Home › Resources › Marketing Source of Truth
A marketing source of truth is the one document ChatGPT or Claude reads before it writes a word for your business. This one builds itself: paste the prompt, answer six rounds of questions, and half an hour later you have it.
Form not working? Use the original signup form.
Unlocks instantly. You also get G's Marketing Letters, one short letter every weekday. No upsell behind it. Privacy.
Operating rules for the AI
Draft, research, summarise and schedule to a queue: no need to ask.
Marketing Source of Truth
Interview me, then write it
You are going to interview me about my business in six rounds, one round at a time. Ask four or five questions per round. Rough, honest answers are fine. After each round, summarise what you have locked in and flag anything that contradicts an earlier answer, then wait for my correction before the next round.
paste this in, start talkingThe problem
You typed "write a LinkedIn post about my accountancy firm" and got 150 words that could be any accountant in Britain. "In today's fast-paced business landscape." Straight in the bin.
That is not the tool being bad. It is the tool not knowing you. ChatGPT has read the whole internet and none of it was about your business, your customer, or the way you actually talk to people. So it gives you the average of everyone.
Where it gets expensive
You add "we're a friendly firm in Ipswich, keep it casual, no jargon" to the top of every request. By Thursday you have stopped bothering. The output drifts. Every post sounds a bit different because every prompt was a bit different.
Then you set up an automation, or someone sells you one, and now the wrong thing is being produced reliably, five times a week, in your name.
Banned words: leverage, synergise, "game-changer" and hype superlatives generally, corporate filler, anything that sounds like a LinkedIn guru.
The fix
A source of truth is one document with everything the AI needs to know before it writes: who you are, who it is for, what you promise, what you are against, how you sound, what you will never say, and what it is allowed to do without asking you.
You paste it in first. Then you ask for the post. The gap between what you were getting and what you get now is the whole trick, and it is why the Prompt Pack says "paste your context first" at the top of every prompt.
The catch with most templates is that nobody fills them in. So this one interviews you instead. You talk, it writes, you correct. Half an hour.
What you get
Paste it into ChatGPT or Claude. It runs six rounds, one at a time, summarises each and waits for you to correct it, then writes the finished document. This is the exact method that built mine.
Round 5 is voice. Ask me to take a common piece of advice and say it the way I would actually say it out loud. Keep that answer word for word: it is the voice sample every future draft is checked against.
For people who would rather type. Every section has the questions from the interview built in, one real example line from my own document, and a copy button so the finished thing pastes into any AI tool.
04 Positioning. Example: "Marketing advice that's about actual leads and sales, not vanity metrics, not hype."
The section nobody thinks about until something goes out with their name on it. What the AI may do unasked, what always needs a human, and the ban on invented numbers. Printable. Stick it above the desk.
Needs a human, every time: anything published, anything sent to a customer, anything with a price in it.
What changes once it exists
The receipts
30 August 2026, 06:53. I asked Claude to interview me instead of handing me a template. Six rounds, one at a time, answered out loud with a coffee. By 07:24 the questions were done. By 07:27 the document existed.
Every page on this site, every one of the daily letters, every carousel and every image has been checked against that document since. It has an update log with over 80 dated entries. When something the AI made looked wrong, the fix went in as a rule so it could not happen twice. This site is the receipt.
It is also how I worked at the agency and how I work now with my own clients: the first thing built for a new client is a source of truth, before anyone touches a page, a post or an ad. It is the difference between a client's marketing and the average of their sector's. I am giving you the same thing, minus the invoice.
free. that's the whole point.
Yours for an email
Drop your email and the page unlocks instantly. It lands in your inbox too, so you can find it again. No card, no trial, no upsell waiting behind it.
Where should it go?
Form not working? Use the original signup form.
You'll also get G's Marketing Letters: one short, useful letter every weekday, no upsell behind it. Unsubscribe any time. Privacy.
Either works, and so does Gemini. The interview prompt is plain text. Paste it into whichever one you already use, answer the questions, and it writes the document for you.
About half an hour if you talk (the microphone button in ChatGPT or Claude is fine). Longer if you type. Round 1 on its own is five minutes and worth doing tonight.
No. Brand guidelines tell a designer what colour the logo is. This tells an AI who your customer is, what you promise, how you sound, and what you would never say to a customer. Guidelines are one section of it.
It is built for you. It assumes the owner is the marketer, the budget holder and the person typing into ChatGPT at 9pm. The questions are written for a business, not a marketing department.
Your email address and, hopefully, a reader. You also get G’s Marketing Letters, one short letter every weekday. There is no upsell waiting behind the form.
Already got yours? Put it to work with the AI Prompt Pack (every prompt starts with "paste your context first"), or read the guide on how to use AI for marketing when you've got no time and no marketer.
