# Gemini Prompts > This skill should be used when the user asks to "write a prompt for image generation", "design a generation prompt", "create a sprite prompt", "compose a Gemini prompt", "structure a prompt for game art", or otherwise needs to construct prompts for the gemini-creative-plugin. Covers the Identity Guide 5-line pattern, isolation suffix template for asset extraction, narrative-vs-keyword rules, and Do/Avoid prompting rules. Domain-specific prompt structures (sprites, environments, UI, icons, web) live in references/domain-structures.md. Use when this capability is needed. - Skill: `tomevault-io/gemini-prompts` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/gemini-prompts` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/gemini-prompts/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/gemini-prompts --- # Gemini Prompting Guide Write effective prompts for Gemini image generation. The core principle from Google: **describe the scene narratively, don't just list keywords.** ## Universal Prompt Structure ``` [Subject] + [Composition] + [Action/State] + [Location/Context] + [Style] + [Technical specs] ``` **Bad:** `knight pixel art game` **Good:** `2D pixel art knight character in idle stance, front-facing, blue tabard with gold lion emblem, silver plate armor, white background, 16x16 pixel grid, game sprite sheet style` For per-domain prompt structures (sprites, environments, characters, UI, icons, web sections), see `references/domain-structures.md`. --- ## The Identity Guide Pattern (validated 2026-05-12) For series work — sprite sets, evolution-chain atlases, mockup screens, item packs — pin a byte-identical identity guide block at the top of every call in the series. The variant prompt then describes only what differs. **Five-line structure:** ``` Identity: [IP name, what the world is, who plays] Form: [3D/2D, geometry style, surface character, proportions] Camera: [angle, lens, key/fill lighting setup] Palette: [Name #HEX, Name #HEX, ...] Materials: [textures, finishes, special-state effects] ``` **Why it works:** the model treats the guide as canonical context for *what world this is in*. The variant prompt only has to answer "what specific item this time?". Cross-call consistency comes from the guide being **literally the same text** every time, not from passing image references. **The Identity line is load-bearing.** Give it a specific fictional project name — "Hollowfest Manor," "Crystal Caverns," "Tideglass Cove," whatever yours is. Real or invented; both work. Don't settle for category descriptors ("a Halloween merge-2 game") when an IP name is available. The model's prior for fictional-IP-cohesion activates when there's a name to anchor on — empirically a stronger consistency anchor than abstract world descriptors alone. Adapted from Dori Adar's original framing of the pattern. **When to use:** - Multiple thematic asset variants in the same world (3D items, evolution chains, UI screens with shared brand) - Cross-modality projects where the same IP needs to render across 3D items AND flat-vector UI **When NOT to use:** - Single-subject repetition across poses → use the Hybrid Workflow with image refs instead (see `gemini-workflows` skill) - Unrelated one-off images → the guide is overhead with no payoff Validated across a 27-image A/B/C experiment + 6-deliverable production pass. --- ## Prompting Rules **Do:** - Use narrative descriptions ("a cozy coffee shop with warm amber lighting" not "coffee shop warm") - Name every distinctive visual detail to preserve across iterations - Specify style explicitly (photorealistic, watercolor, pixel art, flat vector, 3D render) - Describe lighting and mood ("dramatic rim lighting", "soft diffused daylight") - Use positive framing ("clean white background" not "no clutter") - For series work: pin a byte-identical Identity Guide block at the top of every call (see above) - For dense-label or atlas-shaped prompts: append the negative-instruction suffix verbatim — `"Do not render color swatches, hex codes, or palette legends anywhere in the image."` Validated at 5/6 (production pass) + 2/2 (#14b A/B) ≈ 88% suppression. **Avoid:** - Pure keyword lists ("cat space neon cyberpunk") - Vague quality requests ("make it better", "improve the details") - Assuming Gemini will maintain details that weren't described — if it's important, name it - Re-describing the same style with different words across calls in a series — empirically causes consistency drift. Pin the guide verbatim instead. - "For game asset extraction" / "for reference" framings inside the prompt — observed correlating with the palette-legend rendering bug; phrase in product terms instead ("for a Halloween merge-2 game", not "for asset extraction") --- ## Isolation Suffix for Asset Extraction When generating individual items destined to be cut out and used as standalone sprites/icons, append this hard-rules block verbatim: ``` Hard rules — must be followed exactly: - Single object centered in frame, fully visible with breathing room from edges - Pure white #FFFFFF uniform background, no gradient or vignette - NO cast shadow, NO drop shadow, NO ground shadow — the item floats on the flat background - NO color swatches, NO hex codes, NO palette legends, NO color charts anywhere - NO UI elements, NO text, NO labels, NO decorations beyond what is described ``` Production-validated across 33 generations: ~100% shadow compliance, ~95% swatch suppression. The output is directly consumable by a chroma-key extraction pipeline. For white-ish subjects (ghosts, white skulls), fall back to semantic segmentation (rembg). See the `gemini-game-assets` skill § Single-Isolated-Subject Extraction Pattern. --- ## Iteration Strategy 1. **First pass:** Generate with a full detailed prompt 2. **If detail is wrong:** Use `continue_editing` with a targeted correction ("change the helmet visor to horizontal slats") 3. **If overall composition is wrong:** Start fresh with `generate_image` — editing rarely fixes fundamental composition issues 4. **If style drifted:** Pass the original image + style description, not just the correction --- ## Text in Images Gemini handles text in images but requires precision: - State the exact text: `text reads "PLAY" in bold white letters` - Specify font style and placement: `centered at bottom, sans-serif, all caps` - Keep it short — long text strings have higher error rates - Verify with Read tool — text errors are common (e.g., "SWIM" → "SVIM") --- ## Additional Resources ### Reference Files - **`references/domain-structures.md`** — Per-domain prompt structures: game sprites, game environments, character concepts, UI/mobile mockups, icon sets, web sections. --- > Source: [2901were/gemini-creative-plugin](https://github.com/2901were/gemini-creative-plugin) — distributed by [TomeVault](https://tomevault.io).