diff --git a/scripts/paycheck.py b/scripts/paycheck.py
index 6ee36f2..e199a7c 100755
--- a/scripts/paycheck.py
+++ b/scripts/paycheck.py
@@ -18,6 +18,10 @@
 
 
 # The default sizes of partitions, based on current partitioning practice.
+# TODO(garnold)(chromium:243559) we should stop using these values once
+# partition sizes are encoded in newly generated payloads; that said, we should
+# allow users to specify partition sizes on the command-line, so as to be able
+# to check older payloads.
 _DEFAULT_ROOTFS_PART_SIZE = 2 * 1024 * 1024 * 1024
 _DEFAULT_KERNEL_PART_SIZE = 16 * 1024 * 1024
 
diff --git a/scripts/update_payload/checker.py b/scripts/update_payload/checker.py
index eabcedb..18da5af 100644
--- a/scripts/update_payload/checker.py
+++ b/scripts/update_payload/checker.py
@@ -1095,6 +1095,9 @@
       assert self.payload_type, 'payload type should be known by now'
 
       # Part 3: examine rootfs operations.
+      # TODO(garnold)(chromium:243559) only default to the filesystem size if
+      # no explicit size provided *and* the partition size is not embedded in
+      # the payload; see issue for more details.
       report.AddSection('rootfs operations')
       total_blob_size = self._CheckOperations(
           self.payload.manifest.install_operations, report,
@@ -1104,6 +1107,7 @@
           0, False)
 
       # Part 4: examine kernel operations.
+      # TODO(garnold)(chromium:243559) as above.
       report.AddSection('kernel operations')
       total_blob_size += self._CheckOperations(
           self.payload.manifest.kernel_install_operations, report,