- Claude.ai account
- Access to a Project, or account Settings
Find where to paste it
Decide the scope first. This instruction can live in two places, and they behave differently.
- a.Account Settings applies the instruction to every new chat on your account, not just one project.
- b.A specific Claude Project's custom instructions applies it only inside that project, leaving your other work untouched.
If only one project keeps hitting the wall, scope the instruction to that project instead of your whole account. It keeps your other Claude conversations at their normal tone.
Copy the instruction block
Copy the text below exactly. Do not shorten it or rewrite it in your own words, the specific phrasing is what keeps Claude from drifting back to verbose defaults after a few turns.
Paste and save
- a.Open the custom instructions field you chose in Step 1.
- b.Paste the block in as-is, with no edits.
- c.Save the field.
Confirm it is active
Send a normal working message, something you would have asked anyway. Check the reply against these three signs.
- No preamble before the actual answer
- No code appears unless you asked for code
- Repeated context gets summarized instead of restated in full
By the third message inside a project running this instruction, the difference in reply length becomes obvious. If message three still reads like message one, revisit Step 1 and confirm the field actually saved.
Tighten further when needed
The instruction has a built-in escalation. Say either trigger word inside any message in the thread to force a stricter pass on that reply.
- concise mode, for a single blunt answer with no framing
- optimize, when you want Claude to also flag files or context in the project that no longer need pulling in
FAQs
Q. Will this make Claude refuse to write code?
No. It stops Claude from generating code you did not ask for. When you do ask for code, it still writes it, but favors minimal diffs over rewriting whole files.
Q. Does this work in every Claude interface?
It works anywhere a custom instructions or system prompt field exists: account Settings, a Claude Project, or an API system prompt.
Q. Why do long project threads hit token limits in the first place?
Every reply in a thread resends the full conversation history. Fluff, repeated explanations, and unrequested code all get resent turn after turn, so the token cost compounds long before you reach your actual question.
Q. Can I run this alongside other custom instructions I already have?
Yes. Add it below your existing instructions rather than replacing them. If two instructions genuinely conflict, the one listed last generally takes priority, so keep this one at the bottom if brevity should win.
Troubleshooting
| Symptom | Likely cause | Fix |
|---|---|---|
| Replies are still long after saving | The field was not saved, or you pasted it into the wrong project | Reopen the field and confirm the text is present, then start a new chat inside that project |
| Claude stopped explaining anything at all | The instruction is being applied too literally on a task that genuinely needs walkthroughs | Ask directly for more detail in that message. A specific request always overrides the standing instruction |
| Code still appears unprompted | Your message implied a code change even without asking outright | State explicitly when you do or do not want code included in the reply |
| Instruction seems to stop working after many turns | Very long threads can dilute a standing instruction's weight | Start a fresh chat inside the same project so the instruction is read at full strength again |
Version history
| Version | Date | Change |
|---|---|---|
| 1.0 | September 2026 | Initial SOP published |