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Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by podoman on Monday November 02, 2026 @12:42PM (#50340540)
> Mo is a custom agent harness for catching bugs that builds on the past 3 years of Momentic and millions of test traces from complex, real-world applications. Mo is built for recall: it finds the most real bugs, though Codex is a bit more precise at 86% vs 84%. The tradeoff is cost: Mo costs $2.67 per bug vs $0.80 for Codex, less than Claude Code and Devin.

is this good? so Mo costs more money per bug? I'm confused.

Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by momentichenry on Monday November 02, 2026 @01:00PM (#50340823)
Hey! I'm Henry, one of the engineers working on Mo. You're looking at the right numbers, but the takeaway is slightly different from ours.

The main thing we're trying to show is that Mo finds over 3x as many correct bugs in the same amount of time as the next-best QA agent. This is the main thing we optimize for since the worst thing you can do in QA is miss a real bug and ship broken code to prod. Currently, the tradeoff you make for that better recall is higher cost. I would say the precision is more or less comparable, but marginally lower.

Obviously we'd love to be beating every other agent on all of these numbers, and we're actively working on it, but for now this is an honest and transparent look at how the tool is doing.

Feel free to take a look at the full writeup for more detail!

Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by mlcruz on Monday November 02, 2026 @01:32PM (#50341346)
I feel like your writeup could be a little stronger if you made it clear how important is hitting those recall targets.

I also do believe search quality is recall dominated, but the link between the metrics and results are not as clear as they could have been. I think you have a stronger sell here than it looks at first glance.

Congratulations to the team tho! Those are very nice results

Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by momentichenry on Monday November 02, 2026 @01:41PM (#50341490)
Thanks! That's fair feedback. We'll update the writeup to make this clearer. We're also hoping to release a v2 benchmark soon with more fixtures and hopefully an even more optimized Mo.
Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by StilesCrisis on Monday November 02, 2026 @10:26PM (#50347665)
> the worst thing you can do in QA is miss a real bug and ship broken code to prod

Maybe it varies by domain but I'm quite used to codebases where "fix every discovered bug" is basically infeasible; finding 1000 miniscule bugs isn't helpful. Finding _serious_ bugs is the goal.

Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by Smoofer on Monday November 02, 2026 @12:48PM (#50340633)
Right? Is the takeaway from that not just that Codex is better for cheaper?
Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by luckydata on Monday November 02, 2026 @12:47PM (#50340630)
it's right there in the writeup, it costs more but finds more bugs.
Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by bigmadshoe on Monday November 02, 2026 @10:40PM (#50347761)
This sentence is so badly written. What they were trying to say is that their product has much higher recall, slightly lower precision, and costs somewhere between Codex and Claude Code. You can see this by looking at the chart they included below, but I have no idea how this post made it to HN without someone noticing how confusing it is.
Re:Launch HN: Momentic (YC W24) – Agents that catch bugs by ... by neya on Monday November 02, 2026 @11:16PM (#50347995)
What a great marketing campaign for Codex, I tried reading a couple of times and I concluded I should renew my codex subscription.