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

# Engines

> Every engine version in the registry, with its limits and conformance results.

An engine turns a document's compiled context and your typed questions into probability distributions. You always name one, and nothing chooses for you: an exact version stays that version, and `current` follows the provider, with the epoch of model behaviour recorded on every answer and its quality re-checked against the conformance suite every day and after every change we detect. Only `active` versions can be pinned by a new judgment, and `GET /engines` lists those. If an exact version your judgments have used is retired, your organization's owners and admins get an email. Judging costs the same on every engine: you pay per [judgment](/pricing#judgments), by size class.

Laya, a small engine we host ourselves for short text, is coming. It gets a page here once its first version passes the conformance suite; until then, use Jev `current`.

| Version | Status | Context | Conformance run |
| - | - | - | - |
| [jev current](/engines/jev-current) | `active` | 32,000 tokens | 2026-09-27 |


## Related topics

- [List active engine versions](/api-reference/engines/list-active-engine-versions.md)
- [Change budget, pinning and default engine](/api-reference/namespaces/change-budget-pinning-and-default-engine.md)
- [System behavior](/behavior.md)
- [Judgments](/concepts/judgments.md)
- [Writing a context recipe](/guides/context-recipes.md)


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