What probably matters to youSection of the release
What
Before a prompt is sent, it runs through two tiers of prompt.submit hooks, core ones and managed ones. A hook can drop the prompt, which shows a warning and runs no query, or rewrite it, which replaces the text in your message.
Details
When a rewrite changes the text, @-mentions are recomputed: file, directory, MCP resource, agent and nested memory attachments are discarded and re-resolved with read state cleared.
Bash mode, slash commands and inputs that never query skip the chain, and settle with a fixed reason naming those cases.
A rewrite that cannot find the matching user message logs a warning saying the model will see the prompt as you typed it.
Evidence
the prompt did not go through prompt.submit (a command, bash mode, an input that did not query, or a failed pass)
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
