Under the hoodTier: how much it should matter to you
4Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
SDKArea: what it touches
Internal ChangesKind: in v2.1.300,
What probably matters to youSection of the release
What
The SDK lets other programs send messages into Claude Code. Its user message format gains a field, text_not_typed, marked as internal. It says no person typed the message's text: a server or app composed it.
Such text is delivered as written:
no slash-command handling
no expansion of @ mentions beyond the message's own files
no reminders triggered by keywords
Unlike client_composed, the pass that adds context at the start of a turn still runs. The field's own description says the checks of whether a message's words are the user's own do not read this mark yet.
Why
This lays groundwork for treating app- or server-composed messages as untyped, and by its own description it is only partly wired up so far.
