# Step 5 Preview

> StepFun's flagship for agentic work, a 600B MoE with 27B active: repeated tool calls, execution, verification and revision over long context. 1M context, image input, reasoning. Preview release.

Human version: https://kymaapi.com/models/step-5-preview
Live JSON: `GET https://kymaapi.com/v1/models` (no auth required)

## Facts

- **Model ID**: `step-5-preview`: pass this as `model` in the request body
- **Creator**: StepFun
- **Released**: 2026-10-08
- **Context window**: 1M tokens
- **Max output**: 64K tokens per response, a hard ceiling, not a default
- **Price**: $1.35 in / $3.645 out per 1M, cached input $0.135 per 1M
- **Capabilities**: tools, vision, reasoning, caching

## Call it

```bash
curl https://kymaapi.com/v1/chat/completions \
  -H "Authorization: Bearer $KYMA_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "step-5-preview", "messages": [{"role": "user", "content": "Hello"}]}'
```

## See also

- All models: https://kymaapi.com/models.md
- Pricing: https://kymaapi.com/pricing.md
- Other models by StepFun: https://kymaapi.com/models?q=StepFun