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

# Compatibility and request fields

> Understand the supported OpenAI-compatible subset

Mibyan accepts the common text-generation fields used by OpenAI-compatible clients. The gateway validates and normalizes the request before it reaches the model service.

## Supported request fields

| Field               | Chat Completions  | Responses                           | Notes                                                     |
| ------------------- | ----------------- | ----------------------------------- | --------------------------------------------------------- |
| `model`             | Yes               | Yes                                 | Use `mibyan-4.1`                                          |
| `messages`          | Yes               | Yes                                 | Roles: `system`, `developer`, `user`, `assistant`, `tool` |
| `input`             | No                | Yes                                 | String or message array                                   |
| `instructions`      | No                | Yes                                 | Converted to a developer message                          |
| `stream`            | Yes               | Yes                                 | SSE output                                                |
| `max_tokens`        | Yes               | Accepted through normalized request | Integer from 1 to 32,000                                  |
| `max_output_tokens` | No                | Yes                                 | Normalized to the generation limit                        |
| `temperature`       | Yes               | Yes                                 | `0` to `2`                                                |
| `top_p`             | Yes               | Yes                                 | `0` to `1`                                                |
| `frequency_penalty` | Yes               | Yes                                 | `-2` to `2`                                               |
| `presence_penalty`  | Yes               | Yes                                 | `-2` to `2`                                               |
| `stop`              | Yes               | Yes                                 | String or a short list                                    |
| `tools`             | Yes, when enabled | Model-dependent                     | Definitions are size-limited                              |
| `tool_choice`       | Yes, when enabled | Model-dependent                     | Passed only when tools are accepted                       |
| `response_format`   | Model-dependent   | Model-dependent                     | Requires structured-output access                         |

Unknown fields are ignored for forward compatibility.

## Message content

Text content can be a string. Structured content arrays are accepted only when the active model and endpoint support them; unsupported media or file parts should be rejected by your integration rather than assumed to work.

## Not currently exposed

The public API does not currently expose embeddings, image generation, audio generation, file storage, background mode, hosted tools, or conversations. Watch the [changelog](/changelog) for availability changes.

## Stable contract

Use the documented base URL, model ID, error envelope, request ID, and standard response fields.