Lock the Stack
Stop it choosing your tools for you
Pass · ChatGPT, Pro · September 27, 2026
Partial · Claude.ai, Fable 5.1 Max · September 27, 2026
What it does
Names the exact tools before a single line gets written, and bans quiet swaps later.
When to use it
The very first thing you say on a new build.
The prompt
Paste it, then fill in the <angle brackets>
Before you write anything, say back to me that you will use ONLY:
- <the framework, and the exact version>
- <how it gets styled>
- <the database, and how the app talks to it>
Do not install anything else without asking me first.
If you think one of these is the wrong choice, say so now
and stop. Do not quietly swap in something else.Ways to use it
- Paste it into your rules file so it applies every time
- Copy the exact versions out of your lockfile so there is no guessing
- Flip it around: ask what it WOULD have picked, and why
Test log
Each prompt was pasted into a fresh private chat with memory off and graded against pass standards written before the run (all of them, dated).
| Date | Tool | Model | Result | What happened |
|---|---|---|---|---|
| September 27, 2026 | ChatGPT | Pro | Pass | Repeated the three tools with exact versions, added nothing, and said email sending would need an extra service only with approval. Wrote no code. |
| September 27, 2026 | Claude.ai | Fable 5.1 Max | Partial | Stopped before code and asked about email, but said back Next.js 15.5 instead of 15.5.4 (it argued for a security patch) and said it would add TypeScript unless told not to. |
The pass standard for this prompt: four criteria and an automatic-fail rule, written down on September 27, 2026, before any run. A second version for a reworded prompt was written on September 28, 2026; nothing has been graded against it yet.
Related words
- constraint block — The part of your prompt that says what the AI is not allowed to do: which tools, which files, which lines it must not cross.
- intent drift — The gap between what you asked for and what the AI reasonably assumed you meant.
- slopsquatting — Registering a package name that AIs commonly invent, so that when one invents it, what arrives is the attacker's code.