diff --git a/tests/rag_evaluation/README.md b/tests/rag_evaluation/README.md
index 1409a5e..3f571b2 100644
--- a/tests/rag_evaluation/README.md
+++ b/tests/rag_evaluation/README.md
@@ -116,6 +116,7 @@ uv run python tools/rag_eval_cli.py upload \
 **Optional flags:**
 - `--category CATEGORY` - Custom category for notes (default: `nfcorpus_rag_eval`)
 - `--force-download` - Re-download nfcorpus dataset
+- `--force` - Delete all existing notes in the target category before uploading (efficient corpus refresh)
 
 **Important:** This step requires:
 - A running Nextcloud instance with vector sync enabled
diff --git a/tools/rag_eval_cli.py b/tools/rag_eval_cli.py
index d3d8d74..30f14c9 100644
--- a/tools/rag_eval_cli.py
+++ b/tools/rag_eval_cli.py
@@ -411,19 +411,26 @@ def generate(provider: str, model: str | None, force_download: bool):
     is_flag=True,
     help="Force re-download of nfcorpus dataset",
 )
+@click.option(
+    "--force",
+    is_flag=True,
+    help="Delete all existing notes in the target category before uploading",
+)
 def upload(
     nextcloud_url: str,
     username: str,
     password: str,
     category: str,
     force_download: bool,
+    force: bool,
 ):
     """Upload nfcorpus corpus documents as Nextcloud notes.
 
     This command:
     1. Downloads nfcorpus dataset (if not already cached)
-    2. Uploads all corpus documents as Nextcloud notes
-    3. Saves document ID → note ID mapping to fixtures/note_mapping.json
+    2. Optionally deletes existing notes in target category (--force)
+    3. Uploads all corpus documents as Nextcloud notes
+    4. Saves document ID → note ID mapping to fixtures/note_mapping.json
 
     The note mapping file is used by pytest tests to map expected document IDs
     to actual note IDs in Nextcloud.
@@ -451,48 +458,89 @@ def upload(
         )
 
         try:
-            # Upload documents
-            click.echo(f"\nUploading {len(corpus)} documents as notes...")
+            # Delete existing notes in category if force is specified
+            if force:
+                click.echo(
+                    f"\n--force specified: Deleting existing notes in category '{category}'..."
+                )
+                deleted_count = 0
+                async for note in nc_client.notes.get_all_notes():
+                    if note.get("category") == category:
+                        try:
+                            await nc_client.notes.delete_note(note["id"])
+                            deleted_count += 1
+                            if deleted_count % 100 == 0:
+                                click.echo(f"  Deleted {deleted_count} notes...")
+                        except Exception as e:
+                            click.echo(
+                                f"  Error deleting note {note['id']}: {e}", err=True
+                            )
+
+                click.echo(
+                    f"Deleted {deleted_count} existing notes in category '{category}'"
+                )
+
+            # Upload documents concurrently
+            click.echo(f"\nUploading {len(corpus)} documents as notes (concurrent)...")
             click.echo(f"Category: {category}")
 
             note_mapping = {}
             uploaded_count = 0
+            upload_errors = []
 
-            for doc_id, doc in corpus.items():
-                # Create note via Notes API
-                # Title includes doc ID for easy mapping
-                title = f"[{doc_id}] {doc['title'][:100]}"  # Truncate long titles
-                content = doc["text"]
+            # Semaphore to limit concurrent uploads (avoid overwhelming server)
+            max_concurrent = 20
+            semaphore = anyio.Semaphore(max_concurrent)
 
-                try:
-                    note_data = await nc_client.notes.create_note(
-                        title=title,
-                        content=content,
-                        category=category,
-                    )
+            async def upload_document(doc_id: str, doc: dict[str, Any]):
+                """Upload a single document as a note."""
+                nonlocal uploaded_count
 
-                    # Store mapping
-                    note_id = note_data["id"]
-                    note_mapping[doc_id] = note_id
+                async with semaphore:
+                    title = f"[{doc_id}] {doc['title'][:100]}"  # Truncate long titles
+                    content = doc["text"]
 
-                    uploaded_count += 1
-
-                    # Progress indicator every 100 docs
-                    if uploaded_count % 100 == 0:
-                        click.echo(
-                            f"  Uploaded {uploaded_count}/{len(corpus)} documents..."
+                    try:
+                        note_data = await nc_client.notes.create_note(
+                            title=title,
+                            content=content,
+                            category=category,
                         )
 
-                except Exception as e:
-                    click.echo(f"  Error uploading {doc_id}: {e}", err=True)
+                        # Store mapping
+                        note_id = note_data["id"]
+                        note_mapping[doc_id] = note_id
+
+                        uploaded_count += 1
+
+                        # Progress indicator every 100 docs
+                        if uploaded_count % 100 == 0:
+                            click.echo(
+                                f"  Uploaded {uploaded_count}/{len(corpus)} documents..."
+                            )
+
+                    except Exception as e:
+                        error_msg = f"Error uploading {doc_id}: {e}"
+                        upload_errors.append(error_msg)
+                        click.echo(f"  {error_msg}", err=True)
+
+            # Upload all documents concurrently using task group
+            async with anyio.create_task_group() as tg:
+                for doc_id, doc in corpus.items():
+                    tg.start_soon(upload_document, doc_id, doc)
 
             click.echo(f"\nUploaded {uploaded_count} documents successfully")
+            if upload_errors:
+                click.echo(
+                    f"Encountered {len(upload_errors)} errors during upload", err=True
+                )
 
             # Save note mapping
             with open(NOTE_MAPPING_FILE, "w") as f:
                 json.dump(note_mapping, f, indent=2)
 
             click.echo(f"Saved note mapping to: {NOTE_MAPPING_FILE}")
+            click.echo(f"  Mapped {len(note_mapping)} document IDs to note IDs")
 
         finally:
             # Close the Nextcloud client