Bags can be created or updated over HTTP by using the HTTP API to access /bags/{bag_name} to send a {{{PUT}}} request containing a JSON bag. The content-type header must be set to application/vnd.tiddlyweb+json¹.

To make edits to a bag that already exists in the store the current user must pass the manage constraint on the bag. To create a new bag, the current user must pass the bag_create_policy.

See How can I use curl to create stuff in TiddlyWeb? for a simple example.