forget git:20260904.252b54cA

Immutable. This exact content is served forever at /api/v1/blob/a4c0c70fcfe34514.

---
name: forget
description: Delete a lesson, or down-weight one that is merely wrong; use when asked, after saying it cannot be undone.
disable-model-invocation: false
allowed-tools: ["Bash(node ${CLAUDE_PLUGIN_ROOT}/bin/admin.mjs forget:*)", "mcp__plugin_mubit-memory_mubit__mubit_outcome"]
---

Delete with the bundled script, naming the lesson — the `reference_id` cited in recalled
context, or the id on a line of `/mubit-memory:reflect` or `/mubit-memory:strategies`:

```bash
node ${CLAUDE_PLUGIN_ROOT}/bin/admin.mjs forget --data-dir "${MUBIT_CC_DATA_DIR:-${CLAUDE_PLUGIN_DATA}}" <lesson_id>
```

**`--data-dir "${MUBIT_CC_DATA_DIR:-${CLAUDE_PLUGIN_DATA}}"` is not optional.** A Bash tool
call does not inherit `CLAUDE_PLUGIN_DATA` — it arrives empty — so without the flag the script
has to guess which of several `mubit-memory*` directories the host is using, and either
refuses with `no_run` or acts on a run this session's hooks never touch. The host substitutes
`${CLAUDE_PLUGIN_DATA}` into this file before you read it, and the shell default around it
lets a session that pins `MUBIT_CC_DATA_DIR` keep its pin — the same order every hook resolves
in. Pass the whole expression straight through. Do not turn it into an `ENV=… node …` prefix:
that is no longer a `node` command and will stop for a permission prompt.

Confirm the id and the text with the user before you run it; there is no dry run. The script
deletes one lesson by `POST /v2/control/lessons/delete` and nothing else: it has no way to
delete a whole run, on purpose, because that operation removed every capture, trace and
lesson in the run and was one argument away from a single-lesson delete.

There is also no "mark superseded" operation: nothing flags an entry as replaced. Superseding
is done the way described below — write the corrected lesson, and down-weight the old one so
retrieval stops preferring it.

## Read this before deleting

Deletion is **not undoable**. There is no tombstone to restore from, no recycle bin, and the
entry's accumulated reinforcement history — every outcome that ever credited or blamed it —
goes with it.

A lesson that is merely *wrong* is usually better handled with `mubit_outcome` and a negative
signal:

```
mubit_outcome  reference_id=<the lesson>  outcome=failure  signal=-1
               rationale="<why it was wrong, in one sentence>"
```

The promotion pipeline acts on that. The lesson's confidence drops, it stops surfacing near
the top of recall, and — this is the part deletion cannot do — the *reason* it was wrong is
now part of the record. A deleted lesson teaches the system nothing. A down-weighted one
teaches it something, and the correction survives to shape what gets promoted next.

## When deletion is actually right

- The entry should never have existed: a secret, a customer name, a path from someone else's
  machine that slipped past redaction.
- It is factually about a different project and will keep polluting recall here.
- The user asks for it directly, after being told it cannot be undone.

Everything else — a lesson that is outdated, over-general, or true-but-annoying — is a
`mubit_outcome` with a negative signal, or a fresh, better-worded lesson via
`/mubit-memory:remember` that supersedes it in retrieval. Reach for deletion last, not first.