latex-compile

name	latex-compile
description	Compile a paper in `<target>/tex/` to PDF. Runs pdflatex → bibtex → pdflatex → pdflatex, parses the .log for errors, surfaces a focused error report. Use whenever the user says "compile", "build the PDF", or after any non-trivial edit to the .tex sources.

latex-compile

Invocation

User says one of: "compile", "compile the paper", "build the PDF", "rerun latex".

You should also invoke this skill automatically after every successful pass through the gatekeeper, to confirm the paper still builds.

What this skill does

0. Pre-compile sanitation (harvest-junk guard). Before building, scan main.tex for two artifacts that creep in when a .tex was harvested from an LLM/browser response rather than authored in place:

   • Trailing junk after the document ends: any non-whitespace content after the first \end{document}. This is almost always assistant chatter that followed the code block (e.g. lines like G. appendix.tex patch, Notes, No new citation keys were added…). LaTeX silently ignores it, so the PDF still builds and the problem goes unnoticed — but it pollutes the submission source.
   • Leading junk before the preamble: any non-whitespace content before the first \documentclass (e.g. a ```latex fence or a "Here is the file:" preamble line).

   If either is present: save a one-time backup main.tex.bak (only if it doesn't already exist), strip the offending region, and report it — e.g. "Stripped 6 lines of harvest junk after \end{document} (backup at main.tex.bak)." Do not touch anything between \documentclass and \end{document} — that is the real document. This is the one sanctioned exception to "does not edit .tex sources": removing text outside the document body is not editing the paper.

   One-liner that does it (POSIX sed): sed -n '/\\documentclass/,/\\end{document}/p' main.tex extracts exactly the document; compare line counts to detect junk before acting.

1. Identify the target. If the user names a slug, use <target>/tex/. Otherwise look for the most-recently-edited paper directory.

2. From that tex/ directory, run the four-pass build:

   pdflatex -interaction=nonstopmode -halt-on-error main.tex
   bibtex main
   pdflatex -interaction=nonstopmode main.tex
   pdflatex -interaction=nonstopmode main.tex
   

   If latexmk is available, prefer:

   latexmk -pdf -interaction=nonstopmode -halt-on-error main.tex
   

3. Parse main.log. Report:

   • Errors (lines starting !) — show 3 lines of source context + the error message.
   • Undefined references — list them.
   • Undefined citations — list them, cross-check against refs.bib. If a key is in refs.bib but bibtex didn't pick it up, suggest rerunning bibtex.
   • Overfull / underfull boxes — summarize counts only; do not fix.
   • Final PDF path on success.

Reporting style

• On success: one line — "Built <target>/tex/main.pdf (N pages)." plus warning counts.
• On failure: lead with the first error, show source context, suggest the likely fix.
• Never claim success unless main.pdf exists and the log's final status confirms it.

Failure modes to watch for

• Missing econometrica.bst — for Econometrica submission, swap the official .bst from econometricsociety.org. Default template uses natbib + plainnat-compatible fallback.
• Stale aux files — if errors look like ghosts of removed labels, run rm *.aux *.bbl *.blg and rebuild.
• Proofs not found — if \input{../proofs/...} fails because no file is there, the user hasn't dropped in their pre-baked proofs yet. Suggest they do so.

What this skill does NOT do

• Does not edit .tex sources.
• Does not rebuild figures.
• Does not push to remote or deploy.
• Does not touch anything in proofs/.