> ## Documentation Index
> Fetch the complete documentation index at: https://www.plain.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# upsertTenantField

> Sets or updates a field value for a specific tenant. Identify the target field using `tenantFieldIdentifier` (tenant ID + external field ID) and pass exactly one value argument matching the schema's `type` (e.g. `stringValue`, `numberValue`, `booleanValue`, `arrayValue`, `dateValue`, or `userReferenceValues`). Requires `tenant:edit` permission.