Grink is a tool to find and check web links in text files (for example, Markdown source files). It “greps links”, if you will.
cargo install grink
Grink reads all the files you specify, extracts anything that looks like a URL, and checks if it returns an OK status, reporting the error otherwise.
grink book/*.md
[ERROR] (HTTP status client error (404 Not Found) for url (https://example.com/bogus)) https://example.com/bogus - referrer: book/chapter1.md
Links: 8 (7 OK, 1 errors, 0 warnings)