Google’s AI Max introduces a powerful feature for advertisers: text customisation. By opting in, advertisers allow Google to generate new ad assets automatically, including Responsive Search Ad (RSA) headlines, callouts, and sitelinks.
This can save time and expand testing opportunities, especially for large or busy accounts. But many advertisers hesitate because AI-generated copy can feel inaccurate, generic, or outside brand guidelines.
That’s why one of the most important developments in AI Max is the introduction of text guidelines or instructions that help shape how Google’s AI writes your ads. Used properly, these guidelines can transform AI Max from a risky automation tool into a reliable creative assistant.
Here’s everything you need to know about AI Max text guidelines, how to test them properly, and use them to improve performance without sacrificing brand quality.
Why Text Guidelines Matter
AI can generate copy at scale. But scale without direction often creates noise.
Without clear guidance, automated assets may:
- Misrepresent your business
- Use claims you cannot legally make
- Sound generic or low-quality
- Mention prices or offers incorrectly
- Target the wrong audience
- Ignore your brand tone
- Overpromise results
- Produce weak click-through messaging
That creates extra cleanup work and can hurt campaign performance.
Text guidelines solve this by giving Google’s AI boundaries and direction.
Think of them as:
- Brand rules
- Compliance guardrails
- Messaging priorities
- Creative strategy prompts
Instead of hoping the AI “gets it right,” you proactively shape the output.
The Two Main Types of Controls in AI Max
1. Term Exclusions
Term exclusions are simple and highly effective.
You can add up to 25 words or phrases that should never appear in generated assets.
Use this for:
- Competitor names
- Trademarked terms
- Misleading claims
- Discount language
- Sensitive or restricted phrases
Example:
If an advertiser helps with trademark filing and AI creates copy calling them a “USPTO lawyer,” that would be inaccurate because the USPTO is a government agency.
Adding USPTO to exclusions immediately blocks similar mistakes.
2. Messaging Restrictions
Messaging restrictions are more nuanced.
You can add up to 40 written instructions with 300 characters each that guide the AI. These tell the AI how not to write or how to frame messaging.
Examples:
- Do not mention prices in ad copy
- Avoid location names unless specified
- Focus on B2B decision-makers, not consumers
- Do not make absolute performance claims
- Maintain a professional, expert tone
These restrictions are where real strategic control happens.
Why Most Advertisers Struggle With Guidelines
The challenge is simple:
You can’t predict every possible way AI might write something wrong.
Even if you block “discount,” the AI might say:
- Save more today
- Lower your costs now
- Affordable pricing available
Even if you ban prices, it may imply them.
That’s why strong AI Max guidelines should be built through testing, not guesswork.
Best Way to Build Strong Guidelines
Step 1: Generate Sample Ads
Use Gemini or another AI tool to create headlines and descriptions for your business.
Review the outputs and note anything that feels:
- Inaccurate
- Too aggressive
- Off-brand
- Legally risky
- Irrelevant to your audience
The goal is to identify patterns.
Step 2: Turn Problems into Rules
Create one rule per issue.
Instead of writing:
“Mention trials clearly, don’t discuss pricing, don’t exclude smaller clients.”
Break it into:
- State trial length clearly
- Do not mention pricing
- Do not exclude smaller businesses
Clear, focused rules work better.
Step 3: Re-Test the Output
Run new ad examples using your updated rules.
Check whether the new assets are:
- Accurate
- On-brand
- Clear
- Relevant
- Click-worthy
Refine until quality improves.
Where AI Max Often Performs Best
Many advertisers find AI-generated ad group-level assets more useful than RSA headlines.
These include:
Callouts
- Free Demo
- No Setup Fees
- 24/7 Support
Sitelinks
- Pricing
- Book Demo
- Case Studies
- Compare Plans
For large accounts, producing these manually at scale is difficult.
If AI can create 75% usable assets instantly, that’s a major win.
Where Human Copy Still Wins
AI often struggles most with:
- Brand positioning
- Emotional persuasion
- Unique value propositions
- Sophisticated B2B messaging
- Conversion-focused RSA headline sets
In these areas, expert human copywriters still outperform automation.
Use AI to support creative work, not fully replace it.
Common Mistakes to Avoid
Overloading Rules
Too many vague restrictions confuse systems.
Never Reviewing Outputs
Even good automation needs QA.
Only Negative Rules
Tell AI what to do, not just what not to do.
Ignoring Performance Data
Balance brand judgment with metrics.
Treating It as Set-and-Forget
Markets change. Offers change. Guidelines should evolve, too.
Why This Effort Pays Off
Ads are the only part of the account prospects actually see.
Users do not see:
- Your bids
- Match types
- Negative keywords
- Campaign structure
They see your message.
That means copy quality directly affects:
- CTR
- Conversion rate
- Lead quality
- Brand perception
- Efficiency
A few hours spent building strong guidelines can improve performance across campaigns for months.
Final Thoughts
AI Max can be highly effective when paired with strong guardrails.
The smartest advertisers will not choose between humans and AI.
They will combine:
- Human strategy
- AI speed
- Clear rules
- Ongoing optimisation
That is how you turn automated ad creation into a genuine competitive advantage.
Need a fresh perspective? Let’s talk.
At 360 OM, we specialise in helping businesses take their marketing efforts to the next level. Our team stays on top of industry trends, uses data-informed decisions to maximise your ROI, and provides full transparency through comprehensive reports.
.png)
