How to Use the ‘Anti-Goal’ Prompt Trick to Keep ChatGPT in Line

Often, AI systems like ChatGPT, Claude, and Gemini tend to overstep their boundaries because they aim to please you excessively. For instance, an AI might completely rewrite a document when all you needed was specific feedback, or it might generate an entirely new recipe instead of helping you find suitable ingredient substitutions.

One might assume that instructing the AI on what not to do in your prompt would prevent this. However, this approach can backfire, as the AI, eager to deliver a helpful reply based on your initial words, might downplay or ignore your restrictions altogether.

The key is to craft your prompt in a manner that compels the AI to pause and give appropriate attention to each part of your request. An effective method is to label each segment to specify its purpose.

Modern AI chatbots such as ChatGPT, Claude, and Gemini can recognize “markup” elements that serve as cues for understanding the structure of your prompt. These elements communicate whether a section provides background information, detailed instructions, or restrictions on the AI’s actions.

In this approach, we’ll employ XML markup, using open and close tags to delineate different areas within your prompt. For example, one set of tags can define the main goal—what you want the AI to accomplish—while another set can specify the “anti-goal”—what the AI should avoid doing.

Suppose you want feedback on a cover letter you’ve already written for a job application, rather than asking the AI to write or revise the letter itself. Your prompt might look like this:

Expert Career Coach and Hiring Manager

Review the attached cover letter for the [Insert Job Title] position. Assess whether the introduction is compelling, if the tone is suitable for the industry, and if the experience connects effectively to the job requirements. Highlight any sections that seem too generic or lack specific evidence.

Do NOT rewrite any parts of the cover letter. Do NOT produce a revised version. Focus only on providing actionable feedback in a bulleted list, avoiding minor grammar or typo corrections.

This prompt structure, especially with role designation and explicit instructions within XML tags, guides the AI to focus solely on giving you feedback, preventing it from going beyond its intended task (such as rewriting your letter).

Here’s another example:

Travel Guide

Identify five distinct neighborhoods to stay in during a week-long visit to Tokyo, emphasizing areas rich in street food and with convenient transit options.

Avoid creating detailed daily itineraries. Do not recommend specific hotels or restaurants. Keep descriptions of each neighborhood under three sentences.

Using this prompt with ChatGPT’s latest GPT-5.5 Instant model resulted in clear, targeted responses, such as:

Shinjuku
A vibrant hub filled with late-night alleys, standing bars, and yokocho streets offering casual bites. Excellent transit connectivity via Shinjuku Station makes it easy to explore everywhere in Tokyo.

Ueno
Known for its traditional flair, open-air markets, and affordable street snacks around Ameya-Yokocho. Ueno Station connects multiple JR and subway lines, including routes to Narita Airport.

Asakusa…

The core insight is that clearly defining what not to do—and expressing this through structured XML tags—is a powerful technique to ensure the AI stays aligned with your specific needs.