The Five Checks

markdown-checker registers five checks, selected with -f/--func. Each check consumes either the paths or the URLs extracted from a file (see How Link Detection Works), never both.

check_broken_paths

Flags

Relative or root-relative links whose target file does not exist on disk, e.g. [guide](./missing.md) when missing.md isn’t there.

Ignores

Web URLs, mailto:-style links, and bare #fragment links. Query strings/anchors on a path (docs/usage.md#section) are stripped before checking existence.

Options that affect it

SRC/--dir, --extensions, --skip-files (which files are scanned in the first place). Domain/URL skip options do not apply - this check never makes network requests.

Sample finding

File 'docs/index.md', line 5
./missing.md is broken.

check_broken_urls

Flags

Web URLs that don’t return a 2xx HTTP response after retries.

Ignores

Hosts in --skip-domains or the built-in list of hosts known to block automated requests; URLs matching --skip-urls-containing.

Options that affect it

--skip-domains, --skip-urls-containing, --timeout, --retries, --retry-on-429, --fallback-retry-delay, --max-workers, --per-host-delay.

Severity

Reports a mix of error-level (broken) and warning-level (rate_limited, unverifiable, transient_error) issues - see Exit Codes and Issue Severity for the full status table.

Sample finding

File 'docs/index.md', line 8
https://example.com/gone is broken.

check_urls_locale

Flags

URLs whose path contains a locale segment, e.g. /en-us/ in https://example.com/en-us/docs. A “locale segment” is a language-country pair matching xx-xx (case-insensitive).

Ignores

www.nvidia.com (built in - its docs always include a locale segment), plus any host in --skip-domains or URL in --skip-urls-containing.

Options that affect it

--skip-domains, --skip-urls-containing.

Sample finding

File 'docs/index.md', line 8
https://example.com/en-us/docs has locale.

check_urls_tracking

Flags

URLs on a configured tracking domain that are missing a wt.mc_id query parameter.

Ignores

URLs on hosts not listed in --tracking-domains (the check does nothing for them), plus any host in --skip-domains or URL in --skip-urls-containing.

Default tracking domains

github.com, microsoft.com, visualstudio.com, aka.ms, azure.com.

Options that affect it

--tracking-domains, --skip-domains, --skip-urls-containing.

Sample finding

File 'docs/index.md', line 8
https://learn.microsoft.com/azure/ is missing tracking id.

check_paths_tracking

Flags

Every relative path link missing a wt.mc_id query parameter. Unlike check_urls_tracking, there is no domain filter - all paths are checked.

Options that affect it

SRC/--dir, --extensions, --skip-files only.

Sample finding

File 'docs/index.md', line 5
./usage.md is missing tracking id.