kavel 0.1.0

Generate and edit images from Dart and Flutter with no API key and no account, via the free tier of kavel.ai.

kavel

Generate and edit images from Dart and Flutter with no API key, no account and no card.

dart pub add kavel     # or: flutter pub add kavel

import 'package:kavel/kavel.dart';

final kavel = Kavel();
final img = await kavel.generate(
  'matte black ceramic mug on pale oak, soft window light from the left, shallow depth of field',
  aspectRatio: '16:9',
);
print(img.url); // https://cdn.kavel.ai/uploads/kie/image/....webp

final edited = await kavel.edit(img.url, 'place the mug on a white marble surface');

Every other image package wants a key from OpenAI, fal or Replicate before it runs once — and a key shipped inside a Flutter app is a key anyone can pull out of the binary. This one talks to the free tier of Kavel: a client id the package invents rather than an account you register, so there is no secret to ship.

Why it is shaped this way

• One dependency, http. Works in Flutter on every platform and in plain Dart CLIs.
• An edit lane. edit takes a photo you already have and one sentence describing the change.
• A typed exception. KavelException.kind is an enum — quota means wait or sign in, rejected means reword, signIn means the request is off the free shelf.
• It keeps polling through a dropped connection — a phone switching from Wi-Fi to cellular mid-job does not throw away a generation that is about to run.

Limits, measured against the running service

• The free grant is 15 credits. An image costs 5, an edit costs 15. The package mints a new client id per call, so a loop is not capped at three.
• 30 credits per IP per day sits on top — about six images from one machine — and surfaces as a quota exception.
• Free output is 1K and watermarked; img.watermarked tells you instead of leaving you to guess.
• Free runs queue 25–80 seconds before the model is called, which is why the default deadline is six minutes.
• Video does not run anonymously — the cheapest clip costs more than the grant. The AI video generator has a browser lane for that.

Signing in removes the watermark and opens the full shelf: Nano Banana 2 for up to 14 reference photos, GPT Image 2 for 4K output, Qwen Image 3 when the picture has to contain correctly spelled text, and Seedream 5.0 Pro for photoreal people. Pricing has every tier.

Prompts that work

Name the light, the material and the composition — that moves the result more than adjectives do. For edits, say what changes and the model keeps the rest; it is the same Nano Banana 2 Lite lane behind the AI hairstyle changer and the AI outfit generator. The free AI image generator runs the same engines in a browser, and the showcase has finished output.

Tests

dart test

Offline, with MockClient: argument validation, client id uniqueness, the quota wall (an HTTP 200 recognised only by a field), the sign-in refusal, and polling through a dropped connection.

More languages and recipes: kavel.readthedocs.io.

MIT