Ask HN: In December 2025 what agentic tool should I try?

I have a recipe web application I built a while back with Svelte. Very fun, but I've got too much else to do and I don't have time to implement features. I am a daily-ish user of chat bots, find them mostly not very useful, but the hype is strong and this seems like a good playground.

My goal is some agent programmer that takes a Gitlab issue (e.g. "implement a timer in the UI") and makes a pull request implementing it. The only other constraint is I want to control spend: I would rather wait for it to implement stuff than spend more than X$ per week etc.

I could imagine building something like this which makes me think it's already built. Have any of you setup something similar? What did you use? What were the pros and cons?