Trying to make a media player, media server, all by using ffmpeg and a pre-built media streaming engine as it's core. Python and SQLite. About a week's worth of effort every time until it begins to go too far off the rails to be reliable to continue to develop with. It never did get the ffmpeg commands right, I had to go back to crafting those by hand, it never did get the streaming engine to play in the browser's video player in the supported hls and dash formats. Asked it to build a file and file metadata caching layer and then had to continue to re-prompt it to poll the caching layers before trying to get values from the database. Never even got to the library, metadata, or library image functionality. Had to ask it to create the rbac permissions model I wanted despite it being very junior-level common sense (super-admin, user-admin, metadata admin, image admin).
Not exactly world-class software.
I recently built something in the same universe - using ffmpeg to receive streams from obs to capture audio and video - don't want to get into details beyond except to say it involved a fairly involved pipeline of ray actors and a significant admin interface with nicegui. I had no problem doing this with claude. You need to give it access to look up how do things, like context7. If you are doing something very specific, you need to have a session that does research to build a skill so it doesn't need to redo that research every time. And yes, you do need to tell it the architecture and be fairly detailed with something like how you want rbac.
Using these tools takes quite a bit of effort but even after doing all those steps to use the tool well, I still got this project done in a few days when it otherwise would have taken me 1-2 months and likely simply would never happened at all.
I think you have every right to doubt those telling us that they run 5 agents to generate a new SAAS-product while they are sipping latté in a bar. To work like that I believe you'll have to let go of really digging into the code, which in my experience is needed if want good quality.
Yet I think coding agents can be quite a useful help for some of the trivial, but time consuming chores.
For instance I find them quite good at writing tests. I still have to tweak the tests and make sure that they do as they say, but overall the process is faster IMO.
They are also quite good at brute-forcing some issue with a certain configuration in a dark corner of your android manifest. Just know that they WILL find a solution even if there is none, so keep them on a leash!
Today I used Claude for bringing a project I abandoned 5 years ago up to speed. It's still at work in progress, but the task seemed insurmountable (in my limited spare time) without AI, now it feels like I'm half-way there in 2-3 hours.