Do You Need an llms.txt File? What It Does, What It Does Not, and What to Fix First

The llms.txt file is a short markdown document describing a site and listing preferred pages for language models to read. While easy to generate, its actual impact remains limited. Separately, Claude Code utilizes a /compact command for session summaries. The cost of this operation depends on the cache status rather than context size. Warm caches reduce costs significantly, whereas resuming old sessions requires reprocessing full history as uncached input, increasing the overall expense.