Does Step 5 Preview support zero data retention?

No. The routes serving Step 5 Preview retain content; see the per-route data-handling section for each route's logging stance and retention window.

Where is Step 5 Preview hosted?

See the per-route table for Step 5 Preview hosting locations and residency details.

Is Step 5 Preview trained on prompts and outputs?

No. Every hosting route for Step 5 Preview is configured so customer prompts and outputs are not used to train models by default.

Is a GDPR DPA available for Step 5 Preview?

Yes. A GDPR Data Processing Agreement is available on at least one route serving Step 5 Preview. Contact hello@opper.ai to receive it.

Step 5 Preview

by StepFun

Step 5 Preview is the new flagship model from StepFun, the Shanghai AI lab. It is a sparse mixture-of-experts model with 600B total parameters, of which 27B are active per token. StepFun positions it for agentic work, targeting frontier-level performance in software engineering and professional knowledge work, with particular strength in finance. The model accepts text, images and video as input and returns text. It has a 1M-token context window and can produce up to 64k output tokens, so it can hold a large codebase, a long document set or an extended agent history in one conversation. It supports tool calling, JSON Schema structured output and streaming, and it reasons before answering. As a preview release, its behavior and availability may change before a final version.

Call Step 5 Preview on Opper with the OpenAI SDK. Sign up without a credit card. Get started

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Key info

Input

Output

Features

Context window

Max output

66K

Input price

$1.00 /1M$0.05 cache read

Output price

$2.70 /1M

No training by default
GDPR DPA available

Available routes

Step 5 Preview runs on 1 route through the Opper gateway. Compare residency, zero data retention and training posture at a glance, with full data-handling detail per route below.

Provider	Region	Zero data retention	Training	Input	Output	Cache read
Tencent Cloud	Multi		No	$1.00	$2.70	$0.05

Data handling per route

Each route hosting Step 5 Preview has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.

Tencent Cloud — Multi-region

Content is retained: limited debug logs, 30-day retention. No training on customer data. GLOBAL; SCCs; DPA available.

Zero data retention: Retained: limited debug logs, 30-day retention.
Training: No training on customer data.
Logging: Limited debug logs (30-day retention)
Abuse monitoring: On by default, holds flagged content
Caching: Content cached for replay
GDPR DPA: DPA available
Transfer mechanism: SCCs

Get started

Call Step 5 Preview through the Opper gateway with one API key. Opper is drop-in compatible with the OpenAI, Anthropic and Google AI SDKs.

Step 5 Preview is a premium model on Opper. Sign up needs no credit card: you get an API key straight away and the free models work in the playground and the API. Add a card to use premium models, pay-as-you-go with no minimum.

Set it up with your agent

Copy this and paste it into a coding agent like Claude Code, Cursor or Codex and it'll wire up Opper for you.

Or call it directly

1import OpenAI from "openai";
2
3const client = new OpenAI({
4  apiKey: process.env.OPPER_API_KEY,
5  baseURL: "https://api.opper.ai/v3/compat",
6});
7
8const completion = await client.chat.completions.create({
9  model: "tencent:sg/step-5-preview",
10  messages: [{ role: "user", content: "Hello" }],
11});
12console.log(completion.choices[0].message.content);