Step 5 Preview
stepfun/step-5-preview
Step 5 Preview is StepFun's flagship model for coding, software engineering, and professional knowledge work. Its sparse MoE architecture uses 600B total and 27B active parameters, with a 1M-token context window and up to 64K output tokens. It accepts text, images, and video and supports tool calling, structured JSON output, three reasoning effort levels, streaming, and prompt caching.
Features
Serverless API
Docs
stepfun/step-5-preview is available via Novita's serverless API, where you pay per token. There are several ways to call the API, including OpenAI-compatible endpoints with exceptional reasoning performance.
Available Serverless
Run queries immediately, pay only for usage
Input$1 / M Tokens
Cache Read$0.1 / M Tokens
Output$2.7 / M Tokens
Use the following code examples to integrate with our API:
1from openai import OpenAI
2
3client = OpenAI(
4 api_key="<Your API Key>",
5 base_url="https://api.novita.ai/openai"
6)
7
8response = client.chat.completions.create(
9 model="stepfun/step-5-preview",
10 messages=[
11 {"role": "system", "content": "You are a helpful assistant."},
12 {"role": "user", "content": "Hello, how are you?"}
13 ],
14 max_tokens=64000,
15 temperature=0.7
16)
17
18print(response.choices[0].message.content)Info
Provider
StepFun
Quantization
-
Supported Functionality
Context Length
977K
Max Output
63K
Serverless
Supported
Function Calling
Supported
Structured Output
Supported
Reasoning
Supported
Anthropic API
Supported
Input Capabilities
text, image, video
Output Capabilities
text
Everything you need to build production AI.
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