diff --git a/py/api/images.py b/py/api/images.py
index f5a02bb..5adb8d5 100644
--- a/py/api/images.py
+++ b/py/api/images.py
@@ -2351,6 +2351,23 @@ class ImageRoutesMixin:
             self.logger.warning("Workspace link summaries could not be read")
             return {}
 
+    def _card_parse(self, path: Path, records: dict | None) -> tuple:
+        """One card's ``(seed, parsed positive)``; ``(None, None)`` on any error.
+
+        One file's unexpected parse failure must not fail the whole page: its
+        card shows no seed and withholds a first-line title.
+        """
+        try:
+            params = header_params(records)
+            return card_seed(params), parsed_positive(params)
+        except Exception:
+            self.logger.warning(
+                "Workspace card facts could not be parsed for %s",
+                path.name,
+                exc_info=True,
+            )
+            return None, None
+
     def _format_workspace_page(
         self, page: list[tuple], *, linked: bool = True
     ) -> list[dict]:
@@ -2384,10 +2401,10 @@ class ImageRoutesMixin:
                 continue
             # Parsed after the handle closes, so a concurrent rename or delete
             # (which Windows refuses on open files) is not held up by it.
-            params = header_params(records)
-            image["seed"] = card_seed(params)
+            seed, positive = self._card_parse(path, records)
+            image["seed"] = seed
             summary = summaries.get(str(path)) or _unavailable_link()
-            image["linked"] = _card_link(summary, parsed_positive(params))
+            image["linked"] = _card_link(summary, positive)
         if linked:
             # Image cards carry the star; Library previews show none.
             favorites = self._workspace_favorites(page)
diff --git a/tests/test_api_workspace_images.py b/tests/test_api_workspace_images.py
index 5770f7e..4f73b3c 100644
--- a/tests/test_api_workspace_images.py
+++ b/tests/test_api_workspace_images.py
@@ -643,6 +643,48 @@ class TestWorkspaceImages(ImageAPITestCase):
         else:
             self.assertEqual(shown, {"status": "known", "value": card})
 
+    async def test_unbounded_digit_string_seed_still_lists(self):
+        records_png(
+            self.output_dir / "huge.png", seeded_records("a fox", "9" * 5000), 200
+        )
+        records_png(self.output_dir / "ok.png", seeded_records("a fox", 5))
+        response, data = await self.get()
+        self.assertEqual(response.status, 200, data)
+        items = {item["filename"]: item for item in data["images"]}
+        self.assertIsNone(items["huge.png"]["seed"])
+        self.assertEqual(items["ok.png"]["seed"], "5")
+
+    async def test_one_cards_parse_error_spares_the_page(self):
+        prompt = self._save_prompt("a fox")
+        for name, mtime in (("bad.png", 200), ("ok.png", 100)):
+            path = records_png(
+                self.output_dir / name, seeded_records("a fox", 5), mtime
+            )
+            self.api.db.link_image_to_prompt(prompt, str(path))
+        real_parse = header_params_of_images()
+
+        def parsing(info):
+            if parsing.calls == 0:
+                parsing.calls += 1
+                raise RuntimeError("unexpected parser bug")
+            return real_parse(info)
+
+        parsing.calls = 0
+        with (
+            patch("py.api.images.header_params", side_effect=parsing),
+            self.assertLogs(self.api.logger, "WARNING") as logged,
+        ):
+            response, data = await self.get()
+        self.assertEqual(response.status, 200, data)
+        items = {item["filename"]: item for item in data["images"]}
+        self.assertIsNone(items["bad.png"]["seed"])
+        self.assertIsNone(items["bad.png"]["linked"]["title"])
+        self.assertEqual(items["bad.png"]["linked"]["status"], "linked")
+        self.assertEqual(items["ok.png"]["seed"], "5")
+        self.assertEqual(items["ok.png"]["linked"]["title"], "a fox")
+        self.assertNotIn("unexpected parser bug", json.dumps(data))
+        self.assertIn("unexpected parser bug", "\n".join(logged.output))
+
     async def test_library_previews_skip_card_facts(self):
         records_png(self.output_dir / "a.png", seeded_records("a fox", 5))
         page = await self.api._collect_output_images(
diff --git a/tests/test_card_seed.py b/tests/test_card_seed.py
index 4f73396..466c92c 100644
--- a/tests/test_card_seed.py
+++ b/tests/test_card_seed.py
@@ -165,6 +165,22 @@ class CardSeed(unittest.TestCase):
                 self.assertEqual(card_seed({"seed": value}), str(value))
         self.assertEqual(card_seed({"seed": "18446744073709551616"}), str(2**64))
 
+    def test_digit_string_seed_is_bounded(self):
+        # 2**64 has 20 digits; a longer string is no seed, and an unbounded one
+        # must not reach int() (Python's int max-str-digits raises ValueError).
+        self.assertEqual(card_seed({"seed": "9" * 20}), "9" * 20)
+        self.assertEqual(card_seed({"seed": "-" + "9" * 20}), "-" + "9" * 20)
+        self.assertIsNone(card_seed({"seed": "1" * 21}))
+        self.assertIsNone(card_seed({"seed": "9" * 5000}))
+        self.assertIsNone(info_seed(graph(seeded("9" * 5000))))
+
+    def test_seed_conversion_error_gives_none(self):
+        class Huge(int):
+            def __str__(self):
+                raise ValueError("Exceeds the limit for integer string conversion")
+
+        self.assertIsNone(card_seed({"seed": Huge(5)}))
+
     def test_workflow_only_record(self):
         case = next(
             case
diff --git a/utils/card_seed.py b/utils/card_seed.py
index c92493b..5fd0ebb 100644
--- a/utils/card_seed.py
+++ b/utils/card_seed.py
@@ -20,12 +20,21 @@ from .generation_params import (
 )
 from .inspection_response import project_graph
 
-__all__ = ["MAX_RECORD_BYTES", "card_seed", "header_params", "parsed_positive"]
+__all__ = [
+    "MAX_RECORD_BYTES",
+    "MAX_SEED_DIGITS",
+    "card_seed",
+    "header_params",
+    "parsed_positive",
+]
 
 # Each record is parsed only up to this many UTF-8 bytes; past it, nothing is read.
 MAX_RECORD_BYTES = 2 * 1024 * 1024
 _RECORD_KEYS = ("prompt", "workflow")
-_INTEGER = re.compile(r"-?[0-9]+\Z")
+# A digit-string seed has at most this many digits (2**64 has 20). Longer text
+# is no seed, and never reaches int(), whose max-str-digits guard raises.
+MAX_SEED_DIGITS = 20
+_INTEGER = re.compile(r"-?[0-9]{1,%d}\Z" % MAX_SEED_DIGITS)
 
 
 def _utf8_size_over(text: str, limit: int) -> bool:
@@ -76,18 +85,23 @@ def card_seed(params: dict | None) -> str | None:
     Always text: ``JSON.parse`` in the browser rounds a number past 2**53, and
     ComfyUI's randomized seeds are often that large. The projection carries
     integers beyond 2**53 as their exact digits, so a digit string is the
-    recorded seed (the inspector shows it too). A placeholder, other text, a
-    boolean or a decimal gives None.
+    recorded seed (the inspector shows it too), up to ``MAX_SEED_DIGITS``
+    digits. A placeholder, other or longer text, a boolean or a decimal gives
+    None.
     """
     if not isinstance(params, Mapping):
         return None
     value = params.get("seed")
     if isinstance(value, bool):
         return None
-    if isinstance(value, int):
-        return str(value)
-    if isinstance(value, str) and _INTEGER.match(value):
-        return str(int(value))
+    try:
+        if isinstance(value, int):
+            return str(value)
+        if isinstance(value, str) and _INTEGER.match(value):
+            return str(int(value))
+    except ValueError:
+        # Python's integer string conversion limit: no seed, never a 500.
+        return None
     return None