Which issues does it check for?

It checks for trailing whitespace, hard tabs, multiple consecutive blank lines, bare URLs, heading levels that jump by more than one, and code fences that are opened but never closed.

What does auto-fix change?

Auto-fix only touches whitespace-level issues that are safe to rewrite automatically — trailing spaces, hard tabs, and runs of blank lines. Structural issues like heading jumps and unclosed fences are reported but left for you to fix.

Does it follow the real markdownlint rules?

It mirrors several of the most common markdownlint rules in spirit so the output is familiar, but it is a lightweight in-browser checker, not the full markdownlint engine with every rule and option.

Is my content uploaded anywhere?

No. All linting and fixing happens in your browser with no network requests, so you can paste private documents safely.

Why lint LLM markdown specifically?

LLMs frequently emit trailing spaces, bare links, and heading jumps that look fine in a chat window but break or look messy when rendered in a real site or doc. Linting catches them before they ship.

LLM Markdown Linter — Gera Tools

LLM markdown linter

LLMs are fluent markdown writers, but they leave small messes: trailing spaces, bare URLs that should be links, heading levels that jump from H2 to H4, and code fences they forget to close. Those render badly or break entirely once the text leaves the chat box. This linter checks for the most common offenders and auto-fixes the safe ones, all in your browser.

How it works

The tool scans your markdown line by line. It flags trailing whitespace, hard tabs, runs of three or more blank lines, and bare URLs not wrapped as links. It tracks heading levels to catch jumps greater than one (an H2 followed directly by an H4), and it counts triple-backtick fences to warn when one is opened but never closed. Each finding shows a line number and a plain-language reason. Auto-fix rewrites only the whitespace issues that are always safe to change.

Tips and notes

Fix structure by hand. Heading jumps and unclosed fences are reported, not auto-fixed, because the right repair depends on intent.
Bare URLs are a frequent LLM tell. Wrap them as [text](url) so they render as proper links and read cleanly.
Run it before committing docs. Catching whitespace and fence issues here keeps your rendered docs and READMEs tidy.
Re-lint after auto-fix. A clean second pass confirms only the structural items remain for you to address.