Update Today

AGENTS.md

@@ -33,3 +33,23 @@ make -j$(nproc)
 systemctl restart bytetrack-counter
 journalctl -u bytetrack-counter -f
 ```
+
+## Reset via .reset file
+
+Place a `.reset` file in `SHM_DIR` (default `/dev/shm/bytetrack-counter`) to trigger a full state reset:
+
+- **Startup**: deleting `.reset` before service starts clears all state files on boot
+- **Runtime**: dropping `.reset` while service runs calls `BatchStore::reset()` — ends active batch, clears in-memory state, deletes `STATE_FILE`, clears live stream JPEG + writes blank frame on next write
+
+```bash
+touch /dev/shm/bytetrack-counter/.reset
+```
+
+## Shared memory
+
+`SHM_DIR` (`/dev/shm/bytetrack-counter` by default) stores:
+- `LIVE_STREAM_FRAME_PATH` JPEG snapshot
+- `RECORD_SHM_DIR` video recordings before move to disk
+- `.reset` trigger file
+
+Directory auto-created at startup.