diff --git a/.github/workflows/documentation.yaml b/.github/workflows/documentation.yaml
index 702a275..0579c57 100644
--- a/.github/workflows/documentation.yaml
+++ b/.github/workflows/documentation.yaml
@@ -17,7 +17,7 @@ jobs:
           python -m pip install -r docs/requirements.txt --no-deps
       - name: Build documentation
         run: |
-          python -m sphinx -b html -aE -n -W --keep-going docs/source docs/build
+          python -Werror -m sphinx -b html -aE -n -W --keep-going docs/source docs/build
       - name: Check external links
         run: |
           python -m sphinx -b linkcheck docs/source docs/build
diff --git a/cspell.config.yaml b/cspell.config.yaml
index 49600f7..3e90a39 100644
--- a/cspell.config.yaml
+++ b/cspell.config.yaml
@@ -4,6 +4,7 @@ useGitignore: true
 ignorePaths:
   - tests
   - requirements*.txt
+  - .github/workflows/*
   - .pre-commit-config.yaml
   - .pre-commit-hooks/*
 dictionaries:
diff --git a/docs/source/extensions/cli.py b/docs/source/extensions/cli.py
index 3ebd701..b05c487 100644
--- a/docs/source/extensions/cli.py
+++ b/docs/source/extensions/cli.py
@@ -65,7 +65,7 @@ def run(self) -> list[nodes.Node]:
             for positional in command.positional_arguments:
                 alias_paragraph = nodes.paragraph("", "", nodes.literal("", positional.name))
                 description_paragraph = nodes.paragraph("", positional.description or "")
-                description_paragraph.set_class("cli-option-description")
+                description_paragraph["classes"].append("cli-option-description")
                 command_section.extend([alias_paragraph, description_paragraph])
 
             for option in command.options:
@@ -75,7 +75,7 @@ def run(self) -> list[nodes.Node]:
                     alias_nodes.append(nodes.Text(", "))
                 alias_paragraph = nodes.paragraph("", "", *alias_nodes[:-1])
                 description_paragraph = nodes.paragraph("", option.description or "")
-                description_paragraph.set_class("cli-option-description")
+                description_paragraph["classes"].append("cli-option-description")
                 command_section.extend([alias_paragraph, description_paragraph])
 
             nodes_to_return.append(command_section)