01
What Claude is, in plain English
Who makes it, how it differs from a search engine, and the one mental model that saves people a fortnight of confusion.
ReadNotes on Claude, written for people who run things.
Twenty short pieces, none of them longer than a coffee. No jargon, no hype, and no pretending the tool is better than it is. If one of them saves you a meeting, it has done its job.
Three ways in. If you have never really used it, start with what Claude actually is. If the licences are already paid for and half the team has quietly stopped opening it, skip to why the results are patchy. If you are weighing up whether to spend anything at all, the four questions are the thing to read, and two of them cost nothing to fix.
Starting out
If you have never really used it02
How Claude works, without a single equation
One mechanism sits underneath every strange thing you have noticed, and it takes five minutes to understand properly.
Read03
What a context window is, and why bigger is not better
What it holds, what it does not, and why filling it up is usually a mistake rather than an achievement.
Read04
Where you can use Claude, and the one place to ignore
A short map for someone who wants to know where to type, not what the whole product range is called.
ReadChoosing
Models, versions, and rival tools05
Claude vs ChatGPT vs Gemini: the comparison nobody publishes
Three assistants far closer to one another than the comparison articles admit, and the one difference anybody has measured.
Read06
Which Claude model should you use
What the tiers are for, what they cost relative to each other, and why most people never make this choice at all.
Read07
What the version numbers mean
Two separate things are packed into every model name. One is a decision you make, the other is just a date.
ReadJudgement
Knowing what to trust, and what to keep away from it08
Why Claude gets things wrong, and why it sounds so sure
Hallucination is a misleading word for something quite ordinary, and knowing what it describes changes how you read the output.
Read09
What Claude is genuinely good at
The tasks it handles reliably, drawn from what people produce with it in a real week rather than from any product page.
Read10
What Claude is bad at, and which limits are permanent
Five things it will not do well for you, and which of them the next release is not going to fix.
Read11
When not to use Claude
Five categories I tell senior teams to keep away from it, including one that costs nothing measurable and matters most.
ReadMaking it stick
Why it works for some teams and not others12
How to write a prompt that works
Four things every decent prompt carries, from the same before and after example I use in sessions.
Read13
Where the time comes back
About an hour a week at first, from the dullest parts of your diary, and a fair slice of the rest is not a saving at all.
Read14
Why your team's results are patchy
Two people swear by it, the rest opened an account once, and nobody raises it because raising it sounds like a confession.
Read15
Do you need training?
Four questions to answer before you spend anything. Two of them you can settle yourself on a Friday afternoon.
ReadBy role
Where it lands differently depending on your job16
Claude for founders
What to do when nobody in the room is neutral, and why the useful setting is the one that argues back.
Read17
Claude for legal and risk teams
Genuinely useful on contract summaries and clause comparison. First pass, never the final word.
Read18
Claude for people and talent
Strong on drafting, weak on judgement, and the raw material of the work is somebody's livelihood.
Read19
Claude for comms and marketing
The function that adopted these tools fastest is the one now paying for it. Sounding like everyone else is the risk.
Read20
Claude for strategy and operations
The process that lives in one person's head, and the afternoon nobody has spare to get it written down.
ReadRather just ask someone?
Twenty articles is a long way round to answer one question. Tell me in three lines what is not working and I will tell you whether training moves it, which two of these to read instead, or that you are already fine and should keep the budget. I have given all three answers this year.
Write to meA reply from me, not an assistant, inside two working days. If you would rather take something to your leadership team first, there is a one-page version of the four questions made for exactly that.