checkpoint

Checkpoint — return in thirty seconds

A session ends; the work doesn't. Whoever returns — the user after a week, or a fresh session after a context reset — faces scrollback that no longer exists and a directory that doesn't explain itself. Reconstruction eats the first twenty minutes and gets details wrong. This skill keeps one file that makes return instant, and a second file that carries orders across the gap without letting them go stale.

CHECKPOINT.md — the return point

Update memory/CHECKPOINT.md whenever a large unit of work completes or the session is winding down. Five sections, always in this order:

# Checkpoint — <goal> — <YYYY-MM-DD HH:MM>

## The story so far
<Thirty seconds of reading, no more. What this work is and where it
stands, told to someone with zero context.>

## Decided
<Decisions confirmed since the last checkpoint — one line each, with
ledger ids where they exist.>

## Waiting on the user
<Decisions only the user can make, and the readings in force from
OPEN-QUESTIONS that are due a question — one line each, so they get asked
here, at the break, not mid-flow. Empty is a valid and welcome state.>

## Next first action
<ONE line, executable immediately without reading anything else.>

## Tried
<Approaches attempted that did not work, one line each with why.>

Rules:

• Next first action is the load-bearing line. A cold session must be able to execute it before reading a single other file: concrete verb, concrete object, no prerequisite. "Continue the analysis" fails this test; "run the export script against the staging list and diff the counts" passes.
• Tried is a map of dead ends. An approach that failed and went unrecorded will be attempted again, in good faith, by a session that has no way to know better. One line per dead end — what was tried, why it didn't work.
• Archive on every update. Before overwriting, copy the outgoing version to memory/checkpoints/{YYYYMMDD-HHMM}-<short-title>.md. That directory is append-only and sorts itself by filename — the full trail of how the work moved, at zero extra cost.
• Index each file the first time it appears. When this skill first creates memory/CHECKPOINT.md, memory/checkpoints/, or memory/HANDOFF.md, add a row for it to the File map in memory/00-INDEX.md — a file missing from the map is a file the next session never opens.