# 2026-09-25 — Balance and spending limit errors now return 402 (improvement · API, CLI · BREAKING)

> Running out of balance or hitting a key's spending limit now returns 402 Payment Required, so 429 only ever means slow down.

`INSUFFICIENT_BALANCE` used to return `422` and `SPENDING_LIMIT_EXCEEDED` used to return `429`. Both now return `402 Payment Required`. The `code` and `message` in the body are the same.

The old `429` looked like a rate limit, so HTTP clients that retry `429` kept resending a request that could only succeed once the key's period rolled over. Now a `429` means back off and retry, and a `402` means top up, raise the cap, or wait for the period to reset.

If your code checks `code`, nothing changes. If it checks the status, look for `402` where you looked for `422` or `429`:

```ts
if (error instanceof MynthAPIError && error.status === 402) {
  // error.code is INSUFFICIENT_BALANCE or SPENDING_LIMIT_EXCEEDED
}
```

The CLI still exits with `4` for both codes, and now also for any other `402`.

Permalink: https://mynth.io/changelog/2026-09-25-billing-errors-402 · Markdown: https://mynth.io/changelog/2026-09-25-billing-errors-402.md