master-css lint

Run machine-readable Master CSS diagnostics for source files.

Invocation and options

master-css lint [options] [source paths...]

Run from the project root. Omit source paths for ordinary source discovery, or quote a path/glob argument to scope the scan. Explicit paths replace the default file selection; they are not additional includes. This command runs native class diagnostics; it does not load the project’s ESLint configuration.

source paths

path[]Optional

The glob pattern paths to lint sources

--stdin

flagOptional

Read source content from stdin.

--stdin-filepath <path>

valueOptional

File path used to infer the stdin source language.

--fix

flagOptional

Apply safe class-list fixes to files.

--fix-dry-run

flagOptional

Return fix proposals without writing files.

--fix-directives

flagOptional

Allow structural directive fixes when --fix writes files.

--format <format>

valueOptional

Diagnostic output format: json or stylish. (default: "json")

--rules <rules>

valueOptional

Comma-separated lint rules, "recommended", or "all".

--exit-code <mode>

valueOptional

Exit code behavior: diagnostics or never. (default: "diagnostics")

--max-warnings <number>

valueOptional

Exit with a non-zero status if warnings exceed this count.

-h, --help

flagOptional

display help for command

Usage: master-css lint [options] [source paths...]Run machine-readable Master CSS diagnostics for source files.Arguments:  source paths             The glob pattern paths to lint sourcesOptions:  --stdin                  Read source content from stdin.  --stdin-filepath <path>  File path used to infer the stdin source language.  --fix                    Apply safe class-list fixes to files.  --fix-dry-run            Return fix proposals without writing files.  --fix-directives         Allow structural directive fixes when --fix writes                           files.  --format <format>        Diagnostic output format: json or stylish. (default:                           "json")  --rules <rules>          Comma-separated lint rules, "recommended", or "all".  --exit-code <mode>       Exit code behavior: diagnostics or never. (default:                           "diagnostics")  --max-warnings <number>  Exit with a non-zero status if warnings exceed this                           count.  -h, --help               display help for command

Effects and lifecycle

Without --fix, source files remain unchanged. --fix applies supported class-list fixes, then reports remaining diagnostics. --fix-dry-run prevents writes even when --fix is also present. Add --fix-directives only when structural directive rewrites are intended.

--stdin reads a buffer instead of project files; --stdin-filepath supplies its language context and defaults to stdin.html. Stdin buffers are not written back to disk, even with --fix.

Output and errors

The default --format json writes a versioned report to stdout. --format stylish writes human-readable output to stderr. With the default --exit-code diagnostics, errors produce a nonzero status; warnings do so when their count exceeds --max-warnings. --exit-code never suppresses diagnostic-based failure, so read the report before treating the command as a passing check. Argument and process failures can still fail.

The JSON report contains cwd, manifest, files, and summary. Clean files are omitted from files; diagnostic records may contain fix proposals. This report is not a complete before/after file diff. Use the MCP preview workflow when you need full proposed file contents before applying them.

Example

Run from the project root after installing the CLI:

Inspect class-order proposals in one existing source file:

master-css lint "src/button.html" \  --rules sort-classes \  --fix-dry-run

Apply those class-order fixes after reviewing the proposals:

master-css lint "src/button.html" \  --rules sort-classes \  --fix

Inspect a source buffer on stdin without modifying its virtual file:

master-css lint --stdin \  --stdin-filepath src/button.html \  --rules sort-classes <<'HTML'<button class="p-md flex">  Save</button>HTML

See the CLI guide for setup.