# Theo · Image Generation

> Theo's image stack is a priority-ordered provider chain with intelligent prompt enhancement and an honest fallback contract. Every generated image is persisted, branded with the engine that actually served the request, and exposed under one Theo-branded model surface.

Source of truth: https://hitheo.ai. Last updated: 2026-05-24.

## At a glance
- Engines (branded): Theo Turbo (fast), Theo Core (general), Theo Ink (vector + type), Theo Lucid (clean), Theo Chroma (saturated), Theo Photo (photo-real), Theo Studio (high-detail), Theo Design (illustrative), Theo Type (typography-aware).
- Prompt enhancement: each request is rewritten by a fast reasoning model into a directorial prompt before generation.
- Honest fallback: when the chain falls through from the requested engine to a fallback, the artifact, the tool trace, and the response label all reflect the engine that actually served the request.
- Persistent storage: every generated image is uploaded to object storage. Responses include a permanent URL.
- Aspect ratios: square, portrait, landscape, wide. Each engine maps to its allowed sizes automatically.

## Editing (image-to-image)
- Engines: Theo Ink Edit, Theo Studio Edit (subject-preserving), Theo Dream Edit, Theo Dream Lite Edit (Stealth surface).
- The routing engine automatically promotes "edit" intents on a prior image to the matching edit engine so prior-subject continuity is preserved.
- Edits accept an image_url and optional strength / mask parameters.

## API
- Primary endpoint: POST /api/v1/completions with mode "image" or with an image-intent prompt that the routing engine promotes.
- Body fields: prompt (required), style (optional), aspect (optional, defaults square), engine (optional pin), num_images (optional).
- Response: streaming SSE with artifact events (modelId, providerId, url, dimensions) or non-streaming JSON with an artifacts[] array.

## Selecting an engine
- For speed: Theo Turbo. Sub-3-second wall time on a clean prompt.
- For photo-real: Theo Photo. The highest-fidelity tier for product, portrait, and editorial work.
- For typography or signage: Theo Type. Reads the prompt for typographic intent and chooses a layout-aware engine.
- For vector / illustration: Theo Ink or Theo Design.
- For high detail with iterative edits: Theo Studio.
- For unfiltered / NSFW: Theo Dream / Theo Dream Lite (Stealth surface). See https://hitheo.ai/llms/stealth.txt.

## Safety
- Image sanitizer strips EXIF / IPTC / XMP / ICC metadata before any image touches an AI engine. DICOM-aware: re-encodes DICOM payloads as PNG to strip PHI. See https://hitheo.ai/llms/guardrails.txt.
- Bot challenge and abuse heuristics apply to public embed image surfaces.

## Related machine-readable files
- https://hitheo.ai/llms.txt — full index of every Theo machine-readable file.
- https://hitheo.ai/llms-full.txt — long-form knowledge bundle (single fetch).
- https://hitheo.ai/humans.txt — team and open-source credits.
- https://hitheo.ai/lawyers.txt — trademark notice and legal contact.
- https://hitheo.ai/.well-known/security.txt — security disclosure contact.