memory-distill

Note: /mempenny:memory-distill operates on a single file via its explicit path argument, so it does not need --dir. The file path IS the target.

Distill a single memory file in-place. No backup — this operation is small and the user can recover from the filesystem's own history if they care.

Step 1 — Parse arguments

The user invoked this command with: $ARGUMENTS

• First positional argument — absolute path to a memory file. Required.
• --lang <code> — output language for the distilled replacement and UI labels. If not passed, check MEMPENNY_LOCALE env var. Default en.

Step 2 — Load locale strings

2a — Validate <lang> before reading (H2: path traversal guard)

Before constructing the locale path, validate that <lang> matches the regex ^[a-zA-Z]{2,3}(-[A-Za-z0-9]{2,8})?$. If it does not match, treat it exactly like a missing locale: silently reset <lang> to en and warn with errors.locale_missing.

Read ${CLAUDE_PLUGIN_ROOT}/locales/<lang>/strings.json. Fall back to en and warn with errors.locale_missing if missing. You need distill.* labels and distill_output_instruction.

Step 3 — Validate the input file path

Before touching the file, apply the following validation. On any failure, print errors.memory_dir_not_found and STOP — do not read the file.

1. Regex (C1): the raw argument must match ^/[A-Za-z0-9/_.\ -]{1,4096}$. Reject anything that doesn't match.
2. Symlink check (pre-realpath): [ ! -L "<path>" ] — reject if the path is a symlink. This check runs BEFORE realpath because realpath follows symlinks.
3. Realpath: run realpath "<path>" via Bash. Use the resolved value for all subsequent steps. (held as $resolved for the rest of the flow)
4. Regex re-check: the resolved path must also match ^/[A-Za-z0-9/_.\ -]{1,4096}$. Reject if it does not.
5. Confinement: the resolved path's parent directory must equal {MEMORY_DIR} (the file must be directly inside the memory dir — not a descendant of a subdirectory, and not escaping via symlink). Always auto-detect {MEMORY_DIR} from the current project mapping (this command does not accept --dir). Use the same H5 4-check pattern as clean.md Step 3 to validate the auto-detected path (regex → realpath → depth → existence + not-a-symlink). If auto-detection fails, print errors.memory_dir_not_found and STOP.
6. Existence + regular file: [ -f "<resolved>" ] — reject if absent or not a regular file.