Compose the first message to the AI that GIVES CONTEXT (does not ask for analysis yet). Return JSON {"whatData":"...","columns":"...","goal":"..."}: whatData - what kind of data is this, where does it come from and what does ONE line mean; columns — list the columns in human language with units (rubles, pieces, date); goal - what you want to get in the end.
AI doesn't see your spreadsheet the way you do. Until you explain, he’s like a new employee who’s been given a file without a word: the numbers are there, but there’s no point. The mechanics are simple - the model builds an answer from your words, so the more precise the context, the less it invents. Always say three things: what kind of data this is and where it comes from, what ONE line means, and in what units the numbers are (rubles, pieces, percentages). Insider: The most underrated question is “one line equals one what?” Say “one line is one order” or “one line is one day”, and the AI will stop adding up the incomparable. Second trick: don’t ask for analysis in the first message. Give context first and ask him to retell how he understood the data - this way you catch misunderstandings before you get a beautiful but incorrect conclusion. A typical newbie mistake: “analyze my data” without a description. AI will guess the structure and confidently count nonsense.