Mynth

The Mynth community adapter calls Flux, Recraft, Gemini, Qwen, Seedream, Wan, and Grok Imagine from generateImage(). Mynth maintains it.

1. Install#

npm i @mynthio/tanstack-ai-adapter @tanstack/ai

pnpm add @mynthio/tanstack-ai-adapter @tanstack/ai

yarn add @mynthio/tanstack-ai-adapter @tanstack/ai

bun add @mynthio/tanstack-ai-adapter @tanstack/ai

The adapter needs @tanstack/ai 0.34 or later.

2. Set the API key#

Make a key in the Mynth API keys dashboard. Then put it in the environment of your server:

MYNTH_API_KEY=mak_...

3. Generate an image#

import { generateImage } from "@tanstack/ai";
import { mynthImage } from "@mynthio/tanstack-ai-adapter";

const result = await generateImage({
  adapter: mynthImage("black-forest-labs/flux.2-dev"),
  prompt: "Editorial product photo of a ceramic mug on a linen tablecloth",
  threadId: "thread-1",
  numberOfImages: 1,
  size: "square",
});

console.log(result.id);
console.log(result.model);
console.log(result.images[0]?.url);

You get a URL to the image in result.images[0]?.url. You pick the Mynth model when you create the adapter.

4. Stream it to your UI#

Return the generation from a route with stream: true:

import {
  generateImage,
  generationParamsFromRequest,
  toServerSentEventsResponse,
} from "@tanstack/ai";
import { mynthImage } from "@mynthio/tanstack-ai-adapter";

export async function POST(request: Request) {
  const { input, threadId, runId } = await generationParamsFromRequest(
    "image",
    request,
  );

  const stream = generateImage({
    adapter: mynthImage("auto"),
    prompt: input.prompt,
    threadId,
    runId,
    numberOfImages: 1,
    stream: true,
  });

  return toServerSentEventsResponse(stream);
}

On the client, use useGenerateImage(). For a full app, see the TanStack Start + Mynth adapter demo.

Image to image#

Models that take image input work with content-part prompts. Mix the instruction text with reference images, for restyles, edits, reference-guided images, and try-on:

import { generateImage } from "@tanstack/ai";
import { mynthImage } from "@mynthio/tanstack-ai-adapter";

const result = await generateImage({
  adapter: mynthImage("black-forest-labs/flux.2-dev"),
  prompt: [
    { type: "text", content: "Restyle this scene as a watercolor painting" },
    {
      type: "image",
      source: { type: "url", value: "https://example.com/photo.jpg" },
    },
  ],
  threadId: "thread-1",
});

The adapter maps the image parts to Mynth inputs:

• Only models in MYNTH_IMAGE_INPUT_MODELS take image parts. An image part for another model is a compile-time error.
• URL sources ({ type: "url", value }) and inline data sources ({ type: "data", value, mimeType }, sent as a data URI) both work.
• The metadata.role of a part maps to the Mynth input intent. TanStack's "character" maps directly. The other roles use the automatic detection of Mynth.
• For the finer Mynth intents (person, garment, pose, style, background, product, object), pass modelOptions.inputs with an explicit as.
• The adapter combines the image parts of the prompt and the entries in modelOptions.inputs. Prompt parts come first.

Share settings across adapters#

Use createMynthImage() to share settings across adapters:

import { generateImage } from "@tanstack/ai";
import { createMynthImage } from "@mynthio/tanstack-ai-adapter";

const mynth = createMynthImage({
  apiKey: process.env.MYNTH_API_KEY!,
  baseUrl: "https://api.mynth.io",
});

const result = await generateImage({
  adapter: mynth("google/gemini-3.1-flash-image"),
  prompt: "A playful paper-cut illustration of a city park in spring",
  threadId: "thread-1",
});

console.log(result.images[0]?.url);

You can still change the settings for one adapter:

import { createMynthImage } from "@mynthio/tanstack-ai-adapter";

const mynth = createMynthImage();

const adapter = mynth("auto", {
  baseUrl: "https://proxy.example.com",
});

• apiKey overrides MYNTH_API_KEY.
• baseUrl is optional. Use it for proxies, tests, or custom deployments.

Models and options#

Models#

The adapter exports a runtime list and a type of the image models:

import { MYNTH_IMAGE_MODELS, type MynthImageModel } from "@mynthio/tanstack-ai-adapter";

const defaultModel: MynthImageModel = "auto";

for (const model of MYNTH_IMAGE_MODELS) {
  console.log(model);
}

• Use the list for model pickers, validation, and to keep the client and the server in sync.
• MYNTH_IMAGE_INPUT_MODELS (and the MynthImageInputModel type) lists the models that take image input.
• The models include auto, Flux, Recraft, Gemini, Qwen, Seedream, Imagine, Wan, Grok Imagine, and try-on models.

The exported list is a fixed snapshot, for type safety. For the live catalog with prices, use the models endpoint.

Model options#

Top-level fields hold the common options: prompt, numberOfImages, and the short size. Put the Mynth options in modelOptions:

import { generateImage } from "@tanstack/ai";
import { mynthImage } from "@mynthio/tanstack-ai-adapter";

const result = await generateImage({
  adapter: mynthImage("recraft/recraft-v4"),
  prompt: "Modern poster design for a jazz festival",
  threadId: "thread-1",
  numberOfImages: 2,
  size: "portrait",
  modelOptions: {
    negativePrompt: "watermark, blurry text",
    magicPrompt: true,
    size: {
      type: "aspect_ratio",
      aspectRatio: "4:5",
      scale: "4k",
    },
    output: {
      format: "png",
      quality: 90,
    },
    rating: true,
    metadata: {
      requestId: "req_123",
    },
  },
});

• negativePrompt maps to negative_prompt. magicPrompt maps to magic_prompt.
• rating sets content rating on the result. contentRating is an alias.
• size overrides the top-level size. Use it for Mynth size objects, with aspect ratios and an optional scale: "4k". The top-level size takes short values such as "auto", "square", or "landscape".
• destination sends the generation to a Mynth destination. It overrides the adapter default and the env default.
• promptStructured expands into prompt, negative_prompt, and magic_prompt. When you set it, its positive overrides the plain prompt.

The result#

The adapter returns the normalized image result of TanStack AI:

• id: the Mynth task id.
• model: the model that Mynth used, or the requested model if Mynth returned none.
• images: only the images that succeeded.
• images[*].revisedPrompt: set when Mynth improves the prompt.

API#

This package has only an image adapter for generateImage(). It has no chat or text adapter.

Advanced#

Models endpoint#

Mynth has a public catalog at https://api.mynth.io/models. It needs no API key, and it has the prices. Use it for a model picker with live prices:

const response = await fetch("https://api.mynth.io/models");
const { data } = await response.json();

for (const model of data) {
  console.log(model.id, model.displayName, model.pricing);
}

Each entry looks about like this:

{
  "id": "black-forest-labs/flux.2-dev",
  "displayName": "FLUX.2 Dev",
  "pricing": {
    "perImage": { "base": "0.01", "4k": "0.04" },
    "perInput": "0.002",
  },
}

With the Mynth SDK, new Mynth().models.list() gives the same data. See the Mynth SDK README and Mynth.