> ## Documentation Index
> Fetch the complete documentation index at: https://docs.paywalls.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Pricing & Metering

<Note>
  Pricing is rule‑based and model‑aware so you can balance UX and margins
  without changing code.
</Note>

## Concepts

* Per‑model rules — set different prices per model so users can self‑select price/performance.
* Layers you can combine:
  * Per request — a flat fee per API call (great for tools/actions and short prompts) (soon).
  * Per token — meter prompt + completion tokens (finalized after generation/stream end).
  * Hybrid — minimum fee + per‑token to keep margins predictable across varied prompts (soon).
  * Credits/promos — trial or promo balances to reduce onboarding friction.

<Info>
  You control pricing in the dashboard per model. Typical fields include
  prompt/completion prices (per million tokens), per‑request minimum fee, and
  optional markup.
</Info>

## Per‑model dynamic pricing

Use model‑specific prices to match cost and value:

* Budget chat (e.g., `openai/gpt-4o-mini`): lower per‑token, low minimum.
* Premium reasoning (e.g., larger models): higher per‑token and/or higher minimum.
* Tool‑heavy agents: small minimum + manual per‑tool fees (see Manual charges below).

## Metering details

* Token accounting — prompt and completion tokens are computed per request.
* Streaming — token totals are finalized at the end of the stream; charges are written to the ledger then.
* Retries — if you retry a non‑idempotent POST (e.g., a manual charge) use the same `Idempotency-Key` so you don’t double‑charge.
* Combination — automatic token charges and your manual charges can coexist in the same ledger period.