# Memento Skill

> Controlled recall for research memory, experiment tracking, evidence ledgers, hypothesis updates, archival recall, and next high-information experimental contrasts.

- Skill: `waterdrop26651/memento-skill` (Agent Skill, multi-file: 5 files)
- Install (CLI): `npx skillmds@latest add waterdrop26651/memento-skill`
- Raw SKILL.md: https://api.skillmd.com/api/skills/waterdrop26651/memento-skill/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Research & Search
- License: MIT
- Author: waterdrop26651 (https://skillmd.com/u/waterdrop26651)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/waterdrop26651/memento-skill

---


# Memento Skill

## Overview

Memento Skill treats research memory as a controlled recall problem. External
records help an agent continue work across sessions, but they can also pollute
the next decision if stale notes, weak evidence, or misleading summaries are
read as current facts.

The goal is not to remember everything. The goal is to keep the current decision
surface clear: facts in one ledger, contrasts in another, beliefs in a third,
and stale fragments behind an archive index until there is a real reason to
recall them.

Default stance: optimize for fast continuation, not exhaustive replay. A good
tracker lets a fresh agent recover the current decision surface quickly without
re-reading the whole experimental past.

## Use this skill when

- The user wants an experiment tracker, ablation plan, run table, or research log.
- The project has many runs and needs a global landscape rather than ad hoc notes.
- The user wants help picking the next experiment by information gain, not intuition alone.
- The user wants to compare predictions against outcomes and update beliefs systematically.
- The user wants to prevent old context, archived findings, or memory fragments
  from becoming accidental instructions.

## Core rules

- Maintain both views at once: the global landscape and the next local gradient.
- Separate active decision support from archival completeness.
- Add a contrast before launching a run.
- Change one primary axis per contrast; keep the rest controlled enough to interpret.
- Prefer experiments whose outcome would most change the roadmap.
- Negative results are useful if the prediction was explicit and the control was clean.
- The worst result is a bad contrast that teaches nothing.
- If an old experiment no longer changes the next decision, demote it out of the
  default working set.
- Do not let every note become a tattoo: a fragment must be classified,
  checked, and placed in the right memory layer before it drives action.

## Required working set

- `runs.csv`: factual ledger, one row per run.
- `contrasts.csv`: reasoning ledger, one row per controlled comparison.
- `hypotheses.md`: belief ledger, one section per claim and update rule.

If these files do not exist, create them. Use the starter schemas in [references/TEMPLATES.md](references/TEMPLATES.md).

## Preferred layered layout

For medium or large research programs, prefer this layout:

- `CURRENT_STATE.md`: the minimum entry point for a fresh agent. Keep it short.
- `ACTIVE_TRACKER.md` or `ACTIVE_TRACKER.csv`: only experiments that still have
  decision gradient for the current roadmap.
- `EVIDENCE_LOG.md`: compressed statement of what the project currently believes
  and which few experiments justify that belief.
- `runs.csv`, `contrasts.csv`, `hypotheses.md`: the full ledger.
- `archive/`: experiments and tracker snapshots that should not be read by
  default.
- optional `ARCHIVE_INDEX.md`: a searchable index for cold-memory recall.
- optional archive cards: one short note per archived cluster explaining when it
  should ever be revisited.
- optional `RECALL_NOTES/`: small audit trail for archive recalls that actually
  happened.

Think of these as memory layers:

- hot path: `CURRENT_STATE.md`, `ACTIVE_TRACKER.*`, `EVIDENCE_LOG.md`
- full ledger: `runs.csv`, `contrasts.csv`, `hypotheses.md`
- cold memory: `archive/`, `ARCHIVE_INDEX.md`, archive cards, `RECALL_NOTES/`

Compatibility rule:

- Do not break projects that only have `runs.csv`, `contrasts.csv`,
  `hypotheses.md`.
- When the tracker has become too large, introduce the layered files above and
  make them the default reading path.
- Do not require archive files for projects that do not need cold-memory recall
  yet.

## Archive recall model

Treat archive as a cold-memory layer, not as dead storage and not as part of the
default read path.

Rules:

- Do not read archive by default.
- Only recall archive when the current problem justifies it.
- Recall should begin from an index or archive card, not from blind directory
  traversal.
- Recall is for extracting reusable assets, not for replaying the entire old
  branch.
- If recall finds a still-useful result, promote that result back into the hot
  path (`CURRENT_STATE.md`, `ACTIVE_TRACKER.*`, `EVIDENCE_LOG.md`) rather than
  leaving it buried.

Recommended recall triggers:

- current mainline has stalled or failed repeatedly
- current question is structurally similar to an archived question
- a new result conflicts with the active project story
- a high-value anomaly appears and active evidence does not explain it
- the user explicitly asks for historical excavation

Recommended recall budget:

- first read `ARCHIVE_INDEX.md` or the relevant archive card
- select at most 1-2 archive clusters
- read at most 1-3 source files per cluster before deciding whether to stop
- write a short recall note if the recall materially informs the next step

## Workflow

1. Read the smallest authoritative entry point first: prefer `CURRENT_STATE.md`,
   then `ACTIVE_TRACKER.*`, then `EVIDENCE_LOG.md`, then the full ledger only as
   needed.
2. Identify the active questions, hypotheses, and unresolved decision points.
3. Mark old experiments as one of:
   - `active`: still changes current decisions
   - `reference`: useful supporting evidence but not part of the default working set
   - `archived`: historical only unless a specific question reopens
4. Propose candidate contrasts and rank them by expected information gain.
5. Write the prediction before execution: direction, minimum meaningful delta,
   and reason.
6. Record observed facts in `runs.csv`, not interpretation.
7. Update `contrasts.csv` with actual deltas, information gain, and next
   action.
8. Update `hypotheses.md` based on the gap between expected and observed
   results.
9. If archive recall is triggered, consult `ARCHIVE_INDEX.md` or archive cards,
   do a bounded read, and summarize reusable findings in a recall note.
10. Promote any recalled high-value finding into the hot path instead of keeping
    it archive-only.
11. Refresh `CURRENT_STATE.md` and `ACTIVE_TRACKER.*` so a new agent can resume
    without replaying the whole ledger.
12. If tracker files exist, run
    `python <path-to-this-skill>/scripts/validate_tracker.py <tracker_dir>`
    after editing them. Resolve the script path relative to this `SKILL.md`.

## Deliverables

When using this skill, produce:
- A concise landscape summary
- The most informative next contrasts, ranked
- The control requirements for each contrast
- The predicted gradient or decision impact for each contrast
- Explicit hypothesis updates after new evidence
- A statement of what moved into the active set, what stayed as reference, and
  what was archived out of the default reading path
- When archive recall happened: why recall was triggered, what was read, what
  reusable asset was found, and whether it changed the plan

## Quality bar

- `runs.csv` should store facts and quality flags, not conclusions.
- `contrasts.csv` should make it obvious what changed, what stayed controlled, what was predicted, and what was learned.
- `hypotheses.md` should state what would change the belief, not just the belief itself.
- If a contrast is weakly controlled, mark it inconclusive instead of pretending it resolved the question.
- `CURRENT_STATE.md` should be readable in one short sitting.
- `ACTIVE_TRACKER.*` should contain only the experiments with nontrivial current
  decision gradient.
- Historical completeness belongs in the ledger and archive, not in the default
  agent entry point.
- Archive should be indexed by problem value, not only by date or snapshot name.
- Useful archived findings should be promotable back into the hot path with
  minimal rewriting.

See [references/REFERENCE.md](references/REFERENCE.md) for the full rubric and [references/TEMPLATES.md](references/TEMPLATES.md) for starter files and examples.

