Sujay Jayakar discusses findings from the Fullstack-Bench benchmark evaluating AI coding agents across different backend paradigms.
Assertion Supported
Cursor Composer solves Convex benchmarks but fails on alternative backends
“We did notice that I mean, with convex, it pretty much autonomously just solves the first two tasks. It has a few round trips on like some errors that are only show up and playing with the front end. And then it's able to complete this files task and kind of g…”
Assertion Not checkable as stated
Claude 3.7 performed worse than Claude 3.5 on Convex evals
“For example, we just tried clod three seven and it performs worse than clod three five on convex evals with the same prompting.”
Assertion Not checkable as stated
AI hallucinates Convex code due to API similarities with Firebase
“I mean, I think one thing that's kind of interesting given these, you know, models inherent internal structure is that we noticed that a lot of hallucinations come from parts of our API that are like very close to Firebase, but not exactly Firebase.”
Assertion Supported
Claude 3.5 in Cursor autonomously codes for 10 plus minutes
“When it has the right feedback in cursor composer, and this was even on cloud three, five, it can just autonomously code for a 10 plus minutes and it can fix its own bugs. It can get to the point where it's like pretty much a fully working app with just an ini…”
Assertion Not checkable as stated
OpenAI's o3 outperforms GPT-4o on Convex evals by a small margin
“You know, oh, three does do better than four. Oh, I mean, we use brain trust for tracking all this quantitatively, but I can't remember off the top of my head, but it's not like a slam dunk.”
Insight
End-to-end type safety and tight feedback loops improve AI agent performance
“It's like, you know, having just really tight feedback loops and having strong guardrails, like in convex, that's like end to end type safety, but that's like, you know, could take it in many, many different forms, right? Like making it so code is very cheap a…”