OpenAI

GPT-OSS 20B

OpenAI's light open model

Text

Reasoning

Tools

Type: Chat
Context: 131K tokens
Russian: medium
Input price: 1,53 ₽ / 1M tokens
Output price: 7,65 ₽ / 1M tokens
Release date: August 2025

chat/completions

import OpenAI from "openai"
const client = new OpenAI({
  baseURL: "https://api.yenisei.ru/v1",
  apiKey: process.env.YENISEI_API_KEY,
})
const stream = await client.chat.completions.create({
  model: "gpt-oss-20b",
  messages: [{ role: "user", content: "Hi!" }],
  stream: true,
})
for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content ?? "")
}

About the model

GPT-OSS 20B is the compact open model in OpenAI's lineup, with reasoning support. It is the fast, economical option: for complex tasks it switches on step-by-step analysis, and on standard ones it answers quickly. The weights are open, so you can run it yourself. The model follows instructions, is multilingual and handles Russian confidently, and it supports tool calling for agents and automation.