I have a quirky one when trying to add to sharepoint navigation:
_api/Web/Navigation/GetNodeById(2031)/Children
It only works with the following which ends up meaning i need to go back in and delete junk out of the URL if you put the full url i.e. https:// flow does some funky stuff and trys to be too smart ! 😞
{
"__metadata": { type: "SP.NavigationNode" },
'IsExternal': false,
'Title': "@{triggerBody()?['Title']}",
'Url': "//tenant.sharepoint.com/sites/Customers/Lists/Customers/DispForm.aspx?ID=@{triggerBody()?['ID']}"
}