alt Hacker NewsOpus 4.5 ate through my Copilot quota last month, and it's already halfway through it for this month. I've used it a lot, for really complex code.
And my conclusion is: it's still not as smart as a good human programmer. It frequently got stuck, went down wrong paths, ignored what I told it to do to do something wrong, or even repeat a previous mistake I had to correct.
Yet in other ways, it's unbelievably good. I can give it a directory full of code to analyze, and it can tell me it's an implementation of Kozo Sugiyama's dagre graph layout algorithm, and immediately identify the file with the error. That's unbelievably impressive. Unfortunately it can't fix the error. The error was one of the many errors it made during previous sessions.
So my verdict is that it's great for code analysis, and it's fantastic for injecting some book knowledge on complex topics into your programming, but it can't tackle those complex problems by itself.
Yesterday and today I was upgrading a bunch of unit tests because of a dependency upgrade, and while it was occasionally very helpful, it also regularly got stuck. I got a lot more done than usual in the same time, but I do wonder if it wasn't too much. Wasn't there an easier way to do this? I didn't look for it, because every step of the way, Opus's solution seemed obvious and easy, and I had no idea how deep a pit it was getting me into. I should have been more critical of the direction it was pointing to.
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People are completely missing the points about agentic development. The model is obviously a huge factor in the quality of the output, but the real magic lies in how the tools are managing and injecting context in to them, as well as the tooling. I switched from Copilot to Cursor at the end of 2025, and it was absolute night and day in terms of how the agents behaved.
yes just using AI for code analysis is way under appreciated I think. Even the most sceptical people on using it for coding should try it out as a tool for Q&A style code interrogation as well as generating documentation. I would say it zero-shots documentation generation better than most human efforts would to the point it begs the question of whether it's worth having the documentation in the first place. Obviously it can make mistakes but I would say they are below the threshold of human mistakes from what I've seen.
If it can consistently verify that the error persists after fix--you can run (ok maybe you can't budget wise but theoretically) 10000 parallel instances of fixer agents then verify afterwards (this is in line with how the imo/ioi models work according to rumors)
> Opus 4.5 ate theough my Copilot quota last month
Sure, Copilot charges 3x tokens for using Opus 4.5, but, how were you still able to use up half the allocated tokens not even one week into January?
I thought using up 50% was mad for me (inline completions + opencode), that's even worse
It acts differently when using it through a third party tool
Try it again using Claude Code and a subscription to Claude. It can run as a chat window in VS Code and Cursor too.
>So my verdict is that it's great for code analysis, and it's fantastic for injecting some book knowledge on complex topics into your programming, but it can't tackle those complex problems by itself.
I don't think you've seen the full potential. I'm currently #1 on 5 different very complex computer engineering problems, and I can't even write a "hello world" in rust or cpp. You no longer need to know how to write code, you just need to understand the task at a high level and nudge the agents in the right direction. The game has changed.
- https://highload.fun/tasks/3/leaderboard
- https://highload.fun/tasks/12/leaderboard
- https://highload.fun/tasks/15/leaderboard
Copilot and many coding agents truncates the context window and uses dynamic summarization to keep costs low for them. That's how they are able to provide flat fee plans.
You can see some of the context limits here:
https://models.dev/
If you want the full capability, use the API and use something like opencode. You will find that a single PR can easily rack up 3 digits of consumption costs.