Structure-guided image generation via Stability AI, pay-per-call over MPP/Tempo.
What it does
This endpoint provides Stability AI's Structure control capability through the Locus MPP (Micropayment Protocol) gateway. It generates images guided by a structural reference image — preserving the spatial layout, edges, and composition of the input while rendering new content described by a text prompt. You control structure adherence via a `control_strength` parameter (0–1, default 0.7), and can specify negative prompts, output format (jpeg/png/webp), aspect ratio, and a random seed for reproducibility.
The Structure endpoint is one of over 20 Stability AI capabilities exposed through this MPP service, which also includes text-to-image generation (Ultra, Core, SD3), editing tools (erase, inpaint, outpaint, search-and-replace, search-and-recolor), background removal and replacement, upscaling (fast, conservative, creative), sketch-to-image, style transfer, image-to-3D (Stable Fast 3D, Stable Point Aware 3D), and audio generation/editing. Each endpoint is individually priced and settled via the Tempo L2 payment method using pathUSD.
The Structure endpoint costs $0.057 per call (57,000 base units of a 6-decimal stablecoin). Payment is handled automatically via the MPP 402 challenge-response flow — no API key or subscription required. The endpoint accepts POST requests with a JSON body containing the required `image` (structure reference) and `prompt` fields. Note that the probe returned 404 on HEAD/GET, which is expected since this is a POST-only endpoint.
Capabilities
Use cases
- —Generating new images that preserve the spatial layout and composition of an existing reference image
- —Restyling architectural or product photos while maintaining structural integrity
- —Creating variations of a scene with consistent geometry but different visual themes
- —Automating content creation pipelines that need structure-consistent image outputs
- —Building agent workflows that transform reference images into styled outputs programmatically
Fit
Best for
- —Agents needing structure-preserving image generation without API key management
- —Pay-per-call image generation with no subscription commitment
- —Workflows requiring consistent spatial composition across style variations
- —Developers integrating Stability AI capabilities via micropayment protocols
Not for
- —Free-form text-to-image generation without a reference image (use Generate Ultra/Core/SD3 instead)
- —High-volume batch processing where subscription pricing would be more economical
- —Use cases requiring real-time streaming image generation
Quick start
curl -X POST https://stability-ai.mpp.paywithlocus.com/stability-ai/structure \
-H "Content-Type: application/json" \
-d '{
"image": "<base64-encoded-reference-image>",
"prompt": "A futuristic cityscape at sunset",
"control_strength": 0.7,
"output_format": "png"
}'Example
Request
{
"seed": 42,
"image": "<base64-encoded-structure-reference-image>",
"prompt": "A futuristic cityscape at sunset, photorealistic",
"output_format": "png",
"negative_prompt": "blurry, low quality",
"control_strength": 0.7
}Endpoint
Quality
Full OpenAPI schema with detailed request parameters and pricing is available. However, the probe returned 404 because HEAD/GET were tried on a POST-only endpoint, so liveness via the 402 challenge was not directly confirmed. No response schema or example responses are documented. The crawl pages all returned generic 404 JSON, providing no additional documentation beyond the OpenAPI spec.
Warnings
- —Probe returned 404 on HEAD and GET — endpoint is POST-only; liveness via 402 challenge not directly confirmed
- —No response schema documented — output format and structure of successful responses are unknown
- —Currency address 0x20c000000000000000000000b9537d11c60e8b50 assumed to be a 6-decimal stablecoin (pathUSD); if decimals differ, the stated price of $0.057 would be incorrect
- —Audio endpoint pricing uses null amounts with description-based pricing, suggesting dynamic pricing for some sibling endpoints
Citations
- —Structure endpoint costs 57,000 base units via Tempo settlementhttps://stability-ai.mpp.paywithlocus.com
- —Required fields are image and prompt; optional fields include control_strength, negative_prompt, output_format, seedhttps://stability-ai.mpp.paywithlocus.com
- —API reference available at platform.stability.aihttps://platform.stability.ai/docs/api-reference
- —LLM-readable docs available at beta.paywithlocus.comhttps://beta.paywithlocus.com/mpp/stability-ai.md