What probably matters to youSection of the release
What
Marketplaces can now offer a plugin as a downloadable zip. A new source kind archive takes an HTTPS zip URL plus an optional sha256 pin; when the pin is set every download is checked against it and the install is refused on mismatch, and the digest also stands in as the plugin's version when none is declared.
Details
Downloads are hardened against server-side request forgery: HTTPS only, loopback, link-local and cloud-metadata hosts refused, at most 5 redirects, a 256 MB size cap, a 120 second timeout, and a fixed User-Agent of Claude-Code-Plugin-Manager.
Headers configured on the enclosing marketplace url-source are only reused when the origin matches.
Installed plugin records gained a contentSha256 field, and the temp directory used during install has an "archive" naming case.
Evidence
plugin archive URL policy rejected
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
