How to pass `hyphenpenalty` as a CLI parameter to Pandoc?

I want to convert MD to PDF with Pandoc and pdflatex:

pandoc \
  "$md_file" \
  --pdf-engine=pdflatex \
  --variable=geometry:a4paper \
  --variable=fontsize=12pt \
  --output "${md_file%.md}.pdf"

How do I disable hyphenation using a CLI paramter?

I've tried to set it within the markdown file, as a YAML metadata block, and it's working:

---
header-includes: |
  \hyphenpenalty=10000
  \exhyphenpenalty=10000
---
The rest of the markdown file…

But… I want the settings for multiple files and I do not want to "hardcode" them inside the markdown file, so I've extracted the above to a dedicated pdf_config.yml file, and it is also working:

header-includes: |
  \hyphenpenalty=10000
  \exhyphenpenalty=10000  

pandoc
  --metadata-file ./pdf_config.yml \

Finally, I do not want an extra YAML file -> I want everything in my bash script -> so, I want to pass the metadata by a CLI parameter. I'v tried multiple variations of the below, with no success:

pandoc
  --metadata=header-includes:hyphenpenalty=10000 \
  --metadata=header-includes:exhyphenpenalty=10000 \

Error producing PDF.
! LaTeX Error: Missing \begin{document}.
See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...                                              
                                                  
l.45 h

Instead of setting the header-includes metadata value, set the variable of the same name instead:

pandoc -V header-includes="\\hyphenpenalty=10000 \\exhyphenpenalty=10000" ...

This will be inserted into the document verbatim.

You should pass the HY register with the value 0 with the -rHY=0 command line flag.

Then pass the metadata by a CLI parameter.