Compile Latex

compile-latex

Compile a .tex, parse the log into a ranked report with correct file:line attribution, and diff it against the previous build. The default is compile-and-report only; nothing in the source is edited unless --figures is passed.

Parsing detail (package tables, log regexes, file-stack rules, box thresholds, state schema) is in references/log-patterns.md. Read it before steps 3 through 5. Diff-vs-last-compile is adapted from compiledeck in scunning1975/MixtapeTools.

Options

Resolving the file

No config file. In order: use an absolute or cwd-relative path if given; otherwise Glob ~/Library/CloudStorage/Dropbox*/Apps/Overleaf/*/**/<name>.tex and, if a project name was mentioned, filter to that project directory; otherwise Glob *.tex in the cwd and pick the one with \documentclass. Ask only if that leaves zero or several plausible masters.

A .tikz path, or an inline TikZ block pasted into the request, has no master to compile. Take it as --figures on that one block: skip steps 1 through 5 and go to step 6 with the block as the single unit, wrapped as step 6 describes. There is nothing to splice back, so the approved source goes to --output (default $RUN/final.tex) and the path is reported.

Step 0, pre-flight

1. Read the master.
2. Conflicted-copy guard. This setup assumes these projects sync through Dropbox (adjust to your machine), so compiling next to a stale sibling means reporting errors the user already fixed elsewhere. Glob the project directory recursively for *conflicted copy* (.tex, .bib, .sty, .cls). If any exist, stop and list them with mtimes so the user can resolve the conflict. --force overrides.
3. --clean / --clean-all: run latexmk -c -outdir=<outdir> <file> or latexmk -C -outdir=<outdir> <file> and stop.
4. latexmk is at /Library/TeX/texbin/latexmk on a MacTeX install. If it is missing from PATH, prepend /Library/TeX/texbin before failing with SETUP_MISSING:latexmk. With --figures, also check gs (e.g. /usr/local/bin/gs); if absent, report SETUP_MISSING:gs and skip the figure pass, keeping the compile report.

Step 1, detect engine and bib backend

Read the preamble plus any \input'd preamble file (§6 of the reference). A % !TEX program = magic comment wins. Otherwise fontspec / unicode-math / \setmainfont / xeCJK / ctex implies xelatex; \directlua / luacode implies lualatex; else pdflatex. --engine= overrides both.

Bib backend, unless --no-bib: biblatex or \addbibresource means biber; natbib plus \bibliographystyle means bibtex. Warn on a mismatch (biblatex loaded with a leftover \bibliographystyle, or \addbibresource with no biblatex).

Print the detection before compiling:

File:   <path>
Engine: xelatex  (\setmainfont in preamble)
Bib:    biber    (\addbibresource)
Outdir: build/

Step 2, compile

latexmk -f "$ENGINE_FLAG" -interaction=nonstopmode -synctex=1 -outdir=<outdir> <file>

ENGINE_FLAG comes from the step-1 detection: -pdf (pdflatex), -pdfxe (xelatex), -pdflua (lualatex). -f matters: without it latexmk stops at the first failing pass, so the log holds one error instead of all of them. Never pass -halt-on-error. Add -bibtex- for --no-bib. A nonzero exit code is expected on a failed document and is not a tooling failure; parse the log regardless.

Step 3, parse the log

Read <outdir>/<jobname>.log and run the file-stack tracker from §3 so every file:line lands on the right \input'd sub-file rather than the master. The tracker must push a placeholder for non-path ( as well, otherwise the parens inside ordinary messages (Overfull \hbox (15.83003pt too wide)) pop real files off the stack and every subsequent attribution is wrong.

Extract blocking errors (! ... plus the following l.<N>), undefined refs/cites (§4), and boxes (§5).

Step 4, rank and report

Lead with one verdict line, BUILD OK / BUILD OK (with warnings) / BUILD FAILED (N blocking), and the PDF path. Then, in this fixed order:

1. Blocking errors. <file>:<line> plus the ! ... message. For Undefined control sequence, look the token up in §1 and suggest the \usepackage. For Environment X undefined, use the environment table in §1. For a missing .sty, print the tlmgr line from §2 for the user to run (MacTeX's tree is root-owned, so it needs sudo; never run it unprompted). Collapse cascades per §1: one undefined environment produces two or three downstream errors that vanish once the root cause is fixed.
2. Undefined refs and cites, split into two lists, keys with input lines. Only report what survives the final pass (§4).
3. Boxes, gated: overfull above --box-threshold, underfull at badness >= 5000. Worst 10 sorted by severity, then +K more.

Below-threshold and font/rerun-check noise is dropped silently.

Step 5, diff vs last compile

State lives at ~/.claude/state/compile-latex/<hash>/last.json, where <hash> is sha1(abspath)[:12]. Load it, diff the new ref/cite/box sets, and report deltas (+2 overfull, -1 undefined ref since last compile). Box identity is file:lines:kind, not the pt value, so a reflow of the same box is not counted as new. Write the new state atomically (tmp file plus rename); the Write tool creates missing parent directories, but a Bash-side write needs a mkdir -p first, since ~/.claude/state/ may not exist yet. With no baseline, note first compile (no baseline) and just write. Schema in §8.

Step 6, figures (opt-in, --figures only)

Runs only under --figures, and only when the build was clean and figures exist. Extract, compile, render, review, apply, repeat, until the tikz-reviewer agent answers APPROVED or --max-iter rounds are gone. The agent does the visual judgment and it judges from pixels, never from reading source. Loop concept borrowed from Scott Cunningham's /tikz collision audit in MixtapeTools.

6.1 Extract

Grep the master and its \input'd files for \begin{tikzpicture} and pgfplots \begin{axis} / \begin{groupplot} blocks (§7). Treat the outermost tikzpicture as the unit. For each block, record the file, the exact body text, and sha1(body).

Harvest the parent preamble's \usepackage / \usetikzlibrary / \usepgfplotslibrary / \pgfplotsset / \definecolor / \colorlet / \newcommand / \def / \tikzset lines into a standalone wrapper, so colors and macros resolve and the crop is the drawing rather than a page:

\documentclass[tikz,border=4pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta,positioning,calc,decorations.pathreplacing,shapes.geometric}
\usepackage{amsmath,amssymb}
% --- harvested preamble lines here ---
\begin{document}
% --- the captured block here ---
\end{document}

A block that has to stay in place (a figure that \inputs a shared preamble) compiles where it lives with the build diverted by -outdir. Record which case each block is, since it sets the render DPI.

6.2 Compile the figure

Every round of every figure gets its own directory, so nothing is clobbered and the history stays inspectable if the loop stalls. That also keeps .aux churn out of the user's project tree and out of Dropbox sync.

export PATH="/Library/TeX/texbin:$HOME/.local/bin:$PATH"
RUN="$HOME/.claude/state/compile-latex/figures/$(date +%Y%m%d-%H%M%S)"
mkdir -p "$RUN/fig-01/iter-01"   # and iter-NN at the top of every later round
cd "$RUN/fig-01/iter-NN" && latexmk -pdf -interaction=nonstopmode -halt-on-error diagram.tex

-halt-on-error is right here and wrong in step 2. A figure that will not build has one error worth reading and the next round needs it now, whereas the whole document wants every error at once. On a non-zero exit, pull the message:

grep -A2 '^! ' diagram.log | head -3

The l.<N> line follows the bang line. Do not add -m1: BSD grep stops reading at the match and drops the trailing context, so you get the message with no line number. Report COMPILE_FAILED:<line>:<message> for that figure and move to the next one. If the log names a missing .sty, retry once with tectonic -X compile diagram.tex --outdir <dir>, which fetches it; the outdir must already exist. Never render a stale PDF from the previous round.

6.3 Render to PNG

gs -dSAFER -dBATCH -dNOPAUSE -sDEVICE=png16m -r200 \
   -dTextAlphaBits=4 -dGraphicsAlphaBits=4 \
   -sOutputFile=page-%d.png diagram.pdf

The %d writes one PNG per page. The alpha-bits flags are anti-aliasing; without them thin rules and small type alias badly and the reviewer reports artifacts as real defects. On a full document, review only the page carrying the figure.

Pick DPI from the canvas. -r200 suits a full page (a Beamer frame lands near 1000px wide) and -r300 a dense one, but a cropped standalone PDF is often two inches across, where -r200 yields about 390px and millimetre clearances become unjudgeable. Start those at -r600, then confirm:

long=$(sips -g pixelWidth -g pixelHeight page-1.png | awk '/pixel(Width|Height)/{print $2}' | sort -rn | head -1)

Under 700, re-render at double the DPI; over 2400, halve it. Correct once, do not loop. If gs exits non-zero or the PNG is missing or empty, surface RENDER_FAILED:<message> for that figure and move on. Ghostscript is the rasterizer here. This setup assumes no Homebrew and no poppler, so pdftoppm and pdftotext do not exist and nothing should reach for them; adjust to your machine.

6.4 Review

Launch the tikz-reviewer agent (subagent_type: "tikz-reviewer") with absolute paths: the PNG, the current .tex, the round number against --max-iter, and the goal from --goal or the figure's \caption. Tell it to read the PNG and judge from the pixels.

Its output contract is in ~/.claude/agents/tikz-reviewer.md: either the bare word APPROVED, or a numbered list of severity-tagged findings each carrying its arithmetic and an exact search-and-replace. It already knows this, so do not restate the contract in the prompt.

6.5 Apply or finish

On APPROVED, go to 6.6. Otherwise apply each numbered item with Edit, using the exact old_string / new_string given. Surgical replacements only; never regenerate the block. Copy the edited file into the next round's directory and return to 6.2.

Before applying, diff the list against the previous round's. A verbatim repeat means the loop is oscillating between two fixes, so stop early and report that instead of burning the remaining rounds. A reply that is neither APPROVED nor a parseable list earns one re-prompt ("Please respond in the required format"); on a second drift, stop and surface the raw reply.

At --max-iter without approval, surface the last PNG, the outstanding objections, and the in-progress source, and leave that block unspliced.

With several figures, run the loops in lockstep: compile and render all of them, launch every reviewer call for that round in one message, then apply. A figure that approves drops out of later rounds.

6.6 Splice back and rebuild

Splice only on a verified anchor. Re-Read the source file, confirm the captured body still appears exactly once and its sha1 is unchanged, then Edit with that body as old_string. If it is missing, appears more than once, or the hash moved, skip it and report not spliced (source changed). Strip the wrapper first; keep the surrounding figure env, \caption, \label, \centering, and any \resizebox / \adjustbox.

Recompile once. Report which blocks changed and what each round fixed, and for every block that did not finish, the round it reached and why it stopped. To inspect the compiled document's text, run ~/.claude/assets/bin/pdfread.py text <outdir>/<jobname>.pdf. This setup assumes the Read tool cannot open a PDF (no pdftoppm; adjust to your machine).

Step 7, cleanup

Aux files stay in <outdir>/. Mention --clean / --clean-all as the way to wipe them; leave the PDF. For a live rebuild loop tell the user to run latexmk -pvc -outdir=<outdir> <file> themselves.

Failure modes

Examples

compile-latex main.tex
→ BUILD FAILED (1 blocking)
  sections/results.tex:212  Undefined control sequence \toprule
    fix: \usepackage{booktabs}
→ 1 undefined cite: Smith2020
→ since last compile: +0 boxes

compile-latex "Algorithmic Pricing Manuscript" --box-threshold=2pt
→ BUILD OK (with warnings) | build/main.pdf
→ 3 overfull >2pt (worst: sections/model.tex:88, 18.4pt) | +1 since last compile