LaTeX Compile

Run the four-pass LaTeX build loop and report something a human can act on: the log tail, the page count, and the warnings that actually matter (undefined citations, overfull boxes, missing font shapes).

Boundaries

Do:

• Compile an existing .tex entry file into a PDF.
• Report exit code, page count, and extracted warning signals.
• Optionally enforce --min-pages / --min-refs as pre-compile gates.

Do not:

• Rewrite the user's .tex source. This skill only reads it.
• Inject an author/title line or assemble sibling abstract.tex / method.tex fragments — that was the upstream meta-skill's contract, not a general compiler's job.
• Claim a build succeeded without checking that the PDF actually exists.

Preflight

# 1. engine present?
Get-Command xelatex -ErrorAction SilentlyContinue
# 2. document present?
Get-Item .\paper\paper.tex
# 3. bibliography present (only needed for citations)?
Get-ChildItem .\paper\*.bib

If xelatex is missing, stop and give the install command (winget install MiKTeX.MiKTeX or choco install miktex on Windows; tlmgr/TeX Live elsewhere). Do not fall back to a different engine silently — pdflatex cannot render CJK without extra packages.

Run

python scripts\compile.py .\paper\paper.tex
python scripts\compile.py .\paper\paper.tex --engine pdflatex --no-bibtex
python scripts\compile.py .\paper\paper.tex --min-pages 10 --min-refs 20
python scripts\compile.py .\paper\paper.tex --bib .\paper\refs.bib --tail-lines 80

What the script does

1. Preflight: .tex exists, engine on PATH, .bib located.
2. Optional citation gate: undefined \cite keys and --min-refs are checked before spending build time.
3. Build passes: xelatex → bibtex → xelatex → xelatex. xelatex returns 0 even on minor issues, so only the final pass is allowed to fail hard.
4. PDF existence check, page-count parse from the log, warning extraction.
5. stdout stays a single clean line (Compiled: <pdf> (<n> KB, pages=<n>)); the verbose log tail and warnings go to stderr.

Exit codes

Common traps

• Stale .aux / .bbl: if citations look wrong after a .bib edit, delete *.aux / *.bbl and rebuild — the four-pass loop alone cannot always recover a corrupt aux.
• bibtex fails but PDF exists: reported as a warning, not a hard failure. Check the warning list for bibtex: lines before telling the user citations resolved.
• CJK renders as boxes: the engine lacks a CJK font mapping. Add \usepackage{xeCJK} + \setCJKmainfont{...} (or fontspec with a CJK TTF) to the preamble; the script does not inject it.
• Windows PATH: a freshly installed MiKTeX/TeX Live needs a new shell. If Get-Command xelatex works but the script reports exit 3, pass the absolute engine path by putting its bin on PATH first.
• Overfull hbox floods the tail: harmless warnings. Do not "fix" them by trimming the user's prose unless asked.

Related skills

• ../research-paper-writing/SKILL.md — drafting and polishing the manuscript itself.
• ../arxiv/SKILL.md — fetching papers and generating BibTeX entries.