Billing

Aethex meters usage in credits, and credits are prepaid. Plans grant a monthly credit allocation; voice calls, TTS, transcription, and agent text chat each consume credits at their own rate. You can buy credit packs on top of your plan at any time. Aethex never bills you for usage after the fact: when your balance reaches zero, metered requests stop until you add more credits.

Aethex ships several paid self-serve tiers, each with its own monthly credit allocation, phone-number capacity, and support level. There is no free tier: a new account starts with no plan and no credits, so subscribe to a plan or buy credits before your first call. Cancelling a plan leaves you with no plan once the period you paid for ends; any credits you bought stay usable. Tier details and live pricing are on the pricing page; pick or change a plan from the billing dashboard.

Plans are denominated in credits and the dashboard shows your remaining balance as one number across features. Each feature converts to credits at a fixed rate:

Voice calls

4,000 credits per minute of conversation

Transcription

1,333 credits per minute of input audio

TTS

8 credits per character of synthesized text

Agent text chat

400 credits per 1,000 tokens (prompt + reply) of `POST /agents/{id}/chat`

Your balance has two buckets and they behave differently. Plan credits — the monthly allocation — do not roll over: whatever is left expires when the next cycle begins. Purchased credits — credit packs you buy, including auto-refill top-ups — do roll over, and are only spent once the cycle's plan allocation is used up. If you need more headroom, upgrade to a higher tier or buy a credit pack.

When your balance reaches zero, Aethex stops metered work rather than billing you for it. Voice calls, WebRTC sessions, TTS, and transcription return 402 Payment Required with code: "billing.no_credits"; read-only routes (agent lookups, usage queries) keep working. There are two ways back: buy a credit pack — list them with GET /billing/credits/packs, then POST /billing/credits/purchase — or turn on auto-refill so you never reach zero in the first place.

Auto-refill is opt-in and off by default. Pick a threshold and a pack (PUT /billing/auto-refill; a saved card is required): whenever your total balance drops to or below that threshold, Aethex buys that pack on your card and adds the credits. Every refill produces a Stripe receipt you can find under Invoices on the billing dashboard. Read your current settings with GET /billing/auto-refill, and turn it off any time with enabled: false — your threshold and pack are remembered, so switching it back on is one call.

If a charge fails (expired card, declined payment) — a subscription renewal or an auto-refill alike — the account enters dunning and metered API routes return 402 Payment Required until the payment method is fixed. After repeated declines the card is locked (billing.payg_card_repeatedly_failed) and support has to clear the lock before a new card can be attached. Read-only routes keep working throughout so you can recover without losing visibility.

Cards are stored with Stripe. Add or remove cards from the billing dashboard. A saved card is required on every self-serve account, with or without a plan. If you buy credits before adding one, the card you pay with is saved. Credit packs are paid in Stripe Checkout; the default card is used for subscription renewals, auto-refill top-ups, and any one-off invoice charges.

Renewals and plan changes generate Stripe invoices with line items and downloadable PDFs. Credit-pack purchases and auto-refill top-ups generate Stripe receipts instead, as did the retired PAYG overage charges. Every one of them appears on the billing dashboard — if we charged your card, you can find the receipt.