Field explanations
- Top-level settings define the tool behavior
- Environment-specific blocks override defaults
- Paths are usually relative to the config file or project root
- Secrets should be referenced, not committed
Minimal template
{
"name": "example",
"enabled": true
}Common usage patterns
- Keep vercel.json small and reviewable
- Use comments only when the format supports them
- Commit example files with placeholder values
- Validate locally before deploying
Common errors
- SPA 404 after refresh
- Wrong output directory
- Headers not applied
- Build command mismatch
Online validation
Validate syntax first, then compare behavior against your deploy target. For JSON-based configs, use the JSON formatter before debugging tool-specific behavior.