Large language models have always felt a bit abstract to me, so to get a more concrete sense of what they can actually do, I recently deployed GPT-3.5 alongside Alibaba’s open-source Qwen-7B locally, and tried applying both to real scenarios from my day job.
A few test scenarios#
1. Un-tuned open models sitting exams from different professional fields
I picked a few exams from our internal training platform that don’t require any prep beforehand, and used a Chrome AI extension I built myself to have both GPT-3.5 and the open-source Qwen model take them — with no fine-tuning at all. A few things stood out from the results:
- The more specialised the networking knowledge, the better the models scored.
- On national or industry-standard rules and procedures (procurement guidelines, for example), they also scored solidly above average.
- On exams about our own internal, highly customised products, the models fell well short — those questions are simply too specific.
Takeaway: an off-the-shelf open model performs roughly like a competent new graduate (arguably a bit better). Some targeted “training” (i.e. fine-tuning) is enough to make it genuinely useful for certain roles.
2. The “overconfident nonsense” problem
Careful prompt engineering can mostly stop a model from improvising and keep it answering only from what it actually knows.
3. How hard is it to stand up a local model?
The bar is low. Open models like Qwen-7B can be deployed with a single command. There’s no real technical difficulty in the deployment itself — what actually needs work is efficiency: GPU driver loading, system-level tuning, that kind of thing.
Some thoughts#
A rough three-layer way to think about LLM architecture:
- Foundation layer — both domestic and overseas open models are already good enough for direct use in a lot of professional contexts. What’s needed here isn’t teaching a model from scratch, it’s the equivalent of upskilling a new graduate. This layer should lean toward optimisation over construction:
- Efficiency: responding quickly to front-end requests and squeezing every bit of GPU capacity out of the hardware.
- Fine-tuning: loading tuning data from different formats into whichever base model sits underneath.
- Agent layer — the underlying model capability is open to everyone (a level playing field), and the front-end requirements are broadly the same across companies. The real differentiation in AI products comes from how well you build the “requirement ↔ model” middleman.
- Front-end UI — presenting the AI capability to the user. This is a comparatively conventional design problem.

Where this could actually be used#
1. Browser-extension models rolled out department by department
Using a browser AI extension to vertically uplift existing systems without touching them:
- Guided walkthroughs at the point of service, with root-cause explanations when something errors out.
- Assisted troubleshooting for customer-service staff answering real customer questions.
- Surfacing the exact clause/source behind a procurement rule during the purchasing process.
- Giving analysts a “fine-tuned” explanation of what a given reporting metric actually means.
2. Building a shared knowledge base across different business lines
Using an LLM to build out a knowledge base sidesteps two common pain points.


