Step 3.7 Flash - Kyma API

Overview

Created by stepfun, it supports a 256,000-token context window and accepts text, image, and video inputs while returning text. It includes native support for tool calling, reasoning, and structured outputs. On Kyma, requests are routed through an OpenAI-compatible endpoint with automatic failover if a serving path degrades. Prompt prefixes are cached at this model’s cached input rate. The model caps output at 8,192 tokens, making it suitable for conversational and extraction workflows rather than long-form generation.

Specs

Field	Value
Model ID	`step-3.7-flash`
Best for	Cheap fast throughput, multimodal input, bulk tasks
Context window	256,000
Max output tokens	8K
Input modalities	Text, Image, Video
Output modalities	Text
Tool calling	Yes
Structured outputs	Yes
Prompt caching	Yes
Speed	Fast
Cost band	Cheap
Release stage	Stable

Pricing

	Per 1M tokens
Input	$0.27
Output	$1.55

Use this when

Bulk Chat Processing — Route high-volume conversational workloads with low latency and minimal overhead.
Multimodal Input Analysis — Extract information from text, images, and video streams in a single request.
Tool-Driven Workflows — Execute function calls and structured data extraction for automated pipelines.
Long-Context Summarization — Process documents up to 256K tokens while maintaining fast response times.

Not ideal for

It is not suited for tasks requiring outputs longer than 8,192 tokens or heavy creative writing where maximum reasoning depth is prioritized over speed and cost.

Pick something else when

You need deeper reasoning or longer outputs: use qwen-3.7-max or gpt-5.6-terra.
You need specialized code generation: use qwen-3-coder or kimi-k3.
You need higher-tier multimodal reasoning: use gemini-3.5-flash-lite or gemini-3.6-flash.

Example

from openai import OpenAI

client = OpenAI(base_url="https://kymaapi.com/v1", api_key="ky-...")

response = client.chat.completions.create(
    model="step-3.7-flash",
    messages=[{"role": "user", "content": "..."}],
    tools=[...],  # function calling supported
)

Agent query example

Ask the API which models fit, instead of hardcoding an id:

curl "https://kymaapi.com/v1/models?recommended_for=chat&tools=true&quality_tier=strong"

FAQ

Does this model support image and video inputs? Yes, it accepts text, image, and video inputs and returns text outputs. How does prompt caching work with this model on Kyma? Repeated prompt prefixes are billed at this model’s cached input rate, and Kyma automatically reroutes requests if a serving path degrades. What is the maximum output length? The model caps generation at 8,192 tokens per request.

​Overview

​Specs

​Pricing

​Use this when

​Not ideal for

​Pick something else when

​Example

​Agent query example

​FAQ