Tools: I loaded 50 rules into Cursor and it followed every single one

The setup ## What actually happened ## You don't need to keep it under 10 ## Why I think people are still saying to keep it low ## Sidenote I keep seeing people online worry about how many .cursorrules they can have before Cursor starts ignoring them. "Don't use too many rules," "keep it under 10," that kind of thing. But where was this coming from? Was there any truth to it? So I tested it. I made 50 rules, loaded them all at once, and ran the same refactoring task 18 times across different rule counts. I created rules for things that are easy to verify. always-semicolons, no-console-log, interface-prefix, early-return, stuff where you look at the output and can immediately tell if it was followed. I started at 1 rule and scaled up: 1, 5, 10, 20, 30, 50. Every rule had alwaysApply: true and proper frontmatter. The same task, 3 runs at each level. I expected it to start falling off somewhere around 15-20 rules; that's what the online advice implies. Context windows have limits, models forget stuff, right? 100% compliance across all 18 runs. At every level. Including 50 rules at once(!) I honestly thought I'd messed up the test. I checked the output files manually, rule by rule, and every single one was addressed. Some rules got marked "N/A" when they didn't apply to the test file (like cors-explicit when there's no API endpoint), but the model explicitly acknowledged them instead of silently skipping them. At least for the current version of Cursor with Auto mode. I can't speak for older versions or other tools, but right now, 50 rules with alwaysApply: true and proper frontmatter all fire correctly. The people warning about "too many rules" are probably running into a different problem. Bad frontmatter, missing alwaysApply, vague rules that the model interprets differently than intended. Those are real issues that look like "the model forgot my rule" but are actually structural failures. I've seen this pattern a lot. Someone has 15 rules, 3 of them aren't firing, and they assume it's a quantity problem when it's actually a formatting problem. The rule count isn't the bottleneck. The rule quality is. I didn't go above 50. There's probably a ceiling somewhere, I just don't know where it is. If you've got 100+ rules loaded I'd be genuinely curious whether compliance holds. I also only tested with one task type (refactoring). Different tasks might interact with rules differently. If you want experiment results when I run them, I have a newsletter that goes out when I have findings. No schedule, no fluff. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse