Ask Ronnie.
Not the power user.
↳ annotation: handbook → how-to → exact Dutch UI terms01 / The Challenge
Eva de Kemp is Brownys’ Rentman power user, the colleague everyone asks when they need to know how the platform works. The same questions came in all day: “how do I create a project?”, “why is my material turning red?” Every interruption pulled her off her own work.
02 / The Protocol
We built Rentman Ronnie, a Dutch-speaking AI colleague in ChatGPT, trained on Brownys’ own 36-page Rentman handbook. Ask a how-to question and he answers step by step in the exact Dutch UI terms. Searching gear and live stock came later, as a bonus.
The Resolver Engine
Ronnie is knowledge-base-first. Most questions are how-to, and he answers them straight from the handbook with the exact Dutch UI terms. When a question needs live stock he resolves the name to an ID locally, then calls the read-only API and does the maths himself. Watch a few queries walk the pipeline.
The Co-Build
This was not a hand-off. Eva, a non-technical Ops lead, brought the domain knowledge and ran fine-grained QA in batches; Protocol brought the architecture. Ronnie hardened version by version, each fix traceable to a real failure in the field.
Eva's first attempt
Eva had built a rough V1 herself, a 12-page prompt the bot kept ignoring. Protocol takes over the architecture and rebuilds it from the ground up around her knowledge.
A Colleague, Not a Helpdesk
Ronnie talks like a coworker, not a support ticket. Dutch first, concrete steps with the actual UI element names, and the API kept invisible. He never claims 100% certainty: every availability answer ends with “check the planner to be sure.”
When a question falls outside scope, like an invoice dispute, a permission problem or a bulk change, he doesn’t bluff. He points the user to a power user like Eva or Floor, and gets out of the way.
Results
Searchable by name, code or category.
Iterations on real user feedback.
Pure Custom GPT. No n8n, Supabase or backend.
Internal Rentman questions Ronnie catches.
Field Report
“I used to be the human search engine for Rentman. Now the team asks Ronnie first, and I get my own day back. He gives them the answer and an honest nudge to double-check the planner, which is exactly how I would answer it myself.”
Eva de Kemp
Operations, Brownys Event Productions
Next Case Study · CRB-03