You'll finish with: An offers file that stops Claude inventing prices.
The most embarrassing thing an AI setup can do is quote a client a price you never agreed to. This one file prevents it.
Where does the number come from?
Without the file it will still give a number. It just makes one up, and it'll sound completely reasonable — which is exactly what makes it dangerous.
Two reasons. It keeps CLAUDE.md short, and it gives you one file you can lock down so no agent can edit your pricing — you'll do that in the last chapter.
"Source of truth" means: if it's not in this file, it doesn't exist. Claude quotes from here or it asks you. It never makes a number up.
Everyone lists inclusions. Almost nobody lists exclusions, and that's where scope creep comes from. Write the "not included" list first if you have to.
In the browser there are no folders — the "file" is just another piece of project knowledge. It does the same job: one place the prices live, so Claude reads them instead of guessing.
business.offers.md — see the note below if your computer keeps adding .txt.business and a file inside it called offers.md.Saving a file with the right name. Windows Notepad adds .txt unless you stop it: in the Save dialog set Save as type to All Files, then type offers.md. On a Mac, TextEdit needs Format → Make Plain Text first. A .md file is just a plain text file — nothing special opens it.
Ask it to quote something you don't sell. It should say it doesn't map to an offer and ask you — not produce a number.
If it invents a price anyway, your CLAUDE.md line is missing or the file is somewhere it can't see.
# Offers
## [Offer name]
Who it's for: [client type and their pain]
Included:
- [item]
- [item]
NOT included:
- [item]
Price: $[low] – $[high]
Top of range when: [conditions]
Typical timeline: [duration]
# What we don't sell
- [thing people ask for that we don't do]