Update Revit custom properties by web API

It is possible to update and save a custom text attribute in a Revit project hosted on BIM360 ? Our customer's advisor say it is possible, but after taking a look to the Forge API I do not see any reliable way to do it. I'm wrong or I've missed something ?

Solution

I guess they are referring out new API, Design Automation for Revit V3, the new V3 API is still in Beta, but it has the ability to do the following task related to Revit file, including modify your Revit model:

Create custom Revit family content
Automate model creation
Explore and analyze model data
Extract and produce automated reports
Modify existing models to maintain company standards
Automatically create documentation

Also please check Learn Forge about Modify Model as the sample on detail steps of implementation.