I built a tool where 5 AI "board members" challenge a founder's numbers. The trick was keeping the math out of the LLM

Early founders rarely have a CFO or an experienced board to push back on their plan. So I built Board15: you enter MRR, burn and cash, deterministic formulas calculate runway and risk, and then five AI personas (CEO, CFO, CMO, COO, Devil's Advocate) interpret the results from their own angle. Biggest lesson: letting the LLM do the calculations produced confident nonsense. Moving all the math into fixed formulas and using the model only for interpretation made the output far more trustworthy. Would love feedback on the report format. Try it: board15.io