Extend images beyond their borders with Stability AI's outpaint endpoint, paid per call via MPP.
What it does
This endpoint provides access to Stability AI's Outpaint capability through the Locus MPP (Micropayment Protocol) gateway. Outpainting expands an image beyond its original boundaries by generating new content that seamlessly blends with the existing image. You supply a source image and specify how many pixels to add on each side (left, right, up, down), with an optional text prompt to guide the generated content and a creativity parameter to control how inventive the fill is.
The endpoint is part of a broader Stability AI service suite exposed via Locus MPP that includes image generation (Ultra, Core, SD3), editing (erase, inpaint, search-and-replace, search-and-recolor), background removal and replacement, upscaling, sketch-to-image, style transfer, 3D model generation, and audio generation. Each endpoint is individually priced and charged per call using the Tempo settlement method on pathUSD. The outpaint endpoint costs $0.046 per call (46,000 base units at 6 decimals). Output formats supported are JPEG, PNG, and WebP.
Note that the probe did not receive a 402 challenge on HEAD/GET — this is expected because the endpoint only accepts POST requests. The OpenAPI spec is comprehensive, listing full request schemas and payment metadata for all sibling endpoints. The currency token address is 0x20c000000000000000000000b9537d11c60e8b50 (pathUSD on Tempo).
Capabilities
Use cases
- —Expanding product photos to fit wider banner or social media aspect ratios
- —Extending landscape or architectural images to create panoramic compositions
- —Adding contextual surroundings to tightly cropped portraits or objects
- —Preparing images for print layouts that require bleed area beyond the original frame
- —Automated batch processing of image assets that need uniform dimensions
Fit
Best for
- —AI agents that need programmatic image canvas extension with pay-per-call pricing
- —Workflows requiring seamless outward expansion of existing images
- —Developers who want Stability AI access without managing API keys or subscriptions
- —Applications needing prompt-guided creative fill around image borders
Not for
- —High-volume batch jobs where subscription pricing would be more cost-effective
- —Use cases requiring real-time sub-second latency (async result polling may be needed)
- —Generating images from scratch with no source image (use generate-ultra or generate-core instead)
Quick start
curl -X POST https://stability-ai.mpp.paywithlocus.com/stability-ai/outpaint \
-H "Content-Type: application/json" \
-H "Authorization: Bearer <MPP_TOKEN>" \
-d '{
"image": "<base64-encoded-image>",
"left": 200,
"right": 200,
"prompt": "lush green forest extending into the distance",
"output_format": "png"
}'Example
Request
{
"up": 0,
"down": 128,
"left": 256,
"seed": 42,
"image": "<base64-encoded-image>",
"right": 256,
"prompt": "continuation of a sunny beach scene with clear blue sky",
"creativity": 0.5,
"output_format": "jpeg"
}Endpoint
Quality
Full OpenAPI schema with detailed request parameters and payment metadata is available. The specific outpaint endpoint was not directly probed with POST so no 402 challenge was captured, but the OpenAPI spec clearly documents it. No response schema or example responses are provided. Pricing is clearly derivable from the payment info.
Warnings
- —No 402 challenge was captured for this endpoint — the probe used HEAD/GET but the endpoint only accepts POST
- —No response schema is documented; the response format (image data vs. async job ID) is not specified in the OpenAPI
- —The currency token (0x20c000000000000000000000b9537d11c60e8b50) is inferred to be pathUSD with 6 decimals based on sibling endpoint pricing patterns, but this is not explicitly confirmed in the probe data
Citations
- —The outpaint endpoint costs 46,000 base units in pathUSD per call via Tempo settlementhttps://stability-ai.mpp.paywithlocus.com
- —The endpoint accepts image, left, right, up, down, prompt, creativity, output_format, and seed parameters with image being requiredhttps://stability-ai.mpp.paywithlocus.com
- —Stability AI API reference is available at platform.stability.aihttps://platform.stability.ai/docs/api-reference
- —LLM-readable docs are available at beta.paywithlocus.com/mpp/stability-ai.mdhttps://beta.paywithlocus.com/mpp/stability-ai.md