Pressing \\[notmuch-search-show-thread] on any line displays that thread. The '\\[notmuch-search-add-tag]' and '\\[notmuch-search-remove-tag]'
keys can be used to add or remove tags from a thread. The '\\[notmuch-search-archive-thread]' key
is a convenience for archiving a thread (removing the \"inbox\"
-tag). The '\\[notmuch-search-tag-all]' key can be used to add or remove a tag from all
-threads in the current buffer.
+tag). The '\\[notmuch-search-tag-all]' key can be used to add and/or remove tags from all
+messages (as opposed to threads) that match the current query. Use with caution, as this
+will also tag matching messages that arrived *after* constructing the buffer.
Other useful commands are '\\[notmuch-search-filter]' for filtering the current search
based on an additional query string, '\\[notmuch-search-filter-by-tag]' for filtering to include