# CONFIG_INVALID

The configuration, or a definition it loads, declares something Nextly cannot use.

## Cause

The configuration, or a definition it loads, declares something Nextly cannot use.

Before it acts, the command checks each declaration in the configuration, and in the definitions it loads: plugins, the Schema Builder's file, blocks. A field's `type` must be a built-in type or one an installed plugin offers, and each option must be one its type accepts. The Why line names each declaration at fault by its path in the configuration.

## Fix

Fix each declaration the Why line lists. For a field type a plugin offers, install the plugin and add it to `plugins` in `nextly.config.ts`. Then run the command again.

## Example

```text
✗ The configuration declares a field Nextly cannot use.
  Why:  collections.posts.rating.type: Invalid field type 'stars'. No built-in type, and no installed plugin offers it on this surface.
  Next: Fix each declaration listed in `nextly.config.ts`, or install the plugin that offers its field type, then run the command again.
  Docs: https://nextlyhq.com/docs/cli/errors/config-invalid  (CONFIG_INVALID)
```