diff --git a/docs/index.html b/docs/index.html
index 65672299..48b14f93 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -820,7 +820,10 @@ <h1>Context</h1>
 ...             max_length=100000,
 ...             max_groups=100,
 ...         ),
-...         dp.polars.Margin(by=([&quot;grade_bin&quot;] + list({}.keys())), invariant=&quot;keys&quot;),
+...         dp.polars.Margin(
+...             by=([&quot;grade_bin&quot;] + list({}.keys())),
+...             invariant=&quot;keys&quot;,  # Consider the bin values to be public information.
+...         ),
 ...     ],
 ... )
 </code></pre>
diff --git a/docs/index.md b/docs/index.md
index 45246300..3a315bc3 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -568,7 +568,10 @@ Next, we'll define our Context. This is where we set the privacy budget, and set
 ...             max_length=100000,
 ...             max_groups=100,
 ...         ),
-...         dp.polars.Margin(by=(["grade_bin"] + list({}.keys())), invariant="keys"),
+...         dp.polars.Margin(
+...             by=(["grade_bin"] + list({}.keys())),
+...             invariant="keys",  # Consider the bin values to be public information.
+...         ),
 ...     ],
 ... )
 
diff --git a/dp_wizard/utils/code_generators/abstract_generator.py b/dp_wizard/utils/code_generators/abstract_generator.py
index 6ee807d0..2818f6f3 100644
--- a/dp_wizard/utils/code_generators/abstract_generator.py
+++ b/dp_wizard/utils/code_generators/abstract_generator.py
@@ -140,7 +140,10 @@ def basic_template(GROUPS, MAX_ROWS):
             )
 
         def bin_template(GROUPS, BIN_NAME):
-            dp.polars.Margin(by=([BIN_NAME] + list(GROUPS.keys())))
+            dp.polars.Margin(
+                by=([BIN_NAME] + list(GROUPS.keys())),
+                invariant="keys",  # Consider the bin values to be public information.
+            )
 
         margins = [
             DefaultsTemplate(basic_template)
diff --git a/tests/test_misc.py b/tests/test_misc.py
index 7b58235c..3f72488d 100644
--- a/tests/test_misc.py
+++ b/tests/test_misc.py
@@ -84,6 +84,7 @@ def get_file_paths() -> list[Path]:
         for path in package_root.parent.iterdir()
         if not (
             path.match("*venv*")
+            or path.name.startswith(".coverage")
             or path.name
             in [
                 "docs",