brain:rescan · diff
git:20260426.d53cc6c to git:20260914.e75f220
1 added, 1 removed. Audit A to A.
---
name: brain:rescan
- description: "Incremental rescan of project folder. Detects new/changed files since last scan, extracts knowledge from CLAUDE.local.md, memory files, and doc inventory, and updates the brain DB. Requires an existing project_brain.db — run /brain-init first if none exists."
+ description: "Use when project files changed since the last brain scan, CLAUDE.local.md was updated, or a periodic refresh is due. Rescans incrementally, writes new entities, decisions, and documents; needs project_brain.db (run /brain-init first)."
---
# /brain:rescan --- Incremental Knowledge Rescan
Detects what changed since the last scan and updates the brain DB with new knowledge.
## Prerequisites
- `project_brain.db` must exist in the project folder (or parent). If not found, tell the user: "No brain DB found. Run `/brain-init` first."
- At least one project must exist in the DB.
## Procedure
### Step 1: Run the scanner
```bash
python3 ~/.claude/skills/brain/scripts/brain/brain_cli.py scan
```
Check the output:
- If `is_first_scan: true` → this folder was never scanned. Tell the user and proceed with full scan.
- If `new_files: 0` and `changed_files: 0` → "Everything up to date. No changes since last scan ({last_scan})." → done.
- Otherwise, show the delta:
```
RESCAN DELTA
============
Last scan: {last_scan}
New files: N
Changed files: N
Removed files: N
Unchanged: N
New/changed files:
+ docs/NewDoc.html (new)
~ CLAUDE.local.md (changed)
+ emails/Latest_Thread.txt (new)
Knowledge sources:
CLAUDE.local.md: found / not found (changed: yes/no)
Memory files: N files (N new/changed)
Documents: N new, N changed
Emails: N new, N changed
```
### Step 2: Process only new/changed files
Follow the same extraction logic as `/brain-init` Step 4, but **only for files in the delta**:
#### If CLAUDE.local.md is new or changed:
- Re-read and extract entities, decisions, events
- Use `upsert_entity` so existing entities get updated rather than duplicated
- For decisions: check existing decisions in DB, only add genuinely new ones (compare decision text)
#### If memory files are new or changed:
- Read only the new/changed memory files
- Extract project decisions, system references
#### For new/changed documents and emails:
- Register as `document` entities via `upsert_entity`
- Metadata includes path, type, size
#### For removed files:
- Do NOT auto-delete entities. Just report: "N files removed since last scan. Their brain entities are preserved — delete manually if needed."
### Step 3: Present extraction summary
```
RESCAN RESULTS
==============
Project: {name} ({slug})
New/updated entities: N (list)
New decisions: N (list)
New events: N (list)
New document entities: N (list)
Skipped (unchanged): N files
Total proposed writes: NN
```
Ask: **"Write to brain? [Y/n/adjust]"**
### Step 4: Execute writes and update manifest
Same write order as `/brain-init` Step 6:
1. Entities (upsert)
2. Relationships
3. Decisions (dedup check)
4. Events (dedup check)
5. Document entities (upsert)
After all writes, sync to MemPalace and brain.json:
```python
from brain.memory_bridge import full_sync
full_sync("project_brain.db", project_slug)
```
Then update the manifest:
```bash
python3 ~/.claude/skills/brain/scripts/brain/brain_cli.py scan-update
```
### Step 5: Report
```
BRAIN UPDATED (rescan)
======================
Entities: +N, ~N updated (total: N)
Decisions: +N (total: N)
Events: +N (total: N)
Documents: +N (total: N)
Manifest updated: N files tracked
Next scan will only process changes after {now}.
```
## When to use /brain-rescan vs /brain-update
| Scenario | Use |
|----------|-----|
| End of conversation session | `/brain-update` (extracts from conversation) |
| New files added to project folder | `/brain-rescan` (extracts from files) |
| Updated CLAUDE.local.md | `/brain-rescan` |
| First time in a project with existing brain | `/brain-init` (handles both init + scan) |
| Periodic refresh | `/brain-rescan` |