What an AI agent actually does when it builds your financial plan
"An AI agent builds your financial plan" sounds like it could mean almost anything — including, to a skeptical reader, "an LLM makes up a number and hopes it's right." That's not how it works, and the actual mechanism is worth being specific about.
Two layers, doing two different jobs
The system has a conversational layer and a calculation layer, and they don't share responsibilities.
The conversational layer — the part that feels like "AI" — listens to how you describe your household, your income, your accounts, your goals, and extracts that into a structured profile. It asks follow-up questions when something is ambiguous. What it does not do is compute a financial figure. It routes and organizes; it doesn't calculate.
The calculation layer is a deterministic pipeline: a pure function of your confirmed profile and a set of published, sourced assumptions (tax brackets, contribution limits, CPP/OAS rates, and so on). Same profile, same assumptions year, same output — every time. Nothing probabilistic, nothing that depends on how a language model happened to respond that day.
The confirmation step in between
Between those two layers is a deliberate pause: nothing is calculated until you've confirmed every figure the intake extracted. If it misheard your income or misread an account balance, the confirmation step is where that gets caught — before it propagates through six planning areas' worth of math.
This makes the process slower than a tool that just runs with whatever it parsed. That's intentional. A plan is only as good as its inputs, and a wrong number confirmed once is a lot easier to catch than a wrong number that silently produced a wrong plan.
Why this combination is the actual point
Neither piece alone would be as useful. A purely conversational tool without a deterministic engine behind it would be guessing at math. A purely deterministic tool without conversational intake would require you to fill out a form built by someone who guessed at every field you might need — the usual complaint about financial-planning software. The combination — natural conversation for input, deterministic and reproducible calculation for output, with a confirmation step holding them together — is what "AI agent" means here, specifically, not as a buzzword.
Mensari is an educational decision-support tool, not licensed financial, tax, or legal advice. It illustrates tradeoffs based on the assumptions you provide — always confirm decisions with a qualified professional before acting.
Mensari walks through this exact sequence — conversation, confirmation, deterministic plan — in more detail.