DefBuilder

Steam Inventory ItemDef editor for Steam game developers. Import, validate, preview, and export JSON in the browser.

DefBuilder is built for faster Steam Inventory authoring without bouncing between raw JSON, reference material, and repeated trial-and-error. Load existing item definition files, edit common fields in a focused interface, review validation feedback, inspect a live preview, and export updated JSON for your workflow.

Features:

• Import existing ItemDef JSON
• Edit common ItemDef fields and metadata
• Validate common schema and authoring issues
• Preview item presentation while editing
• Export clean JSON directly from the browser

DefBuilder is an unofficial third-party tool for Steam Inventory workflows and is not affiliated with or endorsed by Valve.