image-poster
nexu-io/open-design · Agent Skill
Generates images for posters, key art, and illustrations, utilizing various selectable models.
Jump to install ↓Overview
| Publisher | |
|---|---|
| Repository | nexu-io/open-design ↗ |
| Skill folder | image-poster |
| Stars | 95,886 |
| Forks | 11,122 |
| Bundled files | 2 |
| License | Apache-2.0 |
| Last updated | September 13, 2026 |
| Links | Skill source ↗ · Repository ↗ |
Mozgi check
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Installation
A skill is a folder with a SKILL.md file. Pick your agent and run the commands in a terminal (macOS, Linux or Git Bash on Windows) from your project root.
Copy the prompt into Claude, Codex or another assistant: it will review the skill and install it for you.
Install the “image-poster” skill from mozgi.io (https://mozgi.io/skills/image-poster/) for me. 1. Download the archive: https://mozgi.io/skills/image-poster/download If it fails, take the skill folder from the source: https://github.com/nexu-io/open-design/tree/main/design-templates/image-poster 2. Read SKILL.md and the other files. Check the skill is safe: no hidden commands, no sending data elsewhere, no scripts doing something other than described. If anything looks suspicious, stop and tell me. 3. Put the “image-poster” folder into your agent's skills folder: .claude/skills/ for Claude Code, .agents/skills/ for Codex, .cursor/skills/ for Cursor, .gemini/skills/ for Gemini CLI. Inside the project if we are in one, otherwise in the home folder (~/.claude/skills/ etc.). 4. Make sure <skills folder>/image-poster/SKILL.md exists. 5. Briefly tell me what this skill does and offer to try it on my task. If you cannot do a step yourself, tell me what to click or type.
git clone --depth 1 --branch main https://github.com/nexu-io/open-design.git /tmp/open-design mkdir -p .claude/skills cp -r /tmp/open-design/design-templates/image-poster .claude/skills/image-poster
Restart Claude Code — the skill appears in the list; call it manually with /image-poster. For all projects use ~/.claude/skills.
git clone --depth 1 --branch main https://github.com/nexu-io/open-design.git /tmp/open-design mkdir -p .agents/skills cp -r /tmp/open-design/design-templates/image-poster .agents/skills/image-poster
Codex looks for skills in .agents/skills from the current folder up to the repo root; call one with /skills or $image-poster. For all projects use ~/.agents/skills.
git clone --depth 1 --branch main https://github.com/nexu-io/open-design.git /tmp/open-design mkdir -p .cursor/skills cp -r /tmp/open-design/design-templates/image-poster .cursor/skills/image-poster
Cursor picks the skill up on start; call it with “/” in Agent chat. Cursor also reads .claude/skills and .agents/skills. For all projects use ~/.cursor/skills.
git clone --depth 1 --branch main https://github.com/nexu-io/open-design.git /tmp/open-design mkdir -p .gemini/skills cp -r /tmp/open-design/design-templates/image-poster .gemini/skills/image-poster
Gemini CLI offers to activate the skill when a task matches — you approve it. For all projects use ~/.gemini/skills.
Read SKILL.md and any companion files before deciding whether to install. Click a file to preview it.
SKILL.md contents
Original author text · read-onlyImage Poster Skill
Produce one finished image asset per turn unless the user asks for
variations. Image generation rewards a tight, structured prompt — your
job is to assemble that prompt from the user's brief, then dispatch.
Resource map
image-poster/
├── SKILL.md ← you're reading this
└── example.html ← what the resulting card looks like in Examples
Workflow
Step 0 — Read the project metadata
The active project carries imageModel, imageAspect, and (optional)
imageStyle notes. Use them as the upstream model + canvas + style
anchor. When a value is not provided, infer a safe default from the brief and
media contract. Ask only when the choice would materially change the requested
result and no safe default can be inferred.
Step 1 — Compose the prompt
Plan in this exact order before calling any tool:
1. Subject + composition — what is in the frame, where, at what
scale; eye-line and crop.
2. Lighting + mood — natural / studio / moody; warm / cool; key
plus rim plus fill; time of day if outdoor.
3. Palette + textures — hex anchors when the user gave a brand
palette; otherwise a 3-word mood tag (e.g. "muted ochre + ink").
4. Camera / lens — only if the user wants photographic realism
("85mm portrait, shallow DOF") or a specific film stock.
5. What to avoid — common AI-slop patterns ("no extra fingers, no
warped text, no logo placeholders").
Step 2 — Dispatch via the media contract
Use the unified dispatcher — do not call upstream provider APIs by
hand. Run from your shell tool:
"$OD_NODE_BIN" "$OD_BIN" media generate \
--project "$OD_PROJECT_ID" \
--surface image \
--model "<imageModel from metadata>" \
--aspect "<imageAspect from metadata>" \
--output "<short-descriptive-name>.png" \
--prompt "<the full assembled prompt from Step 1>"
The command prints one line of JSON: {"file": {"name": "...", ...}}.
The daemon writes the bytes into the project folder; the FileViewer
picks it up automatically.
Step 3 — Hand off
Reply with a one-paragraph summary of the prompt you used and the
filename returned by the dispatcher (e.g. *I generated hero-poster.png
with gpt-image-2 at 1:1.*). Do not emit an <artifact> tag.
Hard rules
- One image per turn unless asked for variations.
- Honor
imageAspectexactly — the upstream cost is the same; matching
the aspect avoids a re-render.
- No filler typography in the image itself unless the user asked for
in-frame text. Real copy beats lorem.
- Save every render — never describe an image without producing the
file. The user expects something to open in the file viewer.
Frequently asked questions
What does the image-poster skill do?
Generates images for posters, key art, and illustrations, utilizing various selectable models.
How do I install image-poster?
Open the “Installation” block on this page and pick your agent — Claude Code, Codex, Cursor or Gemini CLI — for ready-made commands that copy the skill folder to the right place. Or copy the prompt from the “Via assistant” tab and let the assistant review and install the skill.
Which AI models work with image-poster?
Skills are plain Markdown instructions (the Agent Skills format), so image-poster works with any agent that reads SKILL.md: Claude Code, Codex, Cursor, Gemini CLI, GitHub Copilot, OpenCode and more. The model loads the instructions only when a task matches the skill's description.
Is image-poster free?
The skill is published openly by nexu-io under the Apache-2.0 license. The skill itself costs nothing — you only pay your AI provider for the tokens you use.
Is it safe to install skills?
A skill is a set of instructions your agent will follow, so read SKILL.md and its companion files before installing. Scripts in the skill folder only run if your agent runs them — keep an eye on what it does and do not grant unnecessary permissions.
How is a skill different from an MCP server or a plugin?
An MCP server or plugin gives the model new tools — code that runs and returns a result. A skill gives it knowledge and process: how to approach a task, which steps to follow and what good output looks like. It needs no server or API key.