How do I use Hy4 preview through YepAPI?

Sign up for a free API key, then send requests to the /v1/ai/chat endpoint.

TencentText Generation/v1/ai/chat

Hy4 preview

Access Hy4 preview through one API key. Tencent Hunyuan 4 Preview Coding Agent MoE.

Hy4 preview is a mixture-of-experts model from Tencent with 49B active parameters out of 770B total, designed for coding agents, complex tool-use workflows and productivity tasks. Hy4 preview is a large, mid-priced model for coding agents and tool-heavy workflows; as a preview, expect it to change before a stable release.

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2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see Hy4 preview respond in real time.

POST/v1/ai/chattencent/hy4-preview

Message *

Max Tokens

Maximum tokens in the response.

Stream

Real-time tokens

Hit "Send Request" to see the response

Context Window

1.0M tokens

Max Output

64K tokens

Input Price

$1.23 / 1M tokens

Output Price

$3.69 / 1M tokens

Strengths

✓

770B MoE, 49B active

A large mixture-of-experts model tuned for coding and tool use.

✓

Complex tool workflows

Designed for agents that chain many tool calls.

✓

1M context, 64K output

Handles up to 1,048,576 input tokens and returns up to 64,000 output tokens per call.

✓

Preview release

Behaviour may change before Tencent's stable Hy4.

Quick start

Copy this snippet and start making calls with Hy4 preview.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "tencent/hy4-preview",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Why use Hy4 preview through YepAPI?

✓One API key for all models — no separate accounts

✓OpenAI SDK compatible — just change the base URL

✓No monthly minimums — pay per token

✓Switch models with one line of code

✓Full provider passthrough — citations, search results, and all extras included

✓Streaming and non-streaming support on every model

✓Works with Cursor, Claude, LangChain, and any LLM tool

✓Unified billing across all providers

Hy4 preview API — pricing, context window & access

Hy4 preview is a mixture-of-experts model from Tencent with 49B active parameters out of 770B total, designed for coding agents, complex tool-use workflows and productivity tasks. It pairs a 1,048,576-token context window with up to 64,000 output tokens per response, at $1.23 per 1M input and $3.69 per 1M output tokens through YepAPI.

Through YepAPI you call Hy4 preview on an OpenAI-compatible endpoint with a single key — the same key that reaches GPT-6, Claude, Gemini, Grok and the SEO, SERP and scraping APIs. Input: text.

What is Hy4 preview?

Hy4 preview is a mixture-of-experts model from Tencent with 49B active parameters out of 770B total, designed for coding agents, complex tool-use workflows and productivity tasks. It offers a 1,048,576-token context window and up to 64,000 output tokens at $1.23 / $3.69 per 1M tokens. It accepts text as input, handles up to 1,048,576 tokens of context and returns up to 64,000 output tokens per call.

Build with Hy4 preview via YepAPI

YepAPI serves Hy4 preview on the OpenAI-compatible /v1/ai/chat endpoint. Point your base URL at YepAPI, add your key, and set the model string to hy4-preview (or the full tencent/hy4-preview). Function calling, structured outputs and reasoning settings pass straight through, and switching to any other model on the platform is a one-string change per request.

Hy4 preview API pricing — $1.23 / 1M input, $3.69 / 1M output

Hy4 preview costs $1.23 per 1M input tokens and $3.69 per 1M output tokens through YepAPI, pay per token with no minimums. Failed calls are never charged, and every request is itemised in your dashboard API Logs so you can see exactly what a 64,000-token response cost.

Hy4 preview use cases

Hy4 preview is a large, mid-priced model for coding agents and tool-heavy workflows; as a preview, expect it to change before a stable release.

Try Hy4 preview free

Every new YepAPI account includes $5 in free credit with no card required — enough to test Hy4 preview on your own prompts before committing to paid usage. Create an account, copy your key, and call hy4-preview right away.