Stability AI

Overview

Property	Details
Description	Stability AI creates open AI models for image, video, audio, and 3D generation. Known for Stable Diffusion.
Provider Route on LiteLLM	`stability/`
Link to Provider Doc	Stability AI API ↗
Supported Operations	`/images/generations`, `/images/edits`

LiteLLM supports Stability AI Image Generation calls via the Stability AI REST API (not via Bedrock).

API Key

# env variable
os.environ['STABILITY_API_KEY'] = "your-api-key"

Get your API key from the Stability AI Platform.

Image Generation

Usage - LiteLLM Python SDK

from litellm import image_generation
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Stability AI image generation call
response = image_generation(
    model="stability/sd3.5-large",
    prompt="A beautiful sunset over a calm ocean",
)
print(response)

Usage - LiteLLM Proxy Server

1. Setup config.yaml

model_list:
  - model_name: sd3
    litellm_params:
      model: stability/sd3.5-large
      api_key: os.environ/STABILITY_API_KEY
    model_info:
      mode: image_generation

general_settings:
  master_key: os.environ/LITELLM_MASTER_KEY

2. Start the proxy

litellm --config config.yaml

# RUNNING on http://0.0.0.0:4000

3. Test it

curl --location 'http://0.0.0.0:4000/v1/images/generations' \
--header 'Content-Type: application/json' \
--header "Authorization: Bearer $LITELLM_API_KEY" \
--data '{
    "model": "sd3",
    "prompt": "A beautiful sunset over a calm ocean"
}'

Advanced Usage - With Additional Parameters

from litellm import image_generation
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

response = image_generation(
    model="stability/sd3.5-large",
    prompt="A beautiful sunset over a calm ocean",
    size="1792x1024",  # Maps to aspect_ratio 16:9
    negative_prompt="blurry, low quality",  # Stability-specific
    seed=12345,  # For reproducibility
)
print(response)

Supported Parameters

Stability AI supports the following OpenAI-compatible parameters:

Parameter	Type	Description	Example
`size`	string	Image dimensions (mapped to aspect_ratio)	`"1024x1024"`
`n`	integer	Number of images (note: Stability returns 1 per request)	`1`
`response_format`	string	Format of response (`b64_json` only for Stability)	`"b64_json"`

Size to Aspect Ratio Mapping

The size parameter is automatically mapped to Stability's aspect_ratio:

OpenAI Size	Stability Aspect Ratio
`1024x1024`	`1:1`
`1792x1024`	`16:9`
`1024x1792`	`9:16`
`512x512`	`1:1`
`256x256`	`1:1`

Using Stability-Specific Parameters

You can pass parameters that are specific to Stability AI directly in your request:

from litellm import image_generation
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

response = image_generation(
    model="stability/sd3.5-large",
    prompt="A beautiful sunset over a calm ocean",
    # Stability-specific parameters
    negative_prompt="blurry, watermark, text",
    aspect_ratio="16:9",  # Use directly instead of size
    seed=42,
    output_format="png",  # png, jpeg, or webp
)
print(response)

Supported Image Generation Models

Model Name	Function Call	Description
sd3	`image_generation(model="stability/sd3", ...)`	Stable Diffusion 3
sd3-large	`image_generation(model="stability/sd3-large", ...)`	SD3 Large
sd3-large-turbo	`image_generation(model="stability/sd3-large-turbo", ...)`	SD3 Large Turbo (faster)
sd3-medium	`image_generation(model="stability/sd3-medium", ...)`	SD3 Medium
sd3.5-large	`image_generation(model="stability/sd3.5-large", ...)`	SD 3.5 Large (recommended)
sd3.5-large-turbo	`image_generation(model="stability/sd3.5-large-turbo", ...)`	SD 3.5 Large Turbo
sd3.5-medium	`image_generation(model="stability/sd3.5-medium", ...)`	SD 3.5 Medium
stable-image-ultra	`image_generation(model="stability/stable-image-ultra", ...)`	Stable Image Ultra
stable-image-core	`image_generation(model="stability/stable-image-core", ...)`	Stable Image Core

For more details on available models and features, see: https://platform.stability.ai/docs/api-reference

Response Format

Stability AI returns images in base64 format. The response is OpenAI-compatible:

{
    "created": 1234567890,
    "data": [
        {
            "b64_json": "iVBORw0KGgo..."  # Base64 encoded image
        }
    ]
}

Image Editing

Stability AI supports various image editing operations including inpainting, upscaling, outpainting, background removal, and more.

Optional Parameters

Important: Different Stability models have different parameter requirements:

Some models don't require a prompt (e.g., upscaling, background removal)
The outpaint model takes numeric left and right pixel counts. LiteLLM does not forward up or down, the fields Stability uses for vertical outpainting, so only horizontal outpainting works through stability/ today
Style Transfer is not reachable through stability/ today: stability/style-transfer resolves to the Style Guide endpoint (/v2beta/stable-image/control/style) and the input is always sent as image, while Stability's Style Transfer endpoint requires init_image

Usage - LiteLLM Python SDK

Inpainting (Edit with Mask)

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Inpainting - edit specific areas using a mask
response = image_edit(
    model="stability/inpaint",
    image=open("original_image.png", "rb"),
    mask=open("mask_image.png", "rb"), 
    prompt="Add a beautiful sunset in the masked area",
    size="1024x1024",
)
print(response)

Image Upscaling

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Conservative upscaling - preserves details
response = image_edit(
    model="stability/conservative",
    image=open("low_res_image.png", "rb"),
    prompt="Upscale this image while preserving details",
)

# Creative upscaling - adds creative details
response = image_edit(
    model="stability/creative",
    image=open("low_res_image.png", "rb"),
    prompt="Upscale and enhance with creative details",
    creativity=0.3,  # 0-0.35, higher = more creative
)

# Fast upscaling - quick upscaling (no prompt needed)
response = image_edit(
    model="stability/fast",
    image=open("low_res_image.png", "rb"),
    # No prompt required for fast upscale
)
print(response)

Image Outpainting

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Extend image beyond its borders
response = image_edit(
    model="stability/outpaint",
    image=open("original_image.png", "rb"),
    prompt="Extend this landscape with mountains",
    left=100,   # Pixels to extend on the left
    right=100,  # Pixels to extend on the right
)
print(response)

Background Removal

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Remove background from image
response = image_edit(
    model="stability/remove-background",
    image=open("portrait.png", "rb"),
    # No prompt required for fast upscale
)
print(response)

Search and Replace

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Search and replace objects in image
response = image_edit(
    model="stability/search-and-replace",
    image=open("scene.png", "rb"),
    prompt="A red sports car",
    search_prompt="blue sedan",  # What to replace
)

# Search and recolor
response = image_edit(
    model="stability/search-and-recolor",
    image=open("scene.png", "rb"),
    prompt="Make it golden yellow",
    select_prompt="the car",  # What to recolor
)
print(response)

Image Control (Sketch/Structure)

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Control with sketch
response = image_edit(
    model="stability/sketch",
    image=open("sketch.png", "rb"),
    prompt="Turn this sketch into a realistic photo",
    control_strength=0.7,  # 0-1, higher = more control
)

# Control with structure
response = image_edit(
    model="stability/structure",
    image=open("structure_reference.png", "rb"),
    prompt="Generate image following this structure",
    control_strength=0.7,
)
print(response)

Erase Objects

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Erase objects from image
response = image_edit(
    model="stability/erase",
    image=open("scene.png", "rb"),
    mask=open("object_mask.png", "rb"),  # Mask the object to erase
    # No prompt needed
)
print(response)

Style Guide

from litellm import image_edit
import os

os.environ['STABILITY_API_KEY'] = "your-api-key"

# Generate a new image in the style of a reference image
response = image_edit(
    model="stability/style",
    image=open("style_reference.png", "rb"),  # Style reference
    prompt="A lighthouse on a cliff at sunset",
)

print(response)

Supported Image Edit Models

Model Name	Function Call	Description
inpaint	`image_edit(model="stability/inpaint", ...)`	Inpainting with mask
conservative	`image_edit(model="stability/conservative", ...)`	Conservative upscaling
creative	`image_edit(model="stability/creative", ...)`	Creative upscaling
fast	`image_edit(model="stability/fast", ...)`	Fast upscaling
outpaint	`image_edit(model="stability/outpaint", ...)`	Extend image borders
remove-background	`image_edit(model="stability/remove-background", ...)`	Remove background
search-and-replace	`image_edit(model="stability/search-and-replace", ...)`	Search and replace objects
search-and-recolor	`image_edit(model="stability/search-and-recolor", ...)`	Search and recolor
sketch	`image_edit(model="stability/sketch", ...)`	Control with sketch
structure	`image_edit(model="stability/structure", ...)`	Control with structure
erase	`image_edit(model="stability/erase", ...)`	Erase objects
style	`image_edit(model="stability/style", ...)`	Apply style guide

Usage - LiteLLM Proxy Server

1. Setup config.yaml

model_list:
  - model_name: stability-inpaint
    litellm_params:
      model: stability/inpaint
      api_key: os.environ/STABILITY_API_KEY
    model_info:
      mode: image_edit

  - model_name: stability-upscale
    litellm_params:
      model: stability/conservative
      api_key: os.environ/STABILITY_API_KEY
    model_info:
      mode: image_edit

general_settings:
  master_key: os.environ/LITELLM_MASTER_KEY

2. Start the proxy

litellm --config config.yaml

# RUNNING on http://0.0.0.0:4000

3. Test it

curl -X POST "http://0.0.0.0:4000/v1/images/edits" \
  -H "Authorization: Bearer $LITELLM_API_KEY" \
  -F "model=stability-inpaint" \
  -F "image=@original_image.png" \
  -F "mask=@mask_image.png" \
  -F "prompt=Add a beautiful garden in the masked area"

AWS Bedrock (Stability)

LiteLLM also supports Stability AI models via AWS Bedrock. This is useful if you're already using AWS infrastructure.

Usage - Bedrock Stability

from litellm import image_edit
import os

# Set AWS credentials
os.environ["AWS_ACCESS_KEY_ID"] = "your-access-key"
os.environ["AWS_SECRET_ACCESS_KEY"] = "your-secret-key"
os.environ["AWS_REGION_NAME"] = "us-east-1"

# Bedrock Stability inpainting
response = image_edit(
    model="bedrock/us.stability.stable-image-inpaint-v1:0",
    image=open("original_image.png", "rb"),
    mask=open("mask_image.png", "rb"),
    prompt="Add flowers in the masked area",
)
print(response)

# Fast upscale without prompt
response = image_edit(
    model="bedrock/stability.stable-fast-upscale-v1:0",
    image=open("low_res_image.png", "rb"),
)

# Outpaint with numeric parameters
response = image_edit(
    model="bedrock/stability.stable-outpaint-v1:0",
    image=open("original_image.png", "rb"),
    left=100,   # Automatically converted to int
    right=100,
    up=50,
    down=50,
)

print(response)

Supported Bedrock Stability Models

All Stability AI image edit models are available via Bedrock with the bedrock/ prefix:

Direct API Model	Bedrock Model	Description
stability/inpaint	bedrock/us.stability.stable-image-inpaint-v1:0	Inpainting
stability/conservative	bedrock/stability.stable-conservative-upscale-v1:0	Conservative upscaling
stability/creative	bedrock/stability.stable-creative-upscale-v1:0	Creative upscaling
stability/fast	bedrock/stability.stable-fast-upscale-v1:0	Fast upscaling
stability/outpaint	bedrock/stability.stable-outpaint-v1:0	Outpainting
stability/remove-background	bedrock/stability.stable-image-remove-background-v1:0	Remove background
stability/search-and-replace	bedrock/stability.stable-image-search-replace-v1:0	Search and replace
stability/search-and-recolor	bedrock/stability.stable-image-search-recolor-v1:0	Search and recolor
stability/sketch	bedrock/stability.stable-image-control-sketch-v1:0	Control with sketch
stability/structure	bedrock/stability.stable-image-control-structure-v1:0	Control with structure
stability/erase	bedrock/stability.stable-image-erase-object-v1:0	Erase objects

Note: Bedrock model IDs may use us.stability.* or stability.* prefix depending on the region and model.

Comparing Routes

LiteLLM supports Stability AI models via two routes:

Route	Provider	Use Case	Image Generation	Image Editing
`stability/`	Stability AI Direct API	Direct access, all latest models	✅	✅
`bedrock/stability.*`	AWS Bedrock	AWS integration, enterprise features	✅	✅

Use stability/ for direct API access. Use bedrock/stability.* if you're already using AWS Bedrock.

Overview​

API Key​

Image Generation​

Usage - LiteLLM Python SDK​

Usage - LiteLLM Proxy Server​

1. Setup config.yaml​

2. Start the proxy​

3. Test it​

Advanced Usage - With Additional Parameters​

Supported Parameters​

Size to Aspect Ratio Mapping​

Using Stability-Specific Parameters​

Supported Image Generation Models​

Response Format​

Image Editing​

Usage - LiteLLM Python SDK​

Inpainting (Edit with Mask)​

Image Upscaling​

Image Outpainting​

Background Removal​

Search and Replace​

Image Control (Sketch/Structure)​

Erase Objects​

Style Guide​

Supported Image Edit Models​

Usage - LiteLLM Proxy Server​

1. Setup config.yaml​

2. Start the proxy​

3. Test it​

AWS Bedrock (Stability)​

Usage - Bedrock Stability​

Supported Bedrock Stability Models​

Comparing Routes​

Overview

API Key

Image Generation

Usage - LiteLLM Python SDK

Usage - LiteLLM Proxy Server

1. Setup config.yaml

2. Start the proxy

3. Test it

Advanced Usage - With Additional Parameters

Supported Parameters

Size to Aspect Ratio Mapping

Using Stability-Specific Parameters

Supported Image Generation Models

Response Format

Image Editing

Usage - LiteLLM Python SDK

Inpainting (Edit with Mask)

Image Upscaling

Image Outpainting

Background Removal

Search and Replace

Image Control (Sketch/Structure)

Erase Objects

Style Guide

Supported Image Edit Models

Usage - LiteLLM Proxy Server

1. Setup config.yaml

2. Start the proxy

3. Test it

AWS Bedrock (Stability)

Usage - Bedrock Stability

Supported Bedrock Stability Models

Comparing Routes