diff --git a/copienator/commands/correction.py b/copienator/commands/correction.py
index fb03fd6..cc0cad4 100644
--- a/copienator/commands/correction.py
+++ b/copienator/commands/correction.py
@@ -532,6 +532,19 @@ def process_single_task(task_tuple, precomputed_response=None):
 
             json_data = parse_correction_response(full_response_text)
 
+            # Validate the whole group before moving PDFs or applying corrections.
+            returned_ids = [entry["id"] for entry in json_data]
+            unexpected = sorted(set(returned_ids) - set(d_data))
+            missing = sorted(set(d_data) - set(returned_ids))
+            duplicates = sorted({pid for pid in returned_ids if returned_ids.count(pid) > 1})
+            if unexpected or missing or duplicates:
+                raise ValueError(
+                    f"Correction ID mismatch: expected {list(d_data)}, "
+                    f"received {returned_ids}; unexpected IDs: {unexpected}; "
+                    f"missing IDs: {missing}; duplicate IDs: {duplicates}. "
+                    "No corrections from this response were applied."
+                )
+
             # Ensure consistency of answer placements
             for p in json_data:
                 pid = p["id"]
@@ -899,7 +912,10 @@ def run_configured(args: argparse.Namespace) -> ExitCode:
                                             "data": b64_img,
                                         }
                                     },
-                                    {"text": prompting.make_prompt(INPUT_DIR, label)},
+                                    {"text": prompting.make_prompt(
+                                        INPUT_DIR, label,
+                                        expected_ids=[row[0] for row in group_data],
+                                    )},
                                 ],
                             }
                         ],
diff --git a/copienator/commands/cutleft.py b/copienator/commands/cutleft.py
index dc60125..56a0672 100644
--- a/copienator/commands/cutleft.py
+++ b/copienator/commands/cutleft.py
@@ -10,6 +10,7 @@ from pathlib import Path
 from queue import Empty, Queue
 from threading import Thread
 
+import pymupdf
 from pdf2image import convert_from_path
 from PIL import Image, ImageTk
 
@@ -31,6 +32,8 @@ DELIMITER_COLOR = (0, 0, 0)
 OUTPUT_SIZE = (1800, 1000)
 CROP_SHIFT_STEP = 50
 CROP_WIDTH_STEP = 50
+RENDER_DPI = 200
+NARROW_PAGE_RATIO = 0.8
 pdf_cache_lock = threading.Lock()
 
 # The requested spelling is kept as the public switch for this alternate layout.
@@ -52,14 +55,17 @@ def distribute_pages(total_pages: int, max_per_file: int = 5) -> list[int]:
 def stitch_images(image_list: list[Image.Image]) -> Image.Image | None:
     if not image_list:
         return None
-    total_width = sum(image.width for image in image_list)
+    # Downstream label coordinates assume equally spaced page columns. Pad
+    # narrower strips instead of scaling their content or vertical coordinates.
+    column_width = max(image.width for image in image_list)
+    total_width = column_width * len(image_list)
     total_width += (len(image_list) - 1) * DELIMITER_WIDTH
     max_height = max(image.height for image in image_list)
     combined = Image.new("RGB", (total_width, max_height), color="white")
     x_offset = 0
     for index, image in enumerate(image_list):
         combined.paste(image, (x_offset, 0))
-        x_offset += image.width
+        x_offset += column_width
         if index < len(image_list) - 1:
             delimiter = Image.new(
                 "RGB", (DELIMITER_WIDTH, max_height), color=DELIMITER_COLOR
@@ -73,7 +79,7 @@ def stitch_images(image_list: list[Image.Image]) -> Image.Image | None:
 def _get_pdf_pages_cached(pdf_path: Path) -> list[Image.Image]:
     # Label coordinates use the full, displayed MediaBox, including on PDFs
     # previously cropped by crop-margins. Keep this in sync with split-answers.
-    return convert_from_path(pdf_path, use_cropbox=False)
+    return convert_from_path(pdf_path, use_cropbox=False, dpi=RENDER_DPI)
 
 
 def get_pdf_pages(pdf_path: Path) -> list[Image.Image]:
@@ -82,6 +88,29 @@ def get_pdf_pages(pdf_path: Path) -> list[Image.Image]:
         return _get_pdf_pages_cached(pdf_path)
 
 
+def normal_page_width(pdf_path: Path, images: list[Image.Image]) -> float:
+    """Infer the unsplit sheet width, including for legacy PDFs without metadata."""
+    reference = max(image.width for image in images)
+    original = pdf_path.parent.parent / "Copies Originales" / pdf_path.name
+    try:
+        if not original.is_file():
+            return reference
+        with pymupdf.open(original) as document:
+            # Landscape scans contain two normal booklet pages; portrait scans
+            # contain one. MediaBox dimensions match get_pdf_pages above.
+            widths = []
+            for page in document:
+                rect = page.mediabox * page.rotation_matrix
+                width = rect.width / 2 if rect.width > rect.height else rect.width
+                widths.append(width * RENDER_DPI / 72)
+            if widths:
+                reference = max(widths)
+    except (OSError, RuntimeError, ValueError):
+        # A missing/unreadable backup must not prevent reviewing a valid copy.
+        pass
+    return reference
+
+
 def process_single_pdf(
     pdf_path: Path,
     shift_offset: int = 0,
@@ -91,10 +120,20 @@ def process_single_pdf(
     """Convert one PDF into a preview, full-resolution splits and metadata."""
     try:
         cropped_images = []
-        for image in get_pdf_pages(pdf_path):
+        images = get_pdf_pages(pdf_path)
+        if not images:
+            return None
+        reference_width = normal_page_width(pdf_path, images)
+        full_width_pages = []
+        for page_index, image in enumerate(images):
             width, height = image.size
             if max_per_file == 1:
                 left, right = 0, width
+            elif width < NARROW_PAGE_RATIO * reference_width:
+                # Secondary subpages start at their own left edge. Keep the
+                # normal margin width, capped to the available page content.
+                left = min(width - 1, max(0, shift_offset))
+                right = min(width, left + int(reference_width // 3) + max(0, width_offset))
             else:
                 left = max(0, 100 + shift_offset)
                 right = min(
@@ -103,6 +142,8 @@ def process_single_pdf(
                 )
             if right > left:
                 cropped_images.append(image.crop((left, 0, right, height)))
+                if left == 0 and right == width:
+                    full_width_pages.append(page_index + 1)
         if not cropped_images:
             return None
 
@@ -123,6 +164,7 @@ def process_single_pdf(
             "total_pages": len(cropped_images),
             "number_of_files": len(split_images),
             "columns_per_file": distribution,
+            "full_width_pages": full_width_pages,
         }
         return preview, split_images, schema
     except Exception as exc:  # noqa: BLE001 - interactive item failure
diff --git a/copienator/prompting.py b/copienator/prompting.py
index 78e4bea..785bafd 100644
--- a/copienator/prompting.py
+++ b/copienator/prompting.py
@@ -1,6 +1,8 @@
 from pathlib import Path
 import io
+import json
 from . import utils
+from . import read_json
 from . import configuration as settings
 from .gemini_config import thinking_config
 
@@ -103,7 +105,7 @@ sur les autres questions."""
 
 from .utils import get_label_text_content, get_label_sol_content, get_label_persp_content
 
-def make_prompt(input_dir,full_label):
+def make_prompt(input_dir,full_label, *, expected_ids=None):
     text = get_label_text_content(input_dir, full_label) or ""
     corr = get_label_sol_content(input_dir, full_label) or ""
     persp = get_label_persp_content(input_dir, full_label) or ""
@@ -117,7 +119,18 @@ def make_prompt(input_dir,full_label):
             + persp
             + "\n```\n"
         )
-    return main_prompt.replace("<<text>>", text).replace("<<corr>>", corr).replace("<<persp>>", persp).replace("<<label>>", full_label)
+    prompt = main_prompt.replace("<<text>>", text).replace("<<corr>>", corr).replace("<<persp>>", persp).replace("<<label>>", full_label)
+    if expected_ids is not None:
+        prompt += (
+            "\n\nIdentifiants exacts présents dans cette image, de haut en bas : "
+            + json.dumps(list(expected_ids), ensure_ascii=False)
+            + ".\nRenvoie exactement un résultat par identifiant de cette liste, "
+            "sans omission, doublon ni identifiant supplémentaire. Conserve les zéros initiaux. "
+            "Utilise uniquement les en-têtes imprimés « ID: … » pour identifier les réponses ; "
+            "ignore les numéros manuscrits. Tout le contenu jusqu’au prochain en-tête "
+            "imprimé appartient au même identifiant, même s’il contient plusieurs feuilles."
+        )
+    return prompt
 
 
 from pydantic import BaseModel, Field, TypeAdapter
@@ -190,8 +203,9 @@ def batch_generation_config(thinking_level):
 # The root model for parsing is be: List[EvaluationEntry]
 def generate_request(input_dir, file, full_label, *, thinking_level=settings.THINKING_LEVEL_PRO):
     """Generates request for Gemini."""
-    prompt = make_prompt(input_dir, full_label)
     image_path = Path(file)
+    group_data = read_json(image_path.with_suffix(".json"))
+    prompt = make_prompt(input_dir, full_label, expected_ids=[row[0] for row in group_data])
 
     contents = [
         types.Content(
diff --git a/copienator_gui/workflow.py b/copienator_gui/workflow.py
index 0c35d7a..e1c213b 100644
--- a/copienator_gui/workflow.py
+++ b/copienator_gui/workflow.py
@@ -289,6 +289,7 @@ def build_workflow(show_personal_steps: bool) -> list[StepDefinition]:
             "Prétraitement des copies",
             "Découper une partie à gauche pour détection des labels",
             "Produit les images de la partie gauche des copies. "
+            "Pour les sous-pages étroites, la marge commence au bord gauche et est limitée à la largeur disponible. "
             "Dans la fenêtre de découpe, utilisez les flèches : ←/→ déplacent la zone "
             "de 50 px vers la gauche/droite, ↑ l’élargit de 50 px et ↓ la réduit de 50 px. "
             "1 utilise les pages entières, Entrée valide et ! signale une erreur."
diff --git a/tests/test_correction_ids.py b/tests/test_correction_ids.py
new file mode 100644
index 0000000..4d669b8
--- /dev/null
+++ b/tests/test_correction_ids.py
@@ -0,0 +1,69 @@
+import json
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import Mock, patch
+
+from copienator import EvaluationWorkspace, atomic_write_json
+from copienator.commands import correction
+
+
+class CorrectionIdTests(unittest.TestCase):
+    def test_mismatched_ids_are_rejected_before_any_side_effects(self):
+        for ids, diagnostic in (
+            (["37", "03", "05"], "unexpected IDs: ['03']"),
+            (["37"], "missing IDs: ['05']"),
+            (["37", "05", "05"], "duplicate IDs: ['05']"),
+        ):
+            with self.subTest(ids=ids), tempfile.TemporaryDirectory() as directory:
+                root = Path(directory)
+                group = root / "Par label" / "Ex 1" / "Group_1.jpg"
+                group.parent.mkdir(parents=True)
+                group.touch()
+                atomic_write_json(group.with_suffix(".json"), [
+                    ["37", 0, 500, 1], ["05", 550, 1000, 1],
+                ])
+                pdf = root / "Copies" / "Copie37" / "Ex 1.pdf"
+                pdf.parent.mkdir(parents=True)
+                pdf.write_bytes(b"original")
+                workspace = EvaluationWorkspace(root)
+                prior = {"Other": [[{"id": "22", "result": {"score": 4}}]]}
+                atomic_write_json(workspace.correction_file, prior)
+                before = workspace.correction_file.read_bytes()
+                args = correction.build_parser().parse_args([str(root)])
+                correction.configure_runtime(workspace, [(str(group), "Ex 1")], args, api_client=Mock())
+                response = [{"id": pid, "result": {
+                    "score": 0, "error": "empty-answer", "feedback": [],
+                }} for pid in ids]
+                with patch.object(correction.prompting, "generate_request", return_value=([], {})), patch.object(
+                    correction, "handle_label_errors"
+                ) as handle:
+                    correction.process_single_task((str(group), "Ex 1"), json.dumps(response))
+                handle.assert_not_called()
+                self.assertEqual(pdf.read_bytes(), b"original")
+                self.assertFalse(pdf.with_name("Ex 1_old.pdf").exists())
+                self.assertEqual(workspace.correction_file.read_bytes(), before)
+                self.assertEqual(correction.completed_tasks, [])
+                self.assertEqual(correction.results, prior)
+                self.assertIn(diagnostic, correction.errors_summary[0][0])
+
+    def test_valid_ids_can_be_returned_in_different_order(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            group = root / "Par label" / "Ex 1" / "Group_1.jpg"
+            group.parent.mkdir(parents=True)
+            group.touch()
+            atomic_write_json(group.with_suffix(".json"), [
+                ["37", 0, 500, 1], ["05", 550, 1000, 1],
+            ])
+            workspace = EvaluationWorkspace(root)
+            args = correction.build_parser().parse_args([str(root)])
+            correction.configure_runtime(workspace, [(str(group), "Ex 1")], args, api_client=Mock())
+            response = [{"id": pid, "result": {
+                "score": 4, "error": "", "feedback": [],
+            }} for pid in ["05", "37"]]
+            with patch.object(correction.prompting, "generate_request", return_value=([], {})):
+                correction.process_single_task((str(group), "Ex 1"), json.dumps(response))
+            self.assertEqual(correction.errors_summary, [])
+            self.assertEqual(correction.results["Ex 1"], [response])
+            self.assertEqual(correction.completed_tasks, [(str(group), "Ex 1")])
diff --git a/tests/test_cutleft_narrow_pages.py b/tests/test_cutleft_narrow_pages.py
new file mode 100644
index 0000000..8a23f47
--- /dev/null
+++ b/tests/test_cutleft_narrow_pages.py
@@ -0,0 +1,73 @@
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+import pymupdf
+from PIL import Image
+
+from copienator.commands import cutleft
+
+
+class NarrowPageCropTests(unittest.TestCase):
+    def test_mixed_pages_crop_narrow_margin_from_very_left(self):
+        normal = Image.new('RGB', (900, 600), 'red')
+        normal.paste('green', (100, 0, 400, 600))
+        narrow = Image.new('RGB', (450, 600), 'red')
+        narrow.paste('blue', (0, 0, 300, 600))
+        thin = Image.new('RGB', (200, 600), 'yellow')
+        with patch.object(cutleft, 'get_pdf_pages', return_value=[normal, narrow, thin]):
+            result = cutleft.process_single_pdf(Path('/tmp/no-original/Copy.pdf'))
+        _, images, schema = result
+        image = images[0]
+        self.assertEqual(schema['full_width_pages'], [3])
+        self.assertEqual(schema['columns_per_file'], [3])
+        self.assertEqual(image.size, (910, 600))
+        self.assertEqual(image.getpixel((0, 0)), (0, 128, 0))
+        self.assertEqual(image.getpixel((299, 0)), (0, 128, 0))
+        self.assertEqual(image.getpixel((300, 0)), (0, 0, 0))
+        self.assertEqual(image.getpixel((305, 0)), (0, 0, 255))
+        self.assertEqual(image.getpixel((604, 0)), (0, 0, 255))
+        self.assertEqual(image.getpixel((610, 0)), (255, 255, 0))
+        self.assertEqual(image.getpixel((809, 0)), (255, 255, 0))
+        self.assertEqual(image.getpixel((810, 0)), (255, 255, 255))
+        self.assertEqual(image.getpixel((909, 0)), (255, 255, 255))
+
+    def test_narrow_margin_can_be_shifted_and_enlarged(self):
+        normal = Image.new('RGB', (900, 600), 'white')
+        narrow = Image.new('RGB', (450, 600), 'red')
+        narrow.paste('blue', (50, 0, 450, 600))
+        with patch.object(cutleft, 'get_pdf_pages', return_value=[normal, narrow]):
+            result = cutleft.process_single_pdf(
+                Path('/tmp/no-original/Copy.pdf'), shift_offset=50, width_offset=100)
+        self.assertEqual(result[1][0].size, (805, 600))
+        self.assertEqual(result[1][0].getpixel((405, 0)), (0, 0, 255))
+        self.assertEqual(result[1][0].getpixel((804, 0)), (0, 0, 255))
+
+    def test_legacy_original_identifies_narrow_pages_without_normal_siblings(self):
+        with tempfile.TemporaryDirectory() as temporary:
+            root = Path(temporary)
+            originals = root / 'Copies Originales'
+            originals.mkdir()
+            with pymupdf.open() as document:
+                document.new_page(width=1191, height=842)
+                document.save(originals / 'Copy.pdf')
+            images = [Image.new('RGB', (900, 2339)), Image.new('RGB', (750, 2339))]
+            with patch.object(cutleft, 'get_pdf_pages', return_value=images):
+                result = cutleft.process_single_pdf(root / 'Copies' / 'Copy.pdf')
+            self.assertEqual(result[2]['full_width_pages'], [])
+            self.assertEqual(result[1][0].width, 2 * int((1191 / 2 * 200 / 72) // 3) + 5)
+
+    def test_small_main_split_adjustments_keep_margin_cropping(self):
+        images = [Image.new('RGB', (1600, 2339)), Image.new('RGB', (1694, 2339))]
+        with patch.object(cutleft, 'get_pdf_pages', return_value=images):
+            result = cutleft.process_single_pdf(Path('/tmp/no-original/Copy.pdf'))
+        self.assertEqual(result[2]['full_width_pages'], [])
+        self.assertEqual(result[1][0].width, 2 * (1694 // 3) + 5)
+
+    def test_fullpage_option_still_keeps_every_page_separately(self):
+        images = [Image.new('RGB', (900, 600)), Image.new('RGB', (450, 600))]
+        with patch.object(cutleft, 'get_pdf_pages', return_value=images):
+            result = cutleft.process_single_pdf(Path('/tmp/no-original/Copy.pdf'), max_per_file=1)
+        self.assertEqual([image.size for image in result[1]], [(900, 600), (450, 600)])
+        self.assertEqual(result[2]['columns_per_file'], [1, 1])
diff --git a/tests/test_gemini_config.py b/tests/test_gemini_config.py
index 06fd8ff..f5259e0 100644
--- a/tests/test_gemini_config.py
+++ b/tests/test_gemini_config.py
@@ -26,6 +26,7 @@ class GeminiConfigTests(unittest.TestCase):
         with tempfile.TemporaryDirectory() as directory:
             image = Path(directory) / "answer.jpg"
             image.write_bytes(b"image")
+            image.with_suffix(".json").write_text('[["01", 0, 400, 1.0, "Ex 1"]]')
             for level in ("minimal", "low", "medium", "high", None):
                 with self.subTest(level=level), patch.object(prompting, "make_prompt", return_value="Grade"):
                     _, config = prompting.generate_request(directory, image, "Ex 1", thinking_level=level)
diff --git a/tests/test_gui_core.py b/tests/test_gui_core.py
index 3530f31..2b4a6b2 100644
--- a/tests/test_gui_core.py
+++ b/tests/test_gui_core.py
@@ -1775,8 +1775,9 @@ class StandardCliTests(unittest.TestCase):
                 args,
                 api_client=Mock(),
             )
-            with patch.object(module.prompting, "make_prompt", return_value="prompt"):
+            with patch.object(module.prompting, "make_prompt", return_value="prompt") as make_prompt:
                 self.assertEqual(module.run_configured(args), 0)
+            make_prompt.assert_called_once_with(evaluation, "Ex 1", expected_ids=["01"])
             lines = (evaluation / "batch_requests_flash.jsonl").read_text().splitlines()
             self.assertEqual(len(lines), 1)
             self.assertEqual(json.loads(lines[0])["key"], str(image))
diff --git a/tests/test_prompting.py b/tests/test_prompting.py
index 9fac940..4d52b34 100644
--- a/tests/test_prompting.py
+++ b/tests/test_prompting.py
@@ -1,10 +1,26 @@
 import unittest
+import tempfile
+from pathlib import Path
 from unittest.mock import patch
 
 from copienator import prompting
 
 
 class PromptingTests(unittest.TestCase):
+    def test_live_prompt_includes_only_metadata_ids_in_order(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            image = Path(directory) / "Group_16.jpg"
+            image.write_bytes(b"image")
+            image.with_suffix(".json").write_text(
+                '[["22", 50, 834, 1], ["37", 904, 3250, 1], '
+                '["13", 3320, 4072, 1], ["05", 4142, 4892, 1]]'
+            )
+            contents, _ = prompting.generate_request(directory, image, "I)12)")
+        prompt = contents[0].parts[1].text
+        self.assertIn('["22", "37", "13", "05"]', prompt)
+        self.assertIn("exactement un résultat par identifiant", prompt)
+        self.assertIn("ignore les numéros manuscrits", prompt)
+
     def test_perspective_is_inserted_with_alternative_method_guidance(self) -> None:
         with patch.object(
             prompting, "get_label_text_content", return_value="Question"