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Configuration

Badness is configured through a badness.toml file. All keys are optional and spelled in kebab-case; an unknown key or section is a hard error, not a silent no-op. Run badness init to write a commented starter file showing every key at its default.

# Gitignore-style patterns to skip during directory discovery.
# exclude = [".git/"]
# extend-exclude = []

[format]
# line-width = 80
# indent-width = 2
# item-indent = "hang"  # hang | indent | none
# wrap = "reflow"  # reflow | stable | sentence | semantic | preserve
# line-ending = "auto"  # auto | lf | crlf | native

[lint]
# select = ["..."]  # if set, only these rules run
# ignore = []       # rules to disable

Discovery

For each input, Badness walks from the file’s directory upward and uses the first badness.toml it finds. The walk stops at a directory containing a .git entry (the repository root), so a config file outside your repository is never picked up.

If no project file is found, Badness next checks the BADNESS_CONFIG environment variable. When set (and non-empty), it names a config file to use instead of the global user config below—handy for keeping one config on a synced drive and pointing every machine at it. A set BADNESS_CONFIG shadows the global config entirely.

If BADNESS_CONFIG is unset, badness falls back to a global user config: the first existing file among

  1. $XDG_CONFIG_HOME/badness/config.toml
  2. ~/.config/badness/config.toml
  3. the platform config directory (%APPDATA%\badness\config.toml on Windows, ~/Library/Application Support/badness/config.toml on macOS)

The BADNESS_CONFIG and global files use the same schema as a project badness.toml and are whole-file fallbacks, never merged with a project config. Relative exclude patterns in them resolve against the working directory (CLI) or the document’s directory (language server) rather than the config’s own directory. The language server uses the same resolution, so both are easy ways to set editor-wide defaults such as wrap = "preserve" (an edit is picked up when the server restarts). If none of these files is found, built-in defaults apply.

Two global CLI flags override discovery:

  • --config <PATH> uses that file instead of discovering one.
  • --no-config ignores any project, BADNESS_CONFIG, or global file and uses built-in defaults.

CLI flags for individual options (--line-width, --wrap, --select, etc.) override the corresponding config values for a single run.

Editor support

Badness publishes a JSON Schema for badness.toml so editors with TOML support can provide key and value completion, hover documentation, and validation.

Schema URL: https://badness.dev/badness.schema.json

The schema is generated from the configuration types and checked against them in the test suite. The version at the URL tracks the latest released version of Badness.

VS Code (Even Better TOML)

With the Even Better TOML extension installed, add this association to your user or workspace settings.json:

{
  "evenBetterToml.schema.associations": {
    "^(.*/)?badness\\.toml$": "https://badness.dev/badness.schema.json"
  }
}

Inline #:schema directive

TOML tooling that supports inline schema directives can select it from the configuration file itself:

#:schema https://badness.dev/badness.schema.json

This is also useful for the global user configuration, whose generic config.toml file name should not be associated with Badness automatically.

Other editors

Any editor or language server that consumes JSON Schemas—including Helix, Neovim with taplo-lsp, Zed, and IntelliJ—can use the same URL through its TOML schema settings.

Top level

exclude

Gitignore-style patterns to exclude from directory discovery, resolved relative to the directory containing the badness.toml. Excludes apply to both format and lint, which share one file walk, so this is a top-level key rather than a [format] option.

When set, this replaces the built-in default set ([".git/"]); use extend-exclude to add patterns without restating the defaults. Patterns given with the --exclude CLI flag are always added on top.

Default value: [".git/"]

Type: array of strings

Example:

exclude = ["vendor/", "old-drafts/"]

extend-exclude

Gitignore-style patterns added in addition to the base set selected by exclude (the built-in defaults when exclude is unset). Use this to skip a few extra paths without replacing the defaults.

Default value: []

Type: array of strings

Example:

extend-exclude = ["build/"]

[format]

Options for badness format. Each mirrors a CLI flag of the same name, which takes precedence for a single run.

line-width

Maximum line width before the formatter breaks a line. Must be between 1 and 1000.

Default value: 80

Type: integer

Example:

[format]
line-width = 100

indent-width

Spaces per indent step. Must be between 1 and 1000.

Default value: 2

Type: integer

Example:

[format]
indent-width = 4

item-indent

How continuation lines in list items are indented relative to the \item command.

ModeBehavior
hangAlign under the body following a bare \item (the default).
indentAdd one indent-width step from the \item column.
noneAlign with the \item command.

Labels and Beamer overlays do not widen the hang offset, so items retain one continuation edge regardless of marker width.

Default value: "hang"

Type: string

Example:

[format]
item-indent = "indent"

wrap

How the formatter lays out line breaks inside a paragraph. It does not affect structure, only where soft line breaks fall.

ModeBehavior
reflowGreedy fill: pack words up to line-width, breaking only where the next word would overflow.
stablePreserve acceptable authored breaks and rebalance only text that no longer fits (keeps revision diffs small).
preserveLeave the authored line breaks untouched.
sentenceOne sentence per line. Line width is ignored—a long sentence stays on one line.
semanticSemantic line breaks: keep the author’s soft breaks and add a break after each sentence.

Both sentence and semantic split a paragraph at sentence boundaries, one sentence per line. Boundary detection is a small per-language rule engine over the words: a ., !, or ? ends a sentence unless the word is a known abbreviation (e.g., Fig., Dr., etc.) an ellipsis (..., ), or a contextual abbreviation whose following word signals that the sentence continues (U.S. Government stays together, U.S. However splits). The abbreviation profile is chosen by lang and extended by no-break-abbreviations.

In sentence mode, citation commands follow their grammatical role. Parenthetical and other postpositive forms, such as \parencite, \citep, and \autocite, stay with the preceding sentence—even when an authored line break has stranded one on the next line. Textual forms, such as \textcite and \citet, may begin the next sentence. Plain \cite is package- and style-dependent, so the formatter follows the source: it attaches on the same line but preserves an authored line break.

semantic additionally preserves the author’s own line breaks on top of the sentence breaks (the sembr convention). It does not detect clause boundaries itself—a break after a comma or and survives only where the author placed a newline. A run-on sentence on a single source line is still sentence-split.

stable also preserves authored line breaks, but treats them as preferred anchors rather than hard boundaries. It is aimed at keeping revision diffs small: a small prose edit perturbs the smallest possible region. Each prose run is solved as one global layout problem. Candidate layouts are compared lexicographically by total overflow, underflow below a soft target (line-width - 15), changed authored breaks, displacement from the nearest authored break, raggedness around that target, and line count. This makes the hard width non-negotiable before minimizing source churn, while a short final line remains unpenalized. Blank lines and command-only lines bound each independently optimized run, and code-like statement bodies retain ordinary greedy fill. (The soft target is not currently configurable.)

When omitted, every file kind reflows—.tex, .bib, .sty, .cls, .dtx, and .ins alike. A file’s extension is not a layout input.

That is safe because reflow is never the thing that decides whether content may move. The formatter declines to reflow anything it cannot lay out without changing meaning, in every wrap mode and regardless of what you configure: verbatim bodies and \verb, comments, .dtx documentation margins and docstrip guards (which must stay at column 0), and any documentation block whose rewrapping would push a % off column 0. Asking for wrap = "reflow" on a .dtx cannot corrupt it; asking for wrap = "preserve" on a .tex is a stylistic choice, not a safety one.

Code, in practice, has little to reflow: expl3 regions (\ExplSyntaxOn\ExplSyntaxOff) are laid out by their own rules whatever wrap says, and a source line consisting only of commands keeps its own line. So a package or class body formats much as it did before, and preserve remains available if you want authored breaks kept verbatim.

Default value: unset (reflow, for every file kind)

Type: "reflow" | "stable" | "sentence" | "semantic" | "preserve"

Example:

[format]
wrap = "stable"

math-wrap

How the formatter lays out line breaks inside display math: \[…\], $$…$$, and single-formula math environments such as equation. Alignment-grid environments (align, gather, matrices) and inline $…$ math are not affected.

ModeBehavior
autoDerive from the effective wrap: preserve keeps authored math breaks, every other mode breaks (amsmath).
preserveKeep the authored line breaks inside the body. Spacing within each line is still normalized.
single-lineNever insert breaks: the body stays on one line, overflowing line-width if too long (like inline math).
breakBreak a too-long body before its top-level relations and binary operators, aligning a relation chain (amsmath style).

Default value: "auto"

Type: "auto" | "preserve" | "single-line" | "break"

Example:

[format]
math-wrap = "preserve"

line-ending

How the line breaks in formatted output are spelled. The layout engine always decides where breaks go; this decides only the bytes they render as, and it applies to the whole document — including inside verbatim-style protected regions, which would otherwise keep their authored endings and leave the file mixed.

ModeBehavior
autoKeep the endings the file was written with: CRLF if its first line break is one, LF otherwise.
lfAlways \n.
crlfAlways \r\n.
nativeThe platform’s convention: \r\n on Windows, \n elsewhere.

The default is auto, so formatting never rewrites a repository’s line endings on its own — set lf (or add a .gitattributes rule) if you want them normalized.

Default value: "auto"

Type: "auto" | "lf" | "crlf" | "native"

Example:

[format]
line-ending = "lf"

lang

Document language as a BCP-47-style code (en, de, pt-BR, …), used by the sentence and semantic wrap modes to pick the sentence-boundary abbreviation profile. Built-in profiles cover English (default), Czech, German, Spanish, and French; the region subtag is folded away, and an unknown or unset language falls back to English. (Automatic detection from babel/polyglossia is not yet implemented.)

Default value: unset (English)

Type: string

Example:

[format]
lang = "de"

no-break-abbreviations

User-supplied no-break abbreviations for the sentence and semantic wrap modes, keyed by language code or the literal default bucket (applied to every document). An abbreviation listed here never ends a sentence, so no line break is inserted after it. Merged on top of the built-in per-language lists.

Default value: {}

Type: table of string arrays, keyed by language code or default

Example:

[format.no-break-abbreviations]
default = ["ibid."]         # applied to every document
de = ["bzw.", "Abb."]       # applied only when lang resolves to German

[lint]

Rule selection for badness lint, shared by the LaTeX and BibTeX rule sets. Most rules are on by default; each rule’s reference entry states whether it is default-enabled. An unknown rule id is reported at lint time, not rejected at config-parse time.

select

Explicit allowlist of rule ids. When set, only these rules run.

Default value: unset (all default-enabled rules run)

Type: array of strings

Example:

[lint]
select = ["deprecated-command", "dollar-display-math"]

To enable the opt-in dash check:

[lint]
select = ["dash-length"]

ignore

Rule ids to disable, applied on top of either select or the default rule set.

Default value: []

Type: array of strings

Example:

[lint]
ignore = ["missing-nonbreaking-space"]

[build]

Where the TeX compiler leaves its artifacts, and which file it was run on. Read by the language server only — it pulls resolved label and section numbers from the .aux files for hover and document symbols, and locates the compiled PDF for forward search. Never read by the formatter or linter.

aux-dir

Directory holding the build’s .aux files (latexmk’s -auxdir/-outdir), resolved relative to the root document’s directory when not absolute. When unset, each document’s .aux is expected next to it, as in plain latex/pdflatex runs.

Default value: unset (sibling .aux files)

Type: path

Example:

[build]
aux-dir = "out"

pdf-dir

Directory holding the build’s PDF output (latexmk’s -outdir), resolved relative to the root document’s directory when not absolute. When unset, the PDF is expected next to the root document.

Default value: unset (the root document’s own directory)

Type: path

Example:

[build]
pdf-dir = "out"

pdf-filename

The compiled PDF’s file name, when the build does not name it after the root document (latexmk’s -jobname). A bare file name, never a path — use pdf-dir for the directory — and .pdf is appended when it carries no extension, so "thesis" and "thesis.pdf" mean the same thing.

Default value: unset (<root document stem>.pdf)

Type: string

Example:

[build]
pdf-filename = "thesis.pdf"

root

The project’s root document — the file the compiler was run on — resolved relative to this badness.toml’s directory when not absolute.

Normally the root is found by scanning the project for a file carrying \documentclass or \begin{document}, and you do not need this key. But that scan only sees files the server has already loaded, and it loads them one directory at a time: editing chapters/ch1.tex in a project rooted at ../main.tex never loads main.tex, so the scan finds no root at all and forward search resolves the wrong PDF. Set root for that layout.

Default value: unset (scan the project for a document root)

Type: path

Example:

[build]
root = "main.tex"

[commands]

Declares project commands whose first braced argument contains label or citation keys. This covers wrappers that Badness cannot recognize without macro expansion, which remains deliberately out of scope.

Entries are keyed by the command name without its leading backslash:

# A comma-separated list of label keys.
[commands.eqrefs]
like = "cref"

# A comma-separated list of bibliography keys.
[commands.projectcite]
like = "parencite"

The like target must be a curated reference or citation command. It determines the key behavior: ref/eqref accept one label, cref and its list-valued siblings split on commas, citation commands split on commas, and nocite preserves the special * wildcard.

Command declarations affect linting, label/citation navigation, rename, and key completion. They do not expand the macro, declare its arity, change argument attachment, or lend formatter layout. Use the command whose observable key behavior matches the wrapper: an eqrefs command that accepts several labels is like = "cref", even if its implementation calls \eqref once per key.

Anything that would silently do nothing is a configuration error: an empty entry, an invalid control-word name, an unknown or non-ref/cite like target, or an attempt to reclassify a curated built-in command.

Command like

The curated reference or citation command whose key behavior this project command copies.

Type: string

Example:

[commands.eqrefs]
like = "cref"

[environments]

Declares environments Badness cannot recognize from the file alone: one that behaves like a built-in but has no built-in counterpart, one whose body is verbatim, and one reached through command spellings rather than \begin/\end. This is the only section that changes how your files are parsed, so it is read by format, lint, and the language server alike; editing it makes the server reparse the project.

Entries are keyed by the environment’s own name, whether or not Badness already knows it:

# \begin{myenv} … \end{myenv}, with no built-in counterpart
[environments.myenv]
like = "align"

# extra delimiter spellings for an environment Badness already knows
[environments.eqnarray]
begin = ['\bea']
end = ['\eea']

# one side alone: `\bsplit` expands to `\begin{split}`, so a written-out
# `\end{split}` closes it — there is no closing command to declare
[environments.split]
begin = ['\bsplit']

# both at once: an environment reached only through commands
[environments.mytheorem]
like = "theorem"
begin = ['\startmyenv']
end = ['\endmyenv']

Write control words as TOML literal strings (single quotes) so the backslash needs no escaping: '\bea', not "\\bea". Both spellings are accepted, and so is a name with no backslash at all — a control word can never contain one, so there is nothing to disambiguate.

A declaration names a spelling, never a pairing. Every structural rule still applies, so a declared \bea whose \eea is unreachable — stranded inside a brace group, or simply missing — stays an ordinary command, exactly as it would without the declaration. A wrong declaration therefore does nothing to your document; it cannot corrupt it.

What a declaration cannot do is invent behavior. It only ever points at an environment Badness already curates, so there is no way to spell out “this one is math, takes two arguments, and has a verbatim body” key by key. If nothing built in resembles yours, that is worth an issue rather than a workaround.

Anything a declaration cannot satisfy is an error at config load, reported against the key you wrote, rather than a block that parses and quietly does nothing:

  • an entry with no keys under it, which would declare nothing at all
  • like naming an environment Badness does not know
  • delimiter spellings for a verbatim environment (the closing command is never seen — the verbatim body has already swallowed it)
  • delimiter spellings for an environment that takes arguments (a bare command carries none)
  • delimiter spellings for an environment with no like and no built-in of that name, so its behavior is unknown
  • one spelling claimed by two entries, or listed twice by one
  • a spelling that is the delimiter itself ('\end{split}') rather than a command standing in for one — the written-out delimiter already pairs with a declared spelling, so the key can just be removed
  • a spelling that could never be a single control word ('\b ea', '\bea2')
  • a spelling that is already a LaTeX command Badness knows ('\emph'), which would change what that command means throughout the project

like

The built-in environment whose behavior this one copies: whether its body is math, whether it aligns on &, whether it is verbatim, and every such property at once. This is also how you name a verbatim environment defined by machinery no scan can follow — like = "lstlisting" protects its body from reflowing and from lint findings.

The target is looked up among the environments Badness curates by hand; a misspelled one is an error rather than a silent no-op.

Default value: unset

Type: string

Example:

[environments.mycode]
like = "lstlisting"

begin

Command spellings that stand in for this environment’s \begin{…}. Any of them opens it, and any spelling in end closes it — pairing is by side, not by position, so the two lists need not be the same length.

The written-out \end{…} closes it too, which is why end is optional. A command defined as \def\bsplit{\begin{split}} expands to \begin{split}, so \bsplit … \end{split} is a perfectly ordinary environment and there may be no closing command to name at all.

Use this when the definition is somewhere Badness cannot see: a sibling .sty, or one built by machinery no scan follows. A definition written with a plain \newcommand or \def in the same file — \newcommand{\bea}{\begin{eqnarray}}, or \def\bsplit{\begin{split}} on its own — is already recognized without any configuration.

A spelling must be a command of your own. Naming one Badness already knows ('\emph', '\section') is an error rather than a redefinition: the declaration would apply everywhere that command appears, which is never what a delimiter declaration means.

Default value: []

Type: array of strings (control words)

Example:

[environments.eqnarray]
begin = ['\bea', '\beqa']
end = ['\eea']

end

Command spellings that stand in for this environment’s \end{…}, the mirror of begin in every respect — including that it stands alone. A command defined as \def\eeq{\end{equation}} closes a written-out \begin{equation}, so an entry may name a closing spelling without naming an opening one.

Default value: []

Type: array of strings (control words)

Example:

[environments.eqnarray]
begin = ['\bea']
end = ['\eea']

Note: TEXMF-tree discovery (the former [texmf] section) is configured through your editor’s LSP settings, not badness.toml. Where a TeX installation lives is a fact about the machine, not the project, so it does not belong in a file shared across contributors. See Editor Setup.