Orion/.agents/skills/orion-fold/SKILL.md

name	description
orion-fold	Roll up the oldest 2^k entries of an Orion vault's wiki/log.md into a fold page in wiki/folds/, moving the entries verbatim and leaving one pointer line, so the log stays cheap to read. Dry-run by default; writes only on --commit. Run when cascade reports more than 16 unfolded entries. Triggers on: fold the log, run a fold, log rollup, roll up the log.

orion-fold — subtractive log rollup

The log is append-only, so it grows forever. A fold moves the oldest entries into a fold page — verbatim, lossless — and leaves one pointer line behind. Entries are never edited or deleted; they live one file over.

When: orion-cascade prints Log: N / 16 every run. Over 16 → a fold is due. Default k=4 (16 entries).

Parameters

• k (default 4) — batch size 2^k.
• --commit — write. Without it, dry-run: print the fold, write nothing.

Fewer than 2^k unfolded entries → report the shortfall and stop.

Entry format

An entry is everything from one ^## YYYY-MM-DD heading to the next. The log is newest-first, so the oldest entries are at the bottom. A heading containing [folded] is a pointer, not an entry.

Fold ID

fold-k{K}-from-{EARLIEST}-to-{LATEST}-n{COUNT} — e.g. fold-k4-from-2026-01-02-to-2026-01-30-n16. If wiki/folds/<ID>.md exists, stop.

Procedure

1. Select the oldest 2^k unfolded entries — from the bottom up.

2. Self-check (blocking):

   • No unfolded entry sits below your span. If one does, you've picked a middle window — a hole later folds will never revisit. Re-pick.
   • Every selected entry was located exactly (date + title). Never remove an entry you didn't positively match — leave it and report.
   • Every numeric claim you'll write is present in a child entry.

3. Write the fold page (wiki/folds/<ID>.md):

   ---
   type: fold
   fold_id: <ID>
   entry_count: N
   entry_range: {from: YYYY-MM-DD, to: YYYY-MM-DD}
   created: YYYY-MM-DD
   tags: [meta, fold]
   ---
   

   Sections:

   1. Scope — one paragraph: period and dominant themes.
   2. Entries — table Date | Title | One-sentence summary.
   3. Key outcomes — 3–7 bullets, each citing its entry's date.
   4. Cross-entry themes — 0–4 bullets, each naming ≥2 entries, or "None".
   5. Contradictions or corrections — or "None detected".
   6. Entries — verbatim — the moved entries in full, headings demoted ## → ###, otherwise untouched.

   Extractive only. Nothing that isn't in the entries.

4. Dry-run: print the page and what commit would do. Stop.

5. On --commit:

   1. Write the fold page.
   2. Remove the folded entries from log.md; where the newest of them sat, leave: ## {TO} — [folded] {N} entries ({FROM} to {TO}) → [[wiki/folds/{ID}|{ID}]]
   3. Add the fold to ## Folds in wiki/index.md.
   4. Prepend a log entry: ## {TODAY} — [vault] Log fold: {N} entries ({FROM} to {TO}), with log line count before → after.

6. Reconcile: entries remaining in log.md + entries in all fold pages = entries before. If it doesn't balance, stop and report.

Rules

• Dry-run by default. Write only on --commit.
• Subtractive and lossless — entries move verbatim; never edited, never deleted.
• Oldest first, verified. No unfolded entry below the span.
• Never remove what you didn't positively match.
• Extractive only.
• Reconcile before finishing.