diff --git a/understand-anything-plugin/skills/understand/SKILL.md b/understand-anything-plugin/skills/understand/SKILL.md
index b66dcc2..610a9dd 100644
--- a/understand-anything-plugin/skills/understand/SKILL.md
+++ b/understand-anything-plugin/skills/understand/SKILL.md
@@ -770,9 +770,16 @@ Report to the user: `[Phase 7/7] Saving knowledge graph...`
    }
    ```
 
-4. Clean up intermediate files:
+4. Clean up intermediate files, **preserving `scan-result.json`** so future incremental runs can skip Phase 1 SCAN (see issue #293):
    ```bash
-   rm -rf $PROJECT_ROOT/.understand-anything/intermediate
+   # Preserve scan-result.json — Phase 1's deterministic file inventory.
+   # Future incremental runs (Phase 2 compute-batches.mjs --changed-files=…)
+   # need this inventory; without it, Phase 1 must re-dispatch and pay ~157k
+   # tokens / ~158s per incremental run.
+   INTER="$PROJECT_ROOT/.understand-anything/intermediate"
+   if [ -d "$INTER" ]; then
+     find "$INTER" -mindepth 1 -maxdepth 1 -not -name 'scan-result.json' -exec rm -rf {} +
+   fi
    rm -rf $PROJECT_ROOT/.understand-anything/tmp
    ```