Fields & Types

Field Types

ACMS supports the following field types:

Type	Description	Editor
string	Short text	Single-line input
text	Long text	Multi-line textarea
number	Numeric values	Number input
boolean	True/false	Toggle switch
array	Lists of items	List editor with add/remove/reorder
object	Nested groups	Grouped fields
image	Image URLs	Image input (with preview)

Field types are stored in the _meta section of acms.json and can be changed via the dashboard or API.

Auto-Detection and Type Inference

ACMS infers field types from usage context:

• Accessing a field in an <img src> attribute suggests an image type
• Numeric comparisons suggest a number type
• Boolean conditionals suggest a boolean type
• Array methods (.map, .forEach) suggest an array type

The inferred type is stored in metadata and determines which editor is shown in the dashboard.

Field Metadata

Every field has an entry in _meta that tracks:

{
  "_meta": {
    "hero.title": {
      "type": "string",
      "lastAccessed": "2025-01-15T10:30:00.000Z"
    }
  }
}

• type — The field type (determines the editor in the dashboard)
• lastAccessed — Timestamp of the last time this field was accessed in code (used by purge to remove unused fields)
• label — Optional human-readable label
• defaultValue — Optional default value
• itemType — For array fields, the type of each item

Changing Field Types

You can change a field’s type in three ways:

1. Dashboard — Click the type badge next to any field to change it
2. API — PATCH /api/field/:path/meta with a new type value
3. Manually — Edit the _meta section of acms.json

Next Steps

• Understand Content Strategies for build-time vs runtime delivery
• Set up TypeScript for full type safety