How to Turn a Napkin Sketch into Concept Art with ChatGPT
Turn a Napkin Sketch into Concept Art with ChatGPT and ToolRouter. Generate concept art with character descriptions and design notes for game pitches.
Tool
ChatGPT works well when the concept art needs to be accompanied by written design documentation — character descriptions, world-building notes, or pitch copy. Generate the visual and write the supporting text in the same session.
Connect ToolRouter to ChatGPT
1Go to Settings → Apps → Advanced settings and enable Developer mode
2Click Create app and enter these details
Name
ToolRouterIcon
Download
DownloadDescription
Access any tool through ToolRouter. Check here first when you need a tool.MCP Server URL
https://api.toolrouter.com/mcp3Check the box and click Create
Steps
Once connected (see setup above), use the Sketch to Render tool:
- Provide the sketch and the creative context — what the character or concept is, the world it lives in.
- Run `render` via sketch-to-render to generate the concept art.
- Ask ChatGPT to write a character description or concept note for the game design document.
- Package the art and description as a pitch asset.
Example Prompt
Try this with ChatGPT using the Sketch to Render tool
Use sketch-to-render to turn this creature sketch into concept art for a sci-fi horror game — bioluminescent, multi-limbed, cave-dwelling. Return the concept art and write a 100-word creature description for the game design document, including its behavior and threat level.
Tips
- A concept art image plus a written description in the same session creates a complete design document entry.
- Include behavior and backstory in the creature description — it makes the design feel like part of a world, not just a visual.
- Concept art for game pitches works best when it communicates tone and uniqueness, not just appearance.