jev-compaction

Compaction and handoffs with Jev

Jev cannot write a summary. What it does is read the transcript turn by turn and mark each one:

• keep: carries a decision, a constraint, a preference, unfinished work, or an exact value, path, id, command or error that later work depends on. Survives word for word.
• summarize: background whose gist matters.
• drop: chatter, superseded attempts, repeated output.

You then summarize a fraction of the transcript, with the lines that must not be paraphrased already flagged. Handoffs get shorter and stop losing the one line that mattered.

Do this

1. Get the transcript as a list of {role, content} messages. On Hermes: hermes sessions export --format jsonl -.

2. Select:

   • Hermes: call jev_compact_select with messages.
   • Anywhere else:

 ```bash
 jev compact-select --digest < transcript.json      # {"messages":[...]} or a bare list
 ```

3. Write the handoff from digest, not from the raw transcript:

• Every [KEEP VERBATIM] line goes in unchanged, grouped under Decisions, Open work, or Pointers (paths, ids, commands).
• [background] lines become at most one short paragraph of context.
• Add nothing that is not in the digest.

1. Keep the handoff under 400 words. If it will not fit, you are paraphrasing keep-lines; list them instead.

Guarantees

• The last six messages are always kept; system messages are always kept.
• Nothing is dropped unless Jev was confident (0.7+). An unjudged turn is summarized, never dropped.
• Turns that look like they hold a secret are not sent; they default to summarize.
• Jev down: every turn comes back summarize, which is exactly what you would have done without it.

When to compact at all

should_compact is arithmetic, not a model call: compact at 60% of the window, urgently at 85%. Do not ask a model whether the window is full.