fluvie_ai 0.1.3

Author Fluvie videos from natural language: a provider-agnostic LLM client that emits a deterministic VideoSpec.

fluvie_ai

Author Fluvie videos from natural language. You write a prompt; a language model writes a VideoSpec; Fluvie renders it to a real video file. The model runs once, at authoring time. Rendering the spec never calls a model, so the output stays byte-for-byte deterministic.

How it works

1. You give a prompt (and optionally an existing spec to refine).
2. VideoAuthorService sends it to an AiClient together with Fluvie's JSON Schema.
3. The reply is parsed into a VideoSpec. If it does not validate, the service sends the validation error back for up to three repair rounds.
4. buildVideo(spec) turns the spec into a Video you render like any other.

The spec is the artifact. Commit it, diff it, re-render it: the same spec always produces the same frames.

Install

dart pub add fluvie_ai

Quick start

Pick a provider, set its key in the environment, then author a spec and build it:

import 'dart:io';

import 'package:fluvie/fluvie.dart';
import 'package:fluvie_ai/fluvie_ai.dart';

Future<Video> author(String prompt) async {
  final client = aiClientFromEnv(Platform.environment);
  final service = LlmVideoAuthorService(client: client);
  final spec = await service.author(prompt);
  return buildVideo(spec);
}

export FLUVIE_AI_PROVIDER=claude   # claude (default), gemini, mistral, ollama
export ANTHROPIC_API_KEY=sk-...

Providers

Provider	FLUVIE_AI_PROVIDER	API key env	Sees images
Claude (default)	claude	ANTHROPIC_API_KEY	yes
Gemini	gemini	GEMINI_API_KEY	yes
Mistral	mistral	MISTRAL_API_KEY	no
Ollama (local)	ollama	none	no

FLUVIE_AI_MODEL overrides the model. Ollama needs no key and runs against a local server, the easiest way to try this offline. Construct a client directly when you do not want the environment:

final client = ClaudeAiClient(apiKey: myKey);

Refine an existing spec

Pass the current spec as base to change it, and a rendered frame as lastFrame so a multimodal provider (Claude or Gemini) can see what it is editing:

final next = await service.author(
  'make the headline yellow',
  base: current,      // the VideoSpec to change
  lastFrame: preview, // an AiImage of the current render
);

Riverpod

videoAuthorServiceProvider builds the service from aiClientProvider. The client has no default; override it once at the root:

ProviderScope(
  overrides: [
    aiClientProvider.overrideWith((ref) => aiClientFromEnv(Platform.environment)),
  ],
  child: const MyApp(),
);

In tests, override it with FakeAiClient, which replays canned replies with no network.

From the command line

The fluvie_cli renderer wraps all of this end to end:

fluvie generate "a 6s vertical title card, dark gradient, fade-in headline" \
  --out promo.mp4 --spec-out promo.fluvie.json
fluvie edit promo.fluvie.json "make the headline yellow" --out promo.mp4

Documentation

See the Fluvie AI and MCP guide.

License

MIT. See LICENSE.