Image production

Hydracept returns production assets, not raw model outputs.

Search terms teams actually use: sprite sheet AI, transparent PNG generation, pixel art animation frames, inventory icon packs, contact sheet slice, chroma key matte for games.

For image.generate.v1, that means transparent PNGs, cohesive multi-asset sheets, variant sets, and normalized frames you can drop into Unity, Godot, Unreal, or a web pipeline — not a single contact sheet you still crop by hand.

Three production modes

Best for sprite sheets, pixel art animation, character poses, inventory icons, item families, VFX frames, prop packs, and UI glyphs — small-format assets where intra-set cohesion matters more than hero-resolution detail.

Sheet & Slice

Describe a cohesive set once. Hydracept generates a single composition, detects cells, mattes the chroma plate, slices, centers each cell, and returns individual artifacts.

sheet.labels are metadata only — they identify cells in the API response and never appear in the provider prompt or on the generated image.

Example: SNES knight sword-swing sheet (gpt-image-2), matte-processed — hover the homepage demo to compare chroma vs transparency.

Aligned GIF preview built from sliced transparent frames of the same job.

Request

{
  "context": {
    "productId": "my-game",
    "projectId": "cpr_...",
    "environment": "development"
  },
  "input": {
    "prompt": "SNES-era pixel art knight sword swing animation",
    "requestTransparentOutput": true,
    "sheet": {
      "rows": 4,
      "columns": 4,
      "slice": true,
      "animation": { "facing": "right" },
      "labels": [
        "frame-01", "frame-02", "frame-03", "frame-04",
        "frame-05", "frame-06", "frame-07", "frame-08",
        "frame-09", "frame-10", "frame-11", "frame-12",
        "frame-13", "frame-14", "frame-15", "frame-16"
      ],
      "normalize": {
        "width": 256,
        "height": 256,
        "center": true
      }
    }
  },
  "execution": { "executionPreference": "automatic" },
  "idempotencyKey": "sword-swing-sheet-1"
}

Submit as a durable job:

POST /v1/capabilities/image.generate.v1/jobs
Authorization: Bearer <HYDRACEPT_API_KEY>
Content-Type: application/json

Behavior

• sheet.labels optionally name each cell in the API response (frame-01, slash-b, etc.). They are not sent to the provider and must not be drawn on the image.
• sheet.animation requests subtle frame-to-frame motion with a locked facing direction.
• sheet.slice must be true to activate slicing.
• sheet.normalize sets the output canvas per cell (width, height, center).
• variantCount must be 1 when sheet slicing is enabled.
• Hydracept uses provider-native transparency when available and matte normalization when needed.

Output

A succeeded job returns multiple artifacts — one per sliced cell — on the job resource. Download each with:

GET /v1/jobs/{jobId}/artifacts/{artifactId}

Transparent output

For a single asset:

{
  "input": {
    "prompt": "pixel art healing potion icon, isolated",
    "requestTransparentOutput": true
  }
}

Hydracept treats transparency as an output contract: native alpha when the provider supports it, matte normalization and validation otherwise.

Variants

Ask for multiple creative takes in one job:

{
  "input": {
    "prompt": "rusted plasma wrench inventory icon",
    "variantCount": 4,
    "requestTransparentOutput": true
  }
}

Poll the job, compare artifacts, and keep the exact artifactId you want. Provenance stays on the job receipt.

When to use sheets vs variants

Sheets share one canvas — ideal for sprites and icons, not full hero illustrations.

Contract sources

• Capability input schema: GET /v1/capabilities/image.generate.v1 and agent context
• Job lifecycle: Durable Jobs & Receipts
• Public OpenAPI: https://hydracept.com/openapi/hydracept-v1.json