[bug] badly formed help string

Describe the bug

Running

python -m olmocr.bench.benchmark --dir ./olmOCR-bench/bench_data

raises the following:

Traceback (most recent call last):
  File "/home/grossjct/miniconda3/envs/ocr-benchmark/lib/python3.14/argparse.py", line 1744, in _check_help
    formatter._expand_help(action)
    ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^
  File "/home/grossjct/miniconda3/envs/ocr-benchmark/lib/python3.14/argparse.py", line 672, in _expand_help
    return help_string % params
           ~~~~~~~~~~~~^~~~~~~~
ValueError: unsupported format character 'C' (0x43) at index 65

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/home/grossjct/repositories/olmocr/olmocr/bench/benchmark.py", line 554, in <module>
    main()
    ~~~~^^
  File "/home/grossjct/repositories/olmocr/olmocr/bench/benchmark.py", line 184, in main
    parser.add_argument(
    ~~~~~~~~~~~~~~~~~~~^
        "--confidence_level",
        ^^^^^^^^^^^^^^^^^^^^^
    ...<2 lines>...
        help="Confidence level for interval calculation (default: 0.95 for 95% CI).",
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/home/grossjct/miniconda3/envs/ocr-benchmark/lib/python3.14/argparse.py", line 1558, in add_argument
    self._check_help(action)
    ~~~~~~~~~~~~~~~~^^^^^^^^
  File "/home/grossjct/miniconda3/envs/ocr-benchmark/lib/python3.14/argparse.py", line 1746, in _check_help
    raise ValueError('badly formed help string') from exc
ValueError: badly formed help string

Versions

Python 3.14.3 annotated-doc==0.0.4 annotated-types==0.7.0 anthropic==0.89.0 anyio==4.13.0 argcomplete==3.6.3 attrs==26.1.0 awscli==2.33.2 beautifulsoup4==4.14.3 bleach==6.3.0 blinker==1.9.0 boto3==1.42.84 botocore==1.42.84 cached_path==1.8.10 certifi==2026.2.25 cffi==2.0.0 charset-normalizer==3.4.7 click==8.3.2 cryptography==46.0.6 defusedxml==0.7.1 distro==1.9.0 docstring_parser==0.17.0 eval_type_backport==0.3.1 fastjsonschema==2.21.2 filelock==3.25.2 Flask==3.1.3 fsspec==2026.3.0 ftfy==6.3.1 fuzzysearch==0.8.1 google-api-core==2.30.2 google-auth==2.49.1 google-cloud-core==2.5.1 google-cloud-storage==3.10.1 google-crc32c==1.8.0 google-genai==1.70.0 google-resumable-media==2.8.2 googleapis-common-protos==1.74.0 greenlet==3.3.2 h11==0.16.0 hf-xet==1.4.3 httpcore==1.0.9 httpx==0.28.1 huggingface_hub==1.9.0 idna==3.11 importlib_metadata==8.7.1 itsdangerous==2.2.0 Jinja2==3.1.6 jiter==0.13.0 jmespath==1.1.0 jsonpath-python==1.1.5 jsonschema==4.26.0 jsonschema-specifications==2025.9.1 jupyter_client==8.8.0 jupyter_core==5.9.1 jupyterlab_pygments==0.3.0 langcodes==3.5.1 lingua-language-detector==2.2.0 locate==1.1.1 lxml==6.0.2 markdown-it-py==4.0.0 markdown2==2.5.5 markdownify==1.2.2 MarkupSafe==3.0.3 mdurl==0.1.2 mistralai==2.3.0 mistune==3.2.0 msgpack==1.1.2 nbclient==0.10.4 nbconvert==7.17.0 nbformat==5.10.4 numpy==2.4.4 openai==2.30.0 opentelemetry-api==1.39.1 opentelemetry-semantic-conventions==0.60b1 orjson==3.11.8 packaging==26.0 pandocfilters==1.5.1 pillow==12.2.0 platformdirs==4.9.4 playwright==1.58.0 proto-plus==1.27.2 protobuf==7.34.1 pyasn1==0.6.3 pyasn1_modules==0.4.2 pycparser==3.0 pydantic==2.12.5 pydantic_core==2.41.5 pyee==13.0.1 Pygments==2.20.0 pypdf==6.9.2 pypdfium2==5.6.0 python-dateutil==2.9.0.post0 python-magic==0.4.27 PyYAML==6.0.3 pyzmq==27.1.0 RapidFuzz==3.14.3 referencing==0.37.0 regex==2026.4.4 requests==2.33.1 rich==13.9.4 rpds-py==0.30.0 rpm==4.20.1 s3transfer==0.16.0 sequence_align==0.2.0 shellingham==1.5.4 six==1.17.0 smart_open==7.5.1 sniffio==1.3.1 soupsieve==2.8.3 syntok==1.4.4 tenacity==9.1.4 tinycss2==1.4.0 tinyhost==0.4.18 tomlkit==0.14.0 tornado==6.5.5 tqdm==4.67.3 traitlets==5.14.3 typer==0.24.1 typing-inspection==0.4.2 typing_extensions==4.15.0 urllib3==2.6.3 wcwidth==0.6.0 webencodings==0.5.1 websockets==16.0 Werkzeug==3.1.8 wordfreq==3.1.1 wrapt==2.1.2 xmltodict==1.0.2 yq==3.4.3 zipp==3.23.0 zstandard==0.25.0