private int $updated;

    public function __construct(private float $rate, private int $burst)
    {
        $this->tokens = (float) $burst;
        $this->updated = time();
    }

    public function take(int $cost = 1): bool
    {
        $now = time();
        $this->tokens = min($this->burst, $this->tokens + ($now - $this->updated) * $this->rate);
        $this->updated = $now;
        if ($this->tokens < $cost) return false;
        $this->tokens -= $cost;
        return true;
    }
}