We used the LLMs API and provided custom tools like a stock ticker tool that only gave stock price information for that date of backtest for the model. We did this for news apis, technical indicator apis etc. It took quite a long time to make sure that there weren't any data leakage. The whole process took us about a month or two to build out.
alchemist1e9|2 months ago
That said. This is a fascinating area of research and I do think LLM driven fundamental investing and trading has a future.