There is almost nothing new in computer programming. 99.999% of any code most of us on this forum write will be repeating patterns that have been written thousands of times before.

Tell a coding agent what your new thing needs to do, give it the absolute constraints, max response times, max failover times, and so on, tell it which technologies it has access to or could use, and then tell it to spend a lot of time going over and over the design, coming up with an initial X number of designs (I use 5), and then it must self criticise each one of them and weigh them up, narrow down to three, before finally presenting those three options to the user.

Now you read the options, understand them, realise that the AI has either converged on something very sensible, or it has missed something, so you tell it what it missed and iterate. Or it nailed something good, you pick the option you prefer, and tell it to come up with a more fleshed out high level design, describing the flow and behaviour deeply (NO CODE REFERENCES!). Then once you're happy, tell it to use that and write a comprehensive coding plan. Tell it specifically what coding patterns you prefer (you should have these in your AGENTS.md file already), what patterns to avoid (single threaded? multi-threaded? Avoid gc? How you typically deal with error conditions, etc etc).

Then have it start iteratively working on the coding plan, and it *MUST* have a strong feedback loop. If there is no feedback loop initially, I tell it to build one. It must be able to write very fluent integration tests (not just unit tests). It must be able to run the app and read the logs.

Do all this and I bet you get a better result that 80% of developers out there. Coding agents are extremely good when used well.