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One Tool a Week

One AI tool a week, tried on ordinary work

A short letter every Tuesday: one AI tool tried on ordinary work for a week, with what it was good for, what it got wrong and what it cost.

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Latest issues

One new issue every Tuesday: one tool, one week, and what I found.

  • A week with a meeting note taker

    I let a note taker listen to every meeting for a week. It was good at action items, wrong about who said what, and the free plan was enough.

    Nov 10, 2026 · 9 min read

  • A week with a chat assistant for study notes

    I used a chat assistant to turn a messy lecture page into a clean summary. It was good at structure and wrong about two dates. Cost: the free plan.

    Nov 3, 2026 · 8 min read

  • A week with a spreadsheet helper

    A helper that writes formulas from plain sentences. Good for sums and lookups, wrong once on a date format. Cost: a small monthly fee I cancelled.

    Oct 27, 2026 · 10 min read

Downloads and courses

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Download as soon as you pay. Yours to keep.

  • PDF

    Spiral notebook with speech-bubble cover standing upright

    Prompt Notebook Template

    A notebook page for each prompt you try: what you asked, what came back, what you changed and whether it worked.

    $8View
  • PDF

    Split frame of a blurred comparison sheet and a stopwatch

    Tool Comparison Sheet

    One sheet to compare two tools on the same task: time saved, mistakes found, cost and whether you would use it again.

    $5View
  • PDF

    Seven sticky notes with ticks in a row on blue

    First Week With AI Checklist

    A day-by-day checklist for your first week using an AI tool at work, with the questions to ask each day.

    $6View
  • PDF

    Hands writing on a notes page with index tabs

    Meeting Notes Template Pack

    Five note pages for meetings, from a quick check-in to a long planning session, made to fill in by hand or on screen.

    $9View
  • PDF

    Macro of a steel padlock with frost on it

    AI Privacy Checklist

    What to check before you paste work or study material into a tool: where it goes, who can read it and how to delete it.

    $7View
  • PDF

    Laptop screen showing blurred spreadsheet cells and chart

    Spreadsheet Helper Prompt Pack

    Forty prompts for asking an assistant to write, explain and check spreadsheet formulas, with a worked example for each.

    $12View
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About

Hello, I’m Daisuke

I write from a small flat in Sapporo, at a low table with a laptop, a mug of tea and a lot of snow outside. By day I do ordinary office work: emails, meeting notes, spreadsheets, the odd report. When AI tools began to turn up everywhere, I wanted to know what they were actually good for on days like mine.

So I started the letter. Each week I pick one kind of tool, such as a writing assistant, a meeting note taker or a chat assistant, and use it on real work for seven days. Then I write down what it did well, what it got wrong and what it cost. I do not name products and I do not take money from tool makers. I would rather you could use the notes with any tool.

What I sell are the things I use to keep the trials fair: a prompt notebook, a comparison sheet, checklists and prompt packs, and two short video courses. They are plain and they do not need any one tool.