diff --git a/.github/actions/prose-gate/prose_lint.py b/.github/actions/prose-gate/prose_lint.py
index 2c87eb20a..ae4d23351 100755
--- a/.github/actions/prose-gate/prose_lint.py
+++ b/.github/actions/prose-gate/prose_lint.py
@@ -1568,7 +1568,7 @@ def resume_at(carry: Carried, line: str) -> tuple[Carried, int | None]:
 # A tool's name is anchored at the body's start, since a comment naming one mid-sentence is prose.
 NOT_PROSE = re.compile(
     r"^(?:!|\s*[-=#*/<>]+\s*$|ruff:|mypy:|(?i:flake8)[:=]|v\d+(?:\.\d+)*$"
-    r"|(?:(?i:noqa)|type:\s*ignore|pylint|shellcheck|markdownlint|omit from toc|prettier|eslint"
+    r"|(?:(?i:noqa|nopep8)|type:\s*ignore|pylint|shellcheck|markdownlint|omit from toc|prettier|eslint"
     r"|SPDX|Copyright)\b|(?i:c?spell|spell-?checker):)"
 )
 
@@ -1671,7 +1671,7 @@ def resume_at(carry: Carried, line: str) -> tuple[Carried, int | None]:
 # So a name here is exempt from that one rule, and a name in `NOT_PROSE` from all three.
 TOOL_DIRECTIVE = re.compile(
     r"^(?:syntax=|escape=|fmt:\s*(?:on|off|skip)\b|pragma:|nosec\b|checkov:|hadolint\b"
-    r"|renovate:|yaml-language-server:|-\*-\s*coding[:=]|pyright:|isort:|(?i:nopep8)\b"
+    r"|renovate:|yaml-language-server:|-\*-\s*coding[:=]|pyright:|isort:"
     r"|codespell:|doctest:)"
 )
 
diff --git a/tests/test_prose_lint.py b/tests/test_prose_lint.py
index 9f97db1d0..4f1b4f357 100755
--- a/tests/test_prose_lint.py
+++ b/tests/test_prose_lint.py
@@ -1592,6 +1592,8 @@ def test_a_directive_is_read_in_any_letter_case_its_tool_reads(self) -> None:
             ("tool.py", "# NoQA\n"),
             ("tool.py", "# NOPEP8\n"),
             ("tool.py", "# NoPep8: E501\n"),
+            ("tool.py", "# NOPEP8: E501. Another sentence follows.\n"),
+            ("tool.py", "# nopep8\n"),
             ("app.ts", "// cspell:ignore vendorid\n"),
             ("app.ts", "// CSPELL: ignore vendorid\n"),
             ("app.ts", "// spell-checker: disable\n"),