can I use AI to summarize long documents and how accurate is it?

Yes, you can use AI to summarize long documents, and it's surprisingly good at it. But you need to treat the summary like a smart intern's work, not a finished product. It will get the main ideas right most of the time. It might miss a crucial nuance or a specific number buried in paragraph 47. Think of it as an 80/20 tool. It does 80% of the reading work in seconds, but you're still on the hook for the final 20% of checking what matters. The process is usually simple. You paste the text into a tool like ChatGPT or Claude and ask for a summary. For a 20-page report, it can give you a half-page overview almost instantly. The real skill is in how you ask. A generic 'summarize this' will give you a generic, sometimes bland result. You'll get much better output if you give the AI a specific goal. For example, instead of 'summarize this contract,' try 'Act as a lawyer and summarize this contract, highlighting any unusual clauses, automatic renewal terms, and liability caps.' This focuses the AI like a laser. I've used this to quickly compare multiple research papers. I'd ask the AI to 'extract the primary finding, the sample size, and one key limitation from each study and put it in a table.' That's something that would take me an hour, done in 30 seconds. The accuracy is the tricky part. According to a 2024 study by researchers at Stanford, AI summarization tools are highly accurate for identifying main topics but can 'hallucinate' or make up specific details about 3% to 5% of the time. That's a small number, but if it's a detail in a legal document or a medical report, it's a big problem. So, a good rule of thumb: use AI to find the needles in the haystack, then use your own eyes to confirm they're actually needles and not just shiny pieces of hay.