I’m not sure if that would work in your use case, but you could classify each line into a value using an LLM then hard code the trends you are looking for.
For example if you’re analysing something like support tickets. Use an LLM to classify the sentiment, and you can plot the sentiment on a graph and see if it’s trending up or down.
I wanted to figure out reasonable values for range of daily/hourly precipitation for https://weather-sense.leftium.com. Claude wrote a script to call the Open Meteo API to collect hourly stats for a few cities for an entire year (8000+ rows), then just reported the 80th, 90th, etc percentiles and recommended ranges.