# Step 3.7 Flash — API, capabilities & pricing | Y-API

> Step 3.7 Flash combines a sparse language backbone with a vision encoder. Its publisher emphasizes perception plus tool orchestration; the OpenRouter entry lists image and video input and selectable reasoning effort.

This is the markdown representation of https://y-api.bestvirtualgoods.com/models/stepfun/step-3.7-flash. Generated by `scripts/generate-seo-assets.mjs` from the same copy the page renders — do not edit by hand.

Model ID: `stepfun/step-3.7-flash`

Sources reviewed: 2026-10-04. Y-API catalog snapshot: 2026-10-04.

## Choosing this model

Selection advice by Y-API. The checks below are suggested evaluations, not published test results.

### Where to start

Evaluate it on structured extraction followed by a consistency check: recover chart values or document fields, then verify the arithmetic with an external tool. Separate perception errors from reasoning errors.

### What to watch for

The Flash name does not supply a latency guarantee, and the gateway’s accepted media formats may be narrower than the reference. Verify each reasoning setting rather than assuming the native provider’s configuration maps directly.

## Model specifications

These are OpenRouter model-level specifications, not a Y-API compatibility test. A particular route may accept fewer input formats, parameters or tokens. Verify the features you need with a small request; a successful text response does not validate vision or tool calling.

| Field | Value |
| --- | --- |
| Context window | 262,144 tokens |
| Input | Text, Image, Video |
| Output | Text |
| Listed on OpenRouter | 2026-05-28 |
| Parameters listed by OpenRouter | `frequency_penalty`, `include_reasoning`, `logprobs`, `max_tokens`, `presence_penalty`, `reasoning`, `reasoning_effort`, `repetition_penalty`, `response_format`, `seed`, `stop`, `structured_outputs`, `temperature`, `tool_choice`, `tools`, `top_k`, `top_logprobs`, `top_p` |

## Estimate your cost

| Price basis | Input / 1M tokens | Output / 1M tokens |
| --- | --- | --- |
| Account credit | $0.20 | $1.20 |
| Cash equivalent | $0.02 | $0.12 |

$1 paid adds $10 of credit. Cash equivalent = credit consumed ÷ 10; this is not the model publisher’s list price.

Input tokens / request: 1000. Output tokens / request: 500. Number of requests: 1000.

Estimated credit consumed: $0.80. Estimated cash equivalent: $0.08.

Illustrative token budget, not measured usage or a quote. Includes input and output; excludes separate media charges, cache discounts and retries. Include billed reasoning tokens in your output budget where applicable. Actual billing follows usage returned by the service.

### Same token budget, different models

| Model | Estimated credit consumed | Estimated cash equivalent |
| --- | --- | --- |
| [Step 3.7 Flash](https://y-api.bestvirtualgoods.com/models/stepfun/step-3.7-flash) | $0.80 | $0.08 |
| [Qwen3.8 Flash](https://y-api.bestvirtualgoods.com/models/qwen/qwen3.8-flash) | $0.45 | $0.045 |
| [GLM 5.3 Flash](https://y-api.bestvirtualgoods.com/models/z-ai/glm-5.3-flash) | $0.40 | $0.04 |

## Use the API

These minimal, text-only requests use the exact Y-API model ID. They do not demonstrate image, audio, video, file or tool support. The output limit also needs room for reasoning; an empty answer with finish_reason=length can mean the budget was exhausted.

Set the TOKEN environment variable to a key from your console. Run this on your server or locally; never expose a key in browser code or a public repository.

### A task to try

An invoice lists items at 30 and 45, tax of 15 and a total of 100. Check the arithmetic and identify exactly which value is inconsistent.

```bash
curl --fail-with-body --silent --show-error --max-time 120 \
  'https://api.y-api.bestvirtualgoods.com/v1/chat/completions' \
  -H "Authorization: Bearer ${TOKEN:?Set TOKEN first}" \
  -H 'Content-Type: application/json' \
  --data-binary @- <<'JSON'
{
  "model": "stepfun/step-3.7-flash",
  "messages": [
    {
      "role": "user",
      "content": "An invoice lists items at 30 and 45, tax of 15 and a total of 100. Check the arithmetic and identify exactly which value is inconsistent."
    }
  ],
  "max_tokens": 4096
}
JSON
```

```python
import json
import os
import sys
import urllib.error
import urllib.request

payload = {
  "model": "stepfun/step-3.7-flash",
  "messages": [
    {
      "role": "user",
      "content": "An invoice lists items at 30 and 45, tax of 15 and a total of 100. Check the arithmetic and identify exactly which value is inconsistent."
    }
  ],
  "max_tokens": 4096
}

request = urllib.request.Request(
    "https://api.y-api.bestvirtualgoods.com/v1/chat/completions",
    data=json.dumps(payload).encode("utf-8"),
    headers={
        "Authorization": "Bearer " + os.environ["TOKEN"],
        "Content-Type": "application/json",
    },
    method="POST",
)
try:
    with urllib.request.urlopen(request, timeout=120) as response:
        result = json.load(response)
    print(json.dumps(result, ensure_ascii=False, indent=2))
except urllib.error.HTTPError as error:
    print(error.read().decode("utf-8"), file=sys.stderr)
    raise SystemExit(1)
```

### How to evaluate the result

The components sum to 90, but the evidence does not show which source field is wrong. A good answer flags the inconsistency without silently changing the invoice.

## Before you choose

### What should I compare with other Flash models?

Use extraction accuracy, schema validity, completed tool calls and total tokens on the same inputs. Measure endpoint latency yourself instead of interpreting Flash as a standardized speed class.

## Sources & scope

Technical facts come from the cited model page and, where available, its linked publisher card. A card describes that checkpoint; it is not proof of the weights a gateway serves. Prices come only from the Y-API catalog. We do not claim measured latency, uptime or benchmark scores for this endpoint.

- [OpenRouter model page & specifications](https://openrouter.ai/stepfun/step-3.7-flash)
- [Publisher model card linked by OpenRouter](https://huggingface.co/stepfun-ai/Step-3.7-Flash)
- [Y-API catalog & prices (JSON)](https://y-api.bestvirtualgoods.com/models.json)

## Models to compare

Compare these alternatives on the same inputs. Their descriptions explain different roles; a lower price does not establish equivalent quality.

### [Qwen3.8 Flash](https://y-api.bestvirtualgoods.com/models/qwen/qwen3.8-flash)

Qwen3.8 Flash is Alibaba’s multimodal reasoning entry for text, images and video in the OpenRouter catalog. It brings document and chart understanding into the same model selection as coding assistance and long-context analysis.

### [GLM 5.3 Flash](https://y-api.bestvirtualgoods.com/models/z-ai/glm-5.3-flash)

GLM 5.3 Flash introduces native multimodality to the GLM 5 series. Unlike the text-only GLM 5.3 entry, its new base architecture combines sparse and linear attention for visual and long-context workloads.

## Links

- HTML version of this page: https://y-api.bestvirtualgoods.com/models/stepfun/step-3.7-flash
- Site index for agents: https://y-api.bestvirtualgoods.com/llms.txt
- Full reference (single file): https://y-api.bestvirtualgoods.com/llms-full.txt
- OpenAPI 3.1 spec: https://y-api.bestvirtualgoods.com/openapi.json
- Model catalog (JSON, no key needed): https://y-api.bestvirtualgoods.com/models.json
- API base URL: `https://api.y-api.bestvirtualgoods.com/v1`
- Contact: support@bestvirtualgoods.com
- Model catalog: https://y-api.bestvirtualgoods.com/models
- Integration guide: https://y-api.bestvirtualgoods.com/docs