slop-grader is a rule-based CLI tool that evaluates documents against custom rulesets and produces document scores and line-by-line flags to guide auto-fixing with an AI agent. Use it to catch AI filler in launch copy, to strip buzzwords from landing pages, score narrative flow in launch emails. Flagged lines let agents draft sharper copy. The tool flags outputs prompts so agents can draft fixes.
I built slop-grader, an open-source tool that checks any text document against rules like English grammar, German grammar, and AI filler detection.
You can also write custom rules for specific workflows using plain language: SEO checks, legal clauses, or tone of address (like keeping German "Du" vs. "Sie" consistent). Rules are questions evaluated line by line ("Does this line make a promise that requires a legal disclaimer?") or across the entire document ("Does the opening earn the reader's next 30 seconds?"). Once you build a curated ruleset for your use case, it can be a very powerful tool.
It runs on Jev (https://typesafe.ai), which is a new AI model, different from a LLM (a so called System One model) specialized in answering structured questions. Checking a document takes seconds and costs less than a cent.
The tool outputs a list of flagged lines and instructions that you can paste directly into an AI agent to fix the document.
To run it, you need Node.js installed on your machine and an account with either TypeSafe or OpenRouter.
Be aware that text is evaluated on an external AI server.
the Du vs Sie consistency example is a good one because it shows this isn't just an "AI filler" detector, it's closer to a linter for anything you can phrase as a yes/no question about a line. we ship voice agent scripts and the equivalent problem for us is formality drift across a long call flow - a script written over multiple sessions slowly shifts tone without anyone noticing until a user points it out. one question on the output format: when a rule fires on a line, does slop-grader give you just the line number and the rule text, or does it also explain why it thinks the rule was violated? that's usually the gap between "useful lint" and "lint you end up ignoring"
Can the output be used directly in an AI coding or writing agent workflow or is it mainly meant to be reviewed manually?
It could be useful to have a strictness setting for the ruleset so users can choose between a quick cleanup and a much deeper review.
How do you handle words that might be considered buzzwords in one industry but are completely normal in another?
The line by line flags are a useful touch. It makes it much easier to see exactly what needs fixing instead of rewriting the whole document.
About slop-grader on Product Hunt
“Jev-AI CLI tool that evaluates text against custom rulesets”
slop-grader launched on Product Hunt on September 21st, 2026 and earned 88 upvotes and 10 comments, placing #15 on the daily leaderboard. slop-grader is a rule-based CLI tool that evaluates documents against custom rulesets and produces document scores and line-by-line flags to guide auto-fixing with an AI agent. Use it to catch AI filler in launch copy, to strip buzzwords from landing pages, score narrative flow in launch emails. Flagged lines let agents draft sharper copy. The tool flags outputs prompts so agents can draft fixes.
slop-grader was featured in Writing (59.4k followers), Advertising (29.9k followers), Artificial Intelligence (479.1k followers) and GitHub (41.4k followers) on Product Hunt. Together, these topics include over 170k products, making this a competitive space to launch in.
Who hunted slop-grader?
slop-grader was hunted by Lukas. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.
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