# Pricing and limits

> Prices per million tokens, context window, output limits and rate-limit behaviour on Serenity Edge.

Source: https://docs.serenityedge.ai/docs/pricing-and-limits/

## Prices

Prices are in US dollars per million tokens and are read from `GET /v1/models` when this page is published and again when you open it. You are billed on the `usage` object returned with every response: `prompt_tokens` at the input price, of which `prompt_tokens_details.cached_tokens` at the cached input price, and `completion_tokens` at the output price. Reasoning tokens count as output tokens.

| Model | Input | Output | Cached input |
| --- | --- | --- | --- |
| `orion-pro` | $0.144 | $1.50 | $0.036 |
| `orion-plus` | $0.101 | $0.60 | $0.025 |
| `qwen3.8-27b` | $0.144 | $1.50 | $0.036 |
| `qwen3.6-35b-a3b` | $0.101 | $0.60 | $0.025 |
| `paddleocr-vl-1.6` | $0.016 | $0.016 | n/a |

Read from the API (`GET /v1/models`) when this page was published, on 6 November 2026, 19:49 UTC.

Images count as prompt tokens. A full page sent to `paddleocr-vl-1.6` for [document OCR](https://docs.serenityedge.ai/docs/models/#document-ocr) is about 1,250 prompt tokens.

These are the prices of direct access to the API with a Serenity Edge API key. An [enterprise contract](https://docs.serenityedge.ai/docs/access/enterprise/) may set committed-use rates. With a key from a [Serenity Star account](https://docs.serenityedge.ai/docs/access/serenity-star-account/), Serenity Star bills your usage at the prices of that account. Through a [router or marketplace](https://docs.serenityedge.ai/docs/access/channels/), that platform bills you under its own terms and shows its own prices.

### Cached input

When the beginning of a prompt repeats across requests (a long system prompt, a shared document, the earlier turns of a conversation), the matching prefix can be served from the prompt cache and is billed at the cached input price. The number of cached tokens is reported in `usage.prompt_tokens_details.cached_tokens` (`usage.input_tokens_details.cached_tokens` on the [Responses API](https://docs.serenityedge.ai/docs/responses-api/)). To benefit, keep the stable part of the prompt at the start and the variable part at the end.

The cache works in blocks of tokens, so a prefix is cached only when it repeats over more than about 2,000 tokens (about 4,000 on `orion-plus` and `qwen3.6-35b-a3b`), and the cached part is a whole number of blocks; a shorter prompt is billed entirely at the input price. Every request of a conversation is sent to the server that already holds its prefix, so the earlier turns of a conversation are cached as long as you send them unchanged.

## Decision models

> **Preview**
> 
> Decision models are in public preview. Their availability will be announced in the [release notes](https://docs.serenityedge.ai/release-notes/).

[Decision models](https://docs.serenityedge.ai/docs/decisions/) are billed on input tokens only: `usage.input_tokens` of each reply at the input price below. Output is not billed, and there is no cached input price. The model reads the input together with each question, so the input tokens of a request grow with the number of questions as well as with the length of the input. Prices are in US dollars per million input tokens and are read from `GET /v1/models?format=openai` when this page is published and again when you open it. On `orion-compass-flash` and `d3`, the tokens of a request's images are input tokens too: `usage.input_tokens` counts them, and `usage.input_tokens_details.image_tokens` (`usage.image_tokens` on `POST /v1/systemone`) shows their part.

| Model id | Context | Reads | Input | Output | Endpoints |
| --- | --- | --- | --- | --- | --- |
| `d3`, also `vllm-sr/d3` | 24,576 | text, image | $0.042 | Free | /v1/decisions, /v1/systemone |
| `orion-compass`, alias of `orion-compass-26.1` | 32,000 | text | $0.034 | Free | /v1/decisions, /v1/systemone |
| `orion-compass-flash`, alias of `orion-compass-flash-26.1` | 32,000 | text, image | $0.017 | Free | /v1/decisions, /v1/systemone |

Read from the API (`GET /v1/models?format=openai`) when this page was published, on 6 November 2026, 19:49 UTC.

A decision request whose input and questions do not fit the context length is refused with `code: "context_length_exceeded"` rather than truncated. Rate limits and capacity work as for chat completions: see below.

## Embeddings, rerank and redaction

The models of `POST /v1/embeddings`, `POST /v1/rerank` and `POST /v1/redact` are billed on input tokens only, at the price below; output is not billed, and there is no cached input price. Prices are in US dollars per million tokens and are read from `GET /v1/models?format=openai` when this page is published and again when you open it. See [Embeddings, rerank and redaction](https://docs.serenityedge.ai/docs/embeddings-rerank-and-redaction/) for worked examples.

| Model id | Input | Endpoint |
| --- | --- | --- |
| `privacy-filter`, also `openai/privacy-filter` | $0.009 | /v1/redact |
| `qwen3-embedding-0.6b`, also `qwen/qwen3-embedding-0.6b` | $0.008 | /v1/embeddings |
| `qwen3-reranker-0.6b`, also `qwen/qwen3-reranker-0.6b` | $0.008 | /v1/rerank |

Read from the API (`GET /v1/models?format=openai`) when this page was published, on 6 November 2026, 19:49 UTC.

| Route | Billed tokens | Per request |
| --- | --- | --- |
| `POST /v1/embeddings` | `usage.prompt_tokens` of the answer: each input's own tokens, as the model counts them | At most 512 inputs and about 300,000 tokens (a quarter of the characters), each input read up to its first 8,192 tokens; body up to 4 MB |
| `POST /v1/rerank` | Estimated per document as `ceil((characters(query) + characters(document)) / 4)`, added up and returned in `usage` | At most 1000 documents, a query of 4096 characters and about 300,000 tokens (the estimate in the previous column); body up to 4 MB |
| `POST /v1/redact` | Estimated as `ceil(characters of all inputs / 4)`; the answer has no `usage` | At most 256 inputs; body up to 192 KiB (196,608 bytes) |

Characters are Unicode code points, not bytes. If an embeddings answer ever comes without `usage`, it is billed on an estimate instead: a quarter of the characters of each string, rounded up. A request over a limit is refused before it reaches the model: HTTP 400 for too many inputs or documents, HTTP 413 for a body that is too large. Rate limits and capacity work as for chat completions: see below.

## Context and output limits

The context window (input plus output) and the maximum output (`max_tokens`) of each model are shown in the [catalogue](https://docs.serenityedge.ai/docs/models/#catalogue) and returned by `GET /v1/models`. A request whose messages exceed the context window is rejected with HTTP 400. A response that reaches `max_tokens` or the end of the context window returns `finish_reason: "length"`.

## Rate limits

Every API key has a request-per-minute and a token-per-minute allowance. When you exceed it the API returns **HTTP 429** with a `Retry-After` header stating how many seconds to wait, and an [error object](https://docs.serenityedge.ai/docs/errors-and-rate-limits/) of type `rate_limit_error`.

Handle 429 with exponential backoff and honour `Retry-After`. The OpenAI SDKs retry 429 automatically; see [Errors and rate limits](https://docs.serenityedge.ai/docs/errors-and-rate-limits/) for details and for how to request a higher limit.

## Capacity

Serenity Edge runs on Substrate AI's own GPUs in Spain, not on a hyperscaler. Capacity is added in steps as new hardware comes online. During peaks the API may respond with HTTP 429 and a `Retry-After` header rather than degrade latency for everyone; handle it like any other 429. If you need guaranteed throughput, an [enterprise contract](https://docs.serenityedge.ai/docs/access/enterprise/) reserves capacity for you.