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shahules

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My team works on automatic environment generation for RL post-training. One of our projects is using coding agents to build web clones for BUAs/CUAs.

We tested Gemini, Claude Code, GLM, and Codex using our harness on their abilities to recreate a Slack workspace and benchmarked their performance.

Saw a variety of results:

- *Gemini 3 Pro:* Achieved the highest visual score (0.91 SSIM) but lacked interactive functionality. - *Claude Opus 4.6:* Developed the most complete application, balancing full interactivity with consistent self-correction. - *GLM-5:* Produced the best code architecture but reached a plateau in visual improvement. - *GPT-5.3 Codex:* Initialized quickly but entered a five-hour "scaling spiral" that failed to yield further progress.

Next, we’re planning:

- More web apps for cloning and benchmarking across the models - More functionality (the trajectory didn’t include full Slack features) - Better scoring for functionality (easier to catch Gemini’s mistake)

Repo: https://github.com/vibrantlabsai/cloning-bench

Blog post: https://vibrantlabs.com/blog/pa-bench

Most current web agent benchmarks focus on single-tab tasks (e.g., 'go to Gmail and star this email'). We found that frontier models that score highly on those tasks (like in WebArena) often fall apart when they have to coordinate context across 2+ applications. We built a simulated environment with scenarios and deterministic verifiers to see why.

It's an interesting article and I agree with some points you brought up here. But here are some of them to which I don't agree to

1. Evals are used throughout the article in the sense of LLM benchmarking, but this is not the point. One could effectively evaluate any AI system by building custom evals.

2. The purpose of evals is to help devs systematically improve their AI systems (at least how we look at it) not any of the ones listed in your article. It's not a one-time thing, it's a practice like the scientific method.

Deepeval also uses Ragas underneath. They initially took a different approach by allowing uses to formulate test cases but we were focusing on RAGs only and creating metrics and features like synthetic test data generation for it. Now that we are doing good in the RAG category, we also want to expand to solve the greater challenge.

1) Horizondal expansion and support are core to every framework/library. This won't make us a competitor to LC, we actually use langchain-core to support many of these like supporting different LLMs. 2) We operate in a layer underneath the stack of evals and testing because we want to solve the problem from the ground up rather than building a fancy tracing tool, which comes later in the stack.

Thanks for your feedback. We have tested Ragas on alternatives like Claude, Mixtral, Gemini, etc.

Although we support all LLMs supported by Langchain, sadly many of the OSS models out of the box aren't capable of generating JSON-type output which is important for us to ensure reproducibility.

Thank you for asking this question.

To answer this question, I will explain two directions of Ragas.

The first one is the horizontal expansion of the library which involves features like

- Giving you the ability to use any LLMs instantly without any hassle

- Asynchronous evaluations, integrations with tracing tools, etc

- Automatic support to adapt metrics to any language

The second is vertical expansion or adding more core features like metrics to Ragas which includes.

- Synthetic test data generation: this is something that is heavily loved by our community so we are continuously improving the quality of it. https://docs.ragas.io/en/stable/concepts/testset_generation....

Now, as we expand in both directions we aim to solve the problem of how to evaluate and test compound systems. Now, to solve this we will be innovating and working on features like feedback utilization, automatically synthesizing assertions, etc to solve this hard problem.

I hope I was able to answer your question. Would love to discuss more.

This guy doesn't have any idea what he is talking about. He consistently posts such bullshit on twitter. Mostly copy paste with added spice mix.