How it actually works
A working guide to generative and agentic AI in finance
What generative AI and agents actually do in finance, how the machinery works, and the checks that follow directly from it. Not prompt tricks, and not hype.
Twelve topics, from how a model produces an answer to governing an agent that acts on its own, each linking the fuller write-ups on this site and the ebook the material comes from. Openly available.
Financial institutions are being sold generative AI that will transform their work, and agents that will do the work for them. Some of it is useful. Some of it is hype. In finance the difference matters, because these systems can affect customers, records and money.
I do not teach prompt tricks. In class I call that approach prompt and pray, and it does not hold up over time. A good instruction helps, but it will not replace understanding how the system works, or the checks you need before you let it act. This guide explains the machinery, as plainly as I can manage, and the checks that follow directly from it.
I spent years supervising AI risk at the Monetary Authority of Singapore and wrote Singapore's AI risk management guidelines for the financial sector. Before that I inspected quantitative models in banks. The examples here come from finance because that is the work I know. You do not need to build a model to follow it, but you should come away able to ask a team what its system does, what could go wrong, and how it would know.
I keep this openly available rather than behind a sign-up. Each topic opens with a question, so try to answer it before you open the explanation. Use the contents below to jump to a topic, or step through them in order, and each one links to the fuller write-ups on this site and to the ebook it draws on. If you would like to follow me for more of such stuff, come find me on my Substack.
I am keeping this as a live document, last updated 28 October 2026, so drop me a note (at gary@quaintitative.com) anytime if you want to add or correct something. All of this is deliberately boring. That is the point. And if you think I have got something wrong, tell me. I would like to learn more.
What this covers, and what else is here
This guide stays close to the machinery: how generative AI and agents work, where they help in finance, and the checks around one chatbot or one agent. The wider programme that governs all of a firm's AI is written up separately, and openly, here. A few of the highlights:
The companion self-paced courses. AI risk governance for risk and control functions, for the second and third line, and the executive guide for the board and senior management.
The AIRG and the wider Singapore picture. The AIRG explained, the final AIRG, and the complete guide to AI risk management in finance in Singapore.
The AI risks, each set out in full. AI risks in finance, including made-up answers, prompt injection and data leakage.
The use cases in finance. AI use cases in finance, and the use-case explorer to find one by task.
The plain-English ebooks. This guide draws on Agentic and Generative AI for Finance; the full set is on the books page.
Taken together, that is most of what someone who builds, buys or reviews AI in finance needs to get going, openly available, in one place.
Contents
Part one · how it actually works
Part two · generative AI in finance
Part three · agents
Part four · making it safe to use
Part one · Topic 1 of 12
From prediction to generation and action
Machine learning, generative AI and agents, and what changes when a system can act.
What is a language model actually doing, and what changes when it can act rather than just answer?
How the capabilities build. Machine learning predicts from data, such as whether a borrower will repay. Deep learning reads more complex patterns, such as documents or transaction sequences. Generative AI produces content, such as a draft credit memo. Agents use a model to select steps and call tools to carry out a task, such as gathering information, drafting a payment and submitting it for approval. The categories overlap and build on each other, and moving down the list does not automatically make a system better.
What changes when it can act. A chatbot gives a wrong answer on a screen, and a person can still ignore it. An agent takes a wrong action in a system, and it is already done. The convenience and the risk are the same feature. A research assistant that can only read documents has fewer ways to cause harm than one that can also send emails or place orders.
Check the whole task. An agent takes several steps for one request, and an early mistake flows into the later ones. If ten steps each succeed ninety-five per cent of the time and every one must succeed, the whole task completes about sixty per cent of the time. So measure success on complete tasks, and check that the system stayed within its permissions. Before reaching for an agent, ask whether the steps could be written as an ordinary workflow; a known sequence is easier to test and control.
Related on this site: agentic and generative AI for finance, the five S's of AI, and governing agentic AI.
In the ebook: Agentic and Generative AI for Finance.
Want to go deeper?
The ebook this draws on. The full treatment, with the worked finance examples and the references, is in Agentic and Generative AI for Finance. The companion books cover the wider AI risk management programme.
IBF-accredited courses. The deep-dive and technical courses I designed and teach are IBF-accredited and listed on the IBF Programme Finder, delivered through the Association of Banks in Singapore and the Singapore College of Insurance: Banks (deep dive), Banks (technical) and Insurers (deep dive).
Courses I run directly. I also run courses in-house for a single firm now, and maybe as open cohorts one day, including a technical hands-on day on building and testing these systems, and sessions for risk and control functions, leaders and boards. See the courses.
After subsidies, the accredited courses come to roughly S$200 to S$300 a participant. Direct engagements, for cohorts of around 40, come to something similar per person.