How to Prompt Opus 4.7

Older Claude models would fill in what you didn't say. Opus 4.7 doesn't. It reads your prompt exactly as written, executes what you asked for, and stops. If two instructions conflict, one loses. The gap between what you meant and what you wrote is now your problem to close.

Why this changes how you write prompts

What changed

Lead with the outcome, not the task

Why it matters

❌ Weak

✅ Strong

The length follows what you ask for

How to control it

Every gap in your prompt is a decision Claude makes for you. Opus 4.7 won't soften or second-guess that decision - it just makes it and moves on. Specify everything you care about or accept whatever Claude picks.

The six things to always pin down

Before you send any prompt, check for these

What a fully specified prompt looks like

❌ Before

✅ After

Write your exclusions as hard rules

Why exclusions matter more now

Example with exclusions built in

Two moves that compound every time you open Claude: getting pushback before you commit to something, and pasting a reference doc that shapes every response without you having to re-explain yourself.

Make Claude push back on your plans

Claude has opinions but won't share them unless you ask

When to use it

Build a context doc and paste it at the top

What it is

What to put in it

How to use it

Example structure