> ## Documentation Index
> Fetch the complete documentation index at: https://ampersand-24eb5c1a-feat-always-enabled-object.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Upsert custom fields for connection

> Create or update fields in the SaaS instance tied to a connection. Only HubSpot and Salesforce are supported currently.