> ## Documentation Index
> Fetch the complete documentation index at: https://dripart-docs-router-model-page-pilot.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Use Flux.1 Kontext with Comfy Router

> Python, TypeScript and cURL snippets for calling Flux.1 Kontext Pro and Kontext Max over HTTP through Comfy Router, plus the request fields and the result shape

API Reference for Flux.1 Kontext. Flux.1 Kontext is Black Forest Labs' instruction-driven image editing model: send an image and a text instruction, get the edited image back with the rest of the scene preserved.

<Note>
  **Comfy Router is not generally available yet.** `POST /v2/models/{provider}/{model}` and its catalog and schema siblings are not serving requests yet: an authenticated call answers `404` today. The snippets on this page document the contract those routes will serve, published ahead of the rollout so your integration is ready to write against.
</Note>

## Quick start

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

Pick the model you want to call. The models share one request and response shape, documented once below.

<Tabs>
  <Tab title="Kontext Pro">
    **Model ID:** `bfl/flux-kontext-pro`

    **Endpoint:** `POST https://api.comfy.org/v2/models/bfl/flux-kontext-pro`

    <CodeGroup>
      ```python Python theme={null}
      import base64

      from comfy_sdk import Comfy

      with open("input.jpg", "rb") as f:
          input_image = base64.b64encode(f.read()).decode()

      # Reads COMFY_API_KEY from the environment. Each call sends a fresh
      # Idempotency-Key and waits up to 10 minutes for the finished result.
      with Comfy() as client:
          result = client.models.run(
              "bfl/flux-kontext-pro",
              {
                  "prompt": "replace the background with a sunlit beach, keep the subject unchanged",
                  "input_image": input_image,
                  "aspect_ratio": "1:1",
              },
          )

      print("image:", result["result"]["sample"])
      ```

      ```typescript TypeScript theme={null}
      import { comfy } from "@comfyorg/sdk";
      import { readFile } from "node:fs/promises";

      const inputImage = (await readFile("input.jpg")).toString("base64");

      // Reads COMFY_API_KEY from the environment. Each call sends a fresh
      // Idempotency-Key and waits up to 10 minutes for the finished result.
      type Result = { result: { sample: string } };
      const { data } = await comfy.models.run<Result>("bfl/flux-kontext-pro", {
        prompt: "replace the background with a sunlit beach, keep the subject unchanged",
        input_image: inputImage,
        aspect_ratio: "1:1",
      });

      console.log("image:", data.result.sample);
      ```

      ```bash cURL theme={null}
      INPUT_IMAGE=$(base64 < input.jpg | tr -d '\n')

      curl https://api.comfy.org/v2/models/bfl/flux-kontext-pro \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"prompt\": \"replace the background with a sunlit beach, keep the subject unchanged\", \"input_image\": \"$INPUT_IMAGE\", \"aspect_ratio\": \"1:1\"}"
      ```
    </CodeGroup>
  </Tab>

  <Tab title="Kontext Max">
    **Model ID:** `bfl/flux-kontext-max`

    **Endpoint:** `POST https://api.comfy.org/v2/models/bfl/flux-kontext-max`

    <CodeGroup>
      ```python Python theme={null}
      import base64

      from comfy_sdk import Comfy

      with open("input.jpg", "rb") as f:
          input_image = base64.b64encode(f.read()).decode()

      # Reads COMFY_API_KEY from the environment. Each call sends a fresh
      # Idempotency-Key and waits up to 10 minutes for the finished result.
      with Comfy() as client:
          result = client.models.run(
              "bfl/flux-kontext-max",
              {
                  "prompt": "replace the background with a sunlit beach, keep the subject unchanged",
                  "input_image": input_image,
                  "aspect_ratio": "1:1",
              },
          )

      print("image:", result["result"]["sample"])
      ```

      ```typescript TypeScript theme={null}
      import { comfy } from "@comfyorg/sdk";
      import { readFile } from "node:fs/promises";

      const inputImage = (await readFile("input.jpg")).toString("base64");

      // Reads COMFY_API_KEY from the environment. Each call sends a fresh
      // Idempotency-Key and waits up to 10 minutes for the finished result.
      type Result = { result: { sample: string } };
      const { data } = await comfy.models.run<Result>("bfl/flux-kontext-max", {
        prompt: "replace the background with a sunlit beach, keep the subject unchanged",
        input_image: inputImage,
        aspect_ratio: "1:1",
      });

      console.log("image:", data.result.sample);
      ```

      ```bash cURL theme={null}
      INPUT_IMAGE=$(base64 < input.jpg | tr -d '\n')

      curl https://api.comfy.org/v2/models/bfl/flux-kontext-max \
        -H "X-API-Key: $COMFY_API_KEY" \
        -H "Idempotency-Key: $(uuidgen)" \
        -H "Content-Type: application/json" \
        -d "{\"prompt\": \"replace the background with a sunlit beach, keep the subject unchanged\", \"input_image\": \"$INPUT_IMAGE\", \"aspect_ratio\": \"1:1\"}"
      ```
    </CodeGroup>
  </Tab>
</Tabs>

## Schema

### Input

*Fields follow Black Forest Labs' published API specification and are checked against it in CI. Router's own schema for this model is not published yet, so requests are forwarded to the provider unvalidated.*

<ParamField body="prompt" type="string" required>
  What to change in the image. Describe the edit, not the whole scene.
</ParamField>

<ParamField body="input_image" type="string">
  The image to edit, base64 encoded or an HTTPS URL. Optional in the schema, but Kontext is an editing model: without it you get text-to-image.
</ParamField>

<ParamField body="aspect_ratio" type="string">
  Output aspect ratio, from `21:9` to `9:21`.
</ParamField>

<ParamField body="seed" type="integer">
  Seed for reproducible results. Omit for random.
</ParamField>

<ParamField body="prompt_upsampling" type="boolean" default="false">
  Rewrite the prompt for richer results. Results are not reproducible when enabled.
</ParamField>

<ParamField body="safety_tolerance" type="integer" default="2">
  Moderation tolerance for inputs and outputs. 0 is strictest.

  Range: `0` to `6`
</ParamField>

<ParamField body="output_format" type="string" default="&#x22;png&#x22;">
  Format of the returned image.

  Possible values: `jpeg`, `png`, `webp`
</ParamField>

<ParamField body="input_image_2" type="string">
  Additional reference image (base64 or HTTPS URL). Experimental multi-reference input.
</ParamField>

<ParamField body="input_image_3" type="string">
  Additional reference image (base64 or HTTPS URL). Experimental multi-reference input.
</ParamField>

<ParamField body="input_image_4" type="string">
  Additional reference image (base64 or HTTPS URL). Experimental multi-reference input.
</ParamField>

### Output

Router returns Black Forest Labs' native response unchanged. The image is at `result.sample`.

<ResponseField name="id" type="string" required>
  BFL task id for this generation.
</ResponseField>

<ResponseField name="status" type="string" required>
  Terminal task status. Router only returns once this is `Ready`.

  Possible values: `Ready`
</ResponseField>

<ResponseField name="result" type="object" required />

<ResponseField name="result.sample" type="string (uri)" required>
  Signed URL of the generated image. Temporary: download it promptly.

  Format: `uri`
</ResponseField>

<ResponseField name="result.prompt" type="string">
  The prompt that was run, after any upsampling.
</ResponseField>

<ResponseField name="result.seed" type="integer">
  Seed used for this generation.
</ResponseField>

## Examples

### Input

```json theme={null}
{
  "prompt": "replace the background with a sunlit beach, keep the subject unchanged",
  "input_image": "<base64 of input.jpg>",
  "aspect_ratio": "1:1"
}
```

### Output

```json theme={null}
{
  "id": "0a1b2c3d-...",
  "status": "Ready",
  "result": {
    "sample": "https://.../out.png",
    "prompt": "replace the background with a sunlit beach, keep the subject unchanged",
    "seed": 1234567890
  }
}
```

The URL is temporary. Download the image promptly if you need to keep it.

## Before you ship

The snippets above are the shortest working call. Three things are the same for every model and are documented once on the [Comfy Router headers](/development/comfy-router/headers) page: send an `Idempotency-Key` on every paid call and reuse it when you retry, expect the connection to be held up to Router's 10 minute deadline, and keep `X-Comfy-Request-Id` from every response. The SDKs do all three for you; the cURL tab does none of them. On failure, `X-Comfy-Error-Type` names the bucket, and a `422` means the body failed the model's schema and was never billed.

<CardGroup cols={3}>
  <Card title="Headers" icon="list" href="/development/comfy-router/headers">
    Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.
  </Card>

  <Card title="Quickstart" icon="rocket" href="/development/comfy-router/quickstart">
    Typed error handling in Python and TypeScript, reading the 422, walking the catalog.
  </Card>

  <Card title="Limitations" icon="triangle-exclamation" href="/development/comfy-router/limitations">
    What Router does not do today, and what to use instead.
  </Card>
</CardGroup>