> ## Documentation Index
> Fetch the complete documentation index at: https://docs.comfy.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Use Crystal Upscaler with Comfy Router

> Call fal/crystal-upscaler through Comfy Router: endpoint, request shape and the response Router returns.

API Reference for `fal/crystal-upscaler`, served by Comfy Router from fal.

**Input:** Image · **Output:** Image

## Quick start

Create a key in [your Comfy workspace](https://platform.comfy.org/profile/api-keys?onboarding=router) and export it as `COMFY_API_KEY`. The Python and TypeScript snippets use the Comfy SDKs (`pip install comfy-sdk` and `npm install @comfyorg/sdk`); the cURL snippet is the same call over raw HTTP.

**Model ID:** `fal/crystal-upscaler`

**Endpoint:** `POST https://api.comfy.org/v2/models/fal/crystal-upscaler`

**Wait for the result**

```python Python theme={null}
from comfy_sdk import Comfy

# Reads COMFY_API_KEY from the environment.
# The SDK automatically creates an idempotency key and reuses it for automatic retries.
with Comfy() as client:
    result = client.models.run(
        "fal/crystal-upscaler",
        {
            "image_url": "https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png",
            "scale_factor": 2,
        },
    )

print(result)
```

```typescript TypeScript theme={null}
import { comfy } from "@comfyorg/sdk";

// Reads COMFY_API_KEY from the environment.
// The SDK automatically creates an idempotency key and reuses it for automatic retries.
const { data } = await comfy.models.run("fal/crystal-upscaler", {
  image_url: "https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png",
  scale_factor: 2,
});

console.log(data);
```

```bash cURL theme={null}
curl https://api.comfy.org/v2/models/fal/crystal-upscaler \
  -H "X-API-Key: $COMFY_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d "{\"image_url\": \"https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png\", \"scale_factor\": 2}"
```

**Queue and collect later**

The same body, sent to `POST https://api.comfy.org/v2/models/fal/crystal-upscaler/requests`. Router answers `201` with a `request_id` as soon as the run is admitted, and the result is collected once it is ready, from this process or another one. [Queued delivery](https://docs.comfy.org/development/comfy-router/queue.md) walks through status, cancellation and collection.

```python Python theme={null}
import asyncio
from comfy_sdk import AsyncComfy

# Reads COMFY_API_KEY from the environment.
# Each submit() call mints its own Idempotency-Key and reuses it for automatic retries.
async def main():
    async with AsyncComfy() as client:
        handle = await client.models.submit(
            "fal/crystal-upscaler",
            {
                "image_url": "https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png",
                "scale_factor": 2,
            },
        )
        print("request_id:", handle.request_id)  # with the model ID, all another process needs

        # Poll until the request completes, waiting the Retry-After the server names.
        async for update in handle.iter_events():
            print(update.status, update.queue_position)

        # The provider's own payload, the same value models.run() returns.
        # A request that failed or was cancelled raises the typed Router error here.
        result = await handle.get()

    print(result)

asyncio.run(main())
```

```typescript TypeScript theme={null}
import { comfy } from "@comfyorg/sdk";

// Reads COMFY_API_KEY from the environment.
// Each submit() call mints its own Idempotency-Key and reuses it for automatic retries.
const handle = await comfy.models.submit("fal/crystal-upscaler", {
  image_url: "https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png",
  scale_factor: 2,
});
console.log("requestId:", handle.requestId); // with the model ID, all another process needs

// Poll until the request completes, waiting the Retry-After the server names.
for await (const update of handle.events()) {
  console.log(update.status, update.queuePosition);
}

// The same result models.run() returns. A request that failed or was cancelled rejects here.
const result = await handle.get();

console.log(result.data);
```

```bash cURL theme={null}
# 1. Submit. Router answers 201 with request_id, status_url, response_url and cancel_url.
curl https://api.comfy.org/v2/models/fal/crystal-upscaler/requests \
  -H "X-API-Key: $COMFY_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d "{\"image_url\": \"https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png\", \"scale_factor\": 2}"

# 2. Poll until status is COMPLETED, waiting the Retry-After seconds each response names.
REQUEST_ID="<request_id from the 201 body>"
curl -i https://api.comfy.org/v2/models/fal/crystal-upscaler/requests/$REQUEST_ID/status \
  -H "X-API-Key: $COMFY_API_KEY"

# 3. Collect. 200 with the model's native output, 202 with the status body while it is still running.
curl https://api.comfy.org/v2/models/fal/crystal-upscaler/requests/$REQUEST_ID \
  -H "X-API-Key: $COMFY_API_KEY"
```

## Schema

### Input

**creativity** `number` (default: 0)

How much new detail the model may invent. 0 keeps closest to the input.

Range: `0` to `10`

**image\_url** `string` *required*

URL of the input image (JPEG, PNG, WebP, GIF or AVIF, at most 100 MB).

**output\_format** `string` (default: "jpg")

Output image format: png or jpg.

**scale\_factor** `number` (default: 2)

Factor applied to each side of the input image. fal bills per output megapixel, so the price grows with the square of this value.

Range: `1` to `200`

Generated from the schema Router serves at `GET /v2/models/fal/crystal-upscaler/openapi.json`, the same document it validates a call against before the request reaches the provider.

### Output

**images** `object[]` *required*

The upscaled images.

**images\[].content\_type** `string`

MIME type of the image file.

**images\[].file\_name** `string`

Name of the image file.

**images\[].file\_size** `integer`

Size of the image file in bytes.

**images\[].height** `integer`

Height of the image in pixels. fal sends null.

**images\[].url** `string` *required*

URL of the upscaled image.

**images\[].width** `integer`

Width of the image in pixels. fal sends null.

## Examples

### Input

```json theme={null}
{
  "image_url": "https://storage.googleapis.com/falserverless/gallery/patina-blog-hero-render.png",
  "scale_factor": 2
}
```

### Output

```json theme={null}
{
  "images": [
    {
      "content_type": "image/png",
      "file_name": "upscaled.png",
      "file_size": 1412332,
      "height": null,
      "url": "https://example.invalid/fal/crystal-upscaler/upscaled.png",
      "width": null
    }
  ]
}
```

## Before you ship

The SDKs create an `Idempotency-Key` and reuse it for automatic retries. For manual retries, reuse the original key. Router can hold the connection for up to 10 minutes.

When a request fails, Router sends an `X-Comfy-Error-Type` response header explaining why. A `422` means Router rejected the input before calling the provider, and a `413` means the request body was larger than Router accepts. Download generated assets promptly because [result URLs can expire](https://docs.comfy.org/development/comfy-router/reference.md#result-assets).

Any size limit named in a field description above is the provider's own bound on that field, quoted from the provider's specification. Router applies a separate cap to the whole request body, which base64-encoded media counts against: see [request body size](https://docs.comfy.org/development/comfy-router/limitations.md#request-bodies-are-capped).

This page documents one partner model called through Comfy Router. The same `comfy-sdk` / `@comfyorg/sdk` package also ships a second client, for running a whole ComfyUI workflow graph on Comfy Cloud: `Comfy(api_key=...)` / `new Comfy({ apiKey })`, with `client.workflows`, `client.assets` and `client.jobs`. See [Comfy SDKs](https://docs.comfy.org/development/api-development/sdks.md).

> **[Headers](https://docs.comfy.org/development/comfy-router/headers.md)**
>
> Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.

> **[Using the Router API](https://docs.comfy.org/development/comfy-router/api.md)**
>
> Model discovery, validation errors, retries, and billing.

> **[Limitations](https://docs.comfy.org/development/comfy-router/limitations.md)**
>
> What Router does not do today, and what to use instead.


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