One request, all the way through

Here is the loop with tools in it, from start to finish. This is an example written for the book. The business, the people, the files and the figures are made up.

Dana runs the office of a small landscaping company. She opens the AI assistant her company uses and types: “Which of last month’s invoices are still unpaid? Draft a short reminder to each customer and send them” (step 1). The harness builds the briefing (step 2). It includes the company’s instructions (“You help the office staff of a landscaping company”), the two tools the model may ask for, read_file and send_email, a saved note that Dana likes a friendly tone, and her message.

The model reads all of it. It predicts that the right next thing to write is a request: read the file invoices-june.xlsx (step 3). Then it stops. The harness checks its rules. Reading files in the shared folder is allowed without asking, so it opens the file and adds what it found to the briefing: three invoices unpaid, from the Ortiz, Brennan and Lee households (steps 4 and 5).

The model reads the longer briefing and goes around again. It drafts three reminders and asks to send_email three times (step 3 again). This time the rules say that sending needs a person’s approval, so the harness shows Dana the drafts and asks (step 4). She approves two. She refuses the third, because Mr. Lee paid by check yesterday, which the spreadsheet could not know. Two emails go out, and the refusal goes back into the briefing as a tool result (step 5). The model reads it and writes its answer: two reminders sent, one held back at her request, and a suggestion to mark the Lee invoice paid. The harness shows her the answer (step 6).

Now look at who did what. The model never opened a file or sent an email; it wrote requests. The harness ran every action and stopped at the one step its rules marked as risky. The tools did the reading and the sending. And the error that mattered, a reminder to a customer who had already paid, was caught by Dana at the gate, because she knew something no file held. Change any one part and the outcome changes. Without the file tool, the model could only guess who owed money. Without the approval step, Mr. Lee gets a reminder he doesn’t deserve.