Skip to content
tacita.chat
Docs · Billing & credits for API usage

Developers

Billing & credits for API usage

How API calls are charged — by actual usage, never above the listed price, free daily credits first, then paid credits — and how spend limits interact.

On this page

API usage is billed to the wallet that owns the key, exactly as if you used the app.

  1. Free daily credits are spent first. You get them if you hold the token: $0.50, $0.80, $1.50 or $3.00 a day, depending on your tier. They reset at 00:00 UTC and don't carry over.
  2. Then paid credits. Top up by sending ETH or USDG on Robinhood Chain to the treasury. See Paid credits.
  3. Then the request fails. If neither is enough, the request gets 402 insufficient_credits and nothing is charged.

You pay for what you use#

ModeWhat you're charged
Anonymous (market price)What the request actually cost on the compute market, never more than the listed price. It is usually below it.
TEE (list price)The listed price, exactly. Not available through the API yet.

GET /v1/models shows each model's listPrice and, for anonymous models, the current marketPrice. Prices are per 1 million tokens for text, per image, or per video job. See Models & modes.

How a request is charged#

  • Before the call, we reserve an upper bound, based on the listed price, your prompt size and max_tokens (default 4096). If you can't cover it, you get 402 right away. A smaller max_tokens lowers the reservation.
  • After the call, you're charged the real cost from the reported usage, and the rest of the reservation is released straight away.
  • If the provider fails, you are not charged: the reservation is released in full.
  • If you abort a stream early, you pay for the prompt and the part of the answer that was already generated.
  • Images and video are reserved at the listed price and charged at the real cost.

Spend limits#

A key's monthly spend limit caps what that key can spend, whether from free or paid credits. Once it's hit, the key gets 402 spend_limit_reached until the month resets, while other keys and the app keep working. Change or remove the limit on the Developers page.

Checking usage#

  • The Developers page shows each key's spend this month.
  • Your wallet's balances (free credits left today, paid balance) are on your account page.
  • Each response's usage field has the token counts for that call.