Model Configuration

Fabric uses a centralized model configuration system that determines which AI model handles each operation. This applies across all workflows, not just video generation.

Resolution Order

Models are resolved with a 6-level priority chain. The first match wins:

1. Per-run input override — --input image_model="gemini-2.5-flash-image"
2. Environment variable — FABRIC_IMAGE_MODEL=gemini-2.5-flash-image
3. Project config — ./models.yaml (walks up from cwd)
4. Global config — ~/.fabric/models.yaml
5. Quality profile — --input quality=cheap
6. Built-in defaults

Operations

Each pipeline stage maps to a named operation:

Operation	Default Model	Description
text	gemini-2.5-flash	Script generation, LLM calls
image	gemini-3.1-flash-image-preview	Image generation
image_fast	imagen-4.0-fast-generate-001	Fast image generation (thumbnails, stills)
video	veo-2.0-generate-001	Video generation
broll	fal-ai/veo3.1/fast	B-roll video generation
broll_i2v	fal-ai/kling-video/v3/pro/image-to-video	B-roll image-to-video
keyframe_grid	imagen-4.0-fast-generate-001	Keyframe grid generation
tts	elevenlabs/eleven_multilingual_v2	Text-to-speech
avatar	fal-ai/kling-video/ai-avatar/v2/standard	AI avatar / talking head
lipsync	veed/lipsync	Lip synchronization
music	fal-ai/stable-audio	Background music
transcription	faster-whisper/large-v3	Audio transcription
thumbnail	gemini-3.1-flash-image-preview	Thumbnail generation

Config File

Create models.yaml in your project root or at ~/.fabric/models.yaml:

# Override individual operations
text: gemini-2.5-flash
image: gemini-3.1-flash-image-preview
tts: elevenlabs/eleven_multilingual_v2
broll: fal-ai/veo3.1/fast
keyframe_grid: imagen-4.0-fast-generate-001

# Define custom quality profiles
profiles:
  my-custom:
    tts: fal-ai/kokoro/american-english
    broll: wan:1.3b
    keyframe_grid: sdxl-turbo

Project-level config overrides global config. Top-level keys override profile keys.

Quality Profiles

Profiles bundle model selections for common use cases:

Remote Profiles

cheap

Budget-friendly with acceptable quality. Uses faster/cheaper model variants.

Operation	Model
tts	fal-ai/kokoro/american-english
lipsync	fal-ai/lipsync
keyframe_grid	skip

All other operations use defaults.

premium

Default models across the board. No overrides — uses the built-in defaults.

Local Profiles

local

Full local pipeline with good quality. Requires 8+ GB VRAM.

Operation	Model
text	qwen3:8b (Ollama)
image	sdxl-turbo
video	wan:1.3b
broll	wan:1.3b
tts	kokoro
avatar	wav2lip
lipsync	wav2lip
music	musicgen-small
keyframe_grid	sdxl-turbo
broll_i2v	skip

local-power

Best local quality. Requires more compute.

Operation	Model
text	qwen3:latest (Ollama)
image	flux-schnell
video	wan:1.3b
broll	wan:1.3b
tts	voxtral
avatar	wav2lip
lipsync	wav2lip
music	musicgen-small
keyframe_grid	flux-schnell

local-light

Minimal resource usage. Skips heavy operations.

Operation	Model
text	gemma3:4b (Ollama)
image	sdxl-turbo
video	skip
broll	skip
tts	piper
avatar	skip
lipsync	skip
music	skip
keyframe_grid	skip

Skip Behavior

Setting any operation to "skip" disables it entirely. The pipeline gracefully handles skipped operations — for example, skipping broll means no b-roll videos are generated, and the final composition uses only talking-head segments.

Environment Variables

Every operation maps to a FABRIC_<OPERATION>_MODEL environment variable:

export FABRIC_TEXT_MODEL=gemini-2.5-flash
export FABRIC_IMAGE_MODEL=sdxl-turbo
export FABRIC_TTS_MODEL=kokoro
export FABRIC_BROLL_MODEL=wan:1.3b
export FABRIC_KEYFRAME_GRID_MODEL=imagen-4.0-fast-generate-001

Per-Run Overrides

Override any model for a single run:

fabric run global/ai-shorts \
  --input topic="AI productivity" \
  --input quality=local \
  --input tts_model=elevenlabs/eleven_turbo_v2_5 \
  --input broll_model="fal-ai/veo3.1/fast"

Per-run overrides take highest priority and override both quality profiles and config files.

Using in Custom Workflows

from fabric_workflow_sdk import get_model

# Resolves through the full priority chain
model = get_model(input, "text")           # "gemini-2.5-flash"
model = get_model(input, "broll")          # depends on quality profile
model = get_model(input, "keyframe_grid")  # "skip" or an image model

# With fallback for unknown operations
model = get_model(input, "my_custom_op", fallback="gemini-2.5-flash")