A Claude Code plugin
Summarize the part you have finished. Keep the part you are working on, word for word. The context stops filling with things that stopped mattering.
/plugin marketplace add unclecode/context-keep /plugin install context-keep@context-keep
/keep29% fullThe old half becomes a few lines. The half you are working on is untouched: every path, number and decision still exact.
Three of my own sessions, already measured. The pane
below shows the turns around each zone and how many messages sit
between them; the message that starts each zone is the real one the
tool quoted. Run /keep, hover a zone to see it on the
curve, then choose one and watch the old half fold away.
Take every content word used after a stop. For each use, find where in the session that word first appeared. If it appeared after the stop, the kept part brought it in itself. If it appeared before, the kept part is leaning on something you are about to replace.
The same messages the Rewind picker lists, straight from the file on your disk.
One number per possible stop: the share of the kept part's vocabulary that it did not borrow.
Each rise is measured against the wiggle of its own curve, so a real break and a sub-topic are told apart.
A number to scroll to, the message quoted, and a note to paste that says what to keep exact.
The curve steps up, holds flat, then falls away. The flat run is the safe zone. Stop anywhere inside it.
It steps up and stays up. The break happened, and nothing since has needed the past. Anything newer is as safe and saves more.
No step is clear, but the sub-topics are real. It grades them and lets you choose, rather than pretending there is a clean answer.
Why semantic similarity is degenerate here, the six variants that failed, and what the psychology of memory says about doorways. With every number you can reproduce.
Claude Code does the summarizing, through Summarize up to here in the Rewind picker. This plugin never writes to a session file, never calls a network, and installs nothing. Every run also leaves an interactive page on your own disk.