Key takeaways
- The 10 expert skills of an SEO agency can all be tested before you sign: bring one real URL, one audit finding and one page of your own to the sales call.
- Ask them to explain the difference between the indexed result and the live test in URL Inspection. People who work from Google’s data answer in a sentence.
- Ask how long redirects should stay after a migration. Google says generally at least a year.
- Ask whether valid structured data guarantees rich results. Google says it doesn’t, and an expert will say so.
- Score every answer pass, partial or fail. A polished deck with three fails is a weaker agency than a plain one with none.
Every agency pitch lists skills. The list rarely tells you who can do the work. This article sets out the 10 expert skills of an SEO agency that I think matter most, and for each one a practical test you can run in a sales call, using your own site and Google’s own documentation as the answer key.
I have worked in SEO and digital marketing for more than 16 years, on both sides of that call: pitching, and helping clients judge other pitches. The tests below are the ones that separate people who do the work from people who sell it. None of them needs technical knowledge from you. They need one URL, one finding and one page.
If you want a list of questions about contracts, access and billing, I have covered those in 21 questions to ask SEO consultants. This one is about ability.
The 10 expert skills of an SEO agency at a glance
| # | Skill | The test in the call | Pass sounds like |
|---|---|---|---|
| 1 | Crawling and indexing diagnosis | “This URL isn’t in Google. How would you find out why?” | Starts with URL Inspection and explains what it shows |
| 2 | Prioritisation | “Here are three findings. Which first?” | Ranks by impact on pages that earn money |
| 3 | Developer-ready instructions | “Show me a ticket you’d send our developer.” | Problem, fix, how to test, in plain words |
| 4 | Migrations and redirects | “How long do redirects stay after a move?” | Generally at least a year, with a full URL map |
| 5 | Structured data | “Does valid markup guarantee rich results?” | No, and markup must match visible content |
| 6 | Search intent and keyword value | “Which of these five queries is worth most to us?” | Asks about your margins before answering |
| 7 | Content assessment | “What’s wrong with this page of ours?” | Specific edits, not “add more keywords” |
| 8 | Link building within the rules | “Do you ever pay for links?” | Explains qualified paid links and why |
| 9 | Measurement | “What will you report, and from where?” | Search Console and analytics, tied to goals |
| 10 | Reading the results page | “What does our main query’s results page look like?” | Has looked, including AI features |
Technical skills (1 to 5)
These are where a professional search engine optimization agency earns its fee, because mistakes here can take pages out of Google altogether.
1. Crawling and indexing diagnosis
Test: bring a URL that isn’t indexed and ask how they would find out why.
The answer should start with the URL Inspection tool in Search Console. Push one step further: ask what the difference is between the indexed result and the live test. Google’s help page says the indexed view “is not a live test”, while the live test means “the tool fetches and examines the URL in real time.” It also says a passing live test “only confirms if Google-InspectionTool can access your page for indexing”, and that requesting indexing “does not guarantee that the page will appear in the Google Index.”
Fail: “We’ll just submit it to Google.” That is a notification, not a diagnosis.
2. Prioritisation
Test: hand over three findings from any audit you have, including a free tool’s, and ask which they would fix first and why.
A good agency asks which pages bring you enquiries or sales before answering. A weak one picks the finding with the scariest label. Audit tools produce long lists. Turning a list into an order of work is the skill you pay for.
3. Developer-ready instructions
Test: ask to see a ticket they have sent a developer (with the client’s details removed).
You want the problem, the affected URLs, the fix, and how to check it worked. If the sample is a screenshot of an audit tool with “fix these” written on it, your developer will spend hours working out what is meant. This is the core of an expert technical SEO agency for marketers: the marketer can pass the work on without translating it.
An agency that can’t write a clear ticket will bill you twice: once for the advice, and again for explaining it.
4. Migrations and redirects
Test: ask what they need before a redesign or domain change, and how long redirects should stay in place.
Google’s site move guide says “It’s important to map your old site’s URLs to the URLs for the new site”, to “Use server side permanent redirects if technically possible”, and to “Keep the redirects for as long as possible, generally at least 1 year.” It also warns that visibility “may fluctuate temporarily during the move.” A good answer mentions the map, the redirect type, the time frame and the warning. I set out the full scope in what drives the cost of migration SEO.
5. Structured data
Test: ask whether valid markup guarantees rich results, and whether it’s fine to mark up something the page doesn’t show.
Google’s structured data guidelines say Google “does not guarantee that your structured data will show up in search results”, and “Don’t mark up content that is not visible to readers of the page.” A structured data problem “can result in a manual action”. The right answer is two noes and a reason.
Content and research skills (6 and 7)
6. Search intent and keyword value
Test: give them five queries you care about and ask which is worth most to your business.
A good agency doesn’t answer straight away. It asks what you sell, what a customer is worth and which pages convert. Search volume alone is the weakest way to pick targets. The best answer weighs volume, the price of a click, where you rank now and what a visit is worth to you.
7. Content assessment
Test: send one of your important pages in advance and ask what they would change.
Google’s guide to creating helpful content offers questions any expert should know, such as “Does the content provide original information, reporting, research, or analysis?” and “Is this the sort of page you’d want to bookmark, share with a friend, or recommend?” It also asks who made the content, how and why, and calls “why” the most important.
Pass: specific edits, such as a missing answer, a vague claim to back up, an author to name. Fail: “Add more keywords and make it longer.”
Links, measurement and the results page (8 to 10)
8. Link building within the rules
Test: ask, plainly, whether they ever pay for links.
Google’s spam policies define link spam as “creating links to or from a site primarily for the purpose of manipulating search rankings”, including “Buying or selling links for ranking purposes” and “Excessive link exchanges”. The same page says paid links are not a violation “as long as they are qualified” with rel=”nofollow” or rel=”sponsored”.
An honest agency explains that line: sponsored placements can be fine for exposure when qualified, but they are not a ranking tactic. It should also show you every link it builds. Our own strategic link building works that way, and so should anyone you hire.
9. Measurement
Test: ask what the monthly report will contain and where each number comes from.
You want Search Console for clicks, impressions and queries, your analytics for conversions, and a clear link between the two and your goals. Be careful with reports built mainly on traffic charts and “visibility” scores from tools you can’t check. Ask: “If a number goes down, will you tell me why?”
10. Reading the results page
Test: ask what the results page looks like today for your most important query.
The right answer comes from someone who has looked: which competitors appear, whether there is a map pack, shopping results, videos or an AI Overview, and what that means for clicks. For informational queries this now includes AI features, and I set out what to ask about those in questions for an SEO expert for Google AI search. A good agency plans around the page as it is, not as it was when the pitch template was written.
How to run the tests on one sales call
You don’t need ten separate meetings. Send a short pack before the call so the agency can prepare. Preparation is fair: you are testing judgement, not memory.
Send before the call
- One URL that isn’t indexed, or that you think underperforms
- Three findings from any audit you have, even a free one
- One important page you’d like their opinion on
- Five queries you’d like to win
- A sentence on what a new customer is worth to you
During the call, ask the ten questions in the table and write down each answer as you hear it. Don’t help. If they ask clarifying questions, that’s a good sign, not a weakness.
How to score the answers
After the call, give each skill one of three marks.
| Mark | What it means |
|---|---|
| Pass | A specific answer that matches Google’s documentation or your own data |
| Partial | Right direction, but vague, or they promised to come back with detail |
| Fail | Wrong, evasive, or a sales line instead of an answer |
Compare agencies on fails first. One fail on skill 1, 4 or 8 is serious: those are the skills where a mistake removes pages, loses a migration’s traffic or attracts a penalty. A fail on skill 6 or 9 is a warning about how they’ll spend your budget.
Be fair in the test
No agency knows your business on the first call. “I’d need to see your Search Console to answer properly” is a good answer to most of these, as long as they tell you what they’d look for. Mark it partial, not fail.
Where I stand on these ten
I’d expect to be tested on all ten myself. I charge by the hour, with no fixed packages, so you only pay for the skills your site needs. Technical SEO is one of my core specialisms, and my background is set out on my profile page. You can read how I work on why onwardSEO, then run the tests on me too.
FAQ
What makes a professional search engine optimization agency?
The ability to explain its work against Google’s documentation and your own data. A professional agency diagnoses before it prescribes, writes instructions your team can act on, stays within Google’s spam policies and reports from sources you can check yourself.
What should an expert technical SEO agency for marketers deliver?
Clear, prioritised instructions that a marketer can hand to a developer without translating them: the problem, the affected URLs, the fix and how to test it. It should also explain the business reason for each fix in plain language.
Do I need an agency with all 10 skills?
Not always. A small local business might rely mostly on skills 6, 7 and 10, while a large catalogue or a migration leans on 1 to 5. Decide which skills your site needs most, then weight the score towards them.
Can I test an SEO agency without technical knowledge?
Yes. Most of the tests above have answers you can check against Google’s own pages, which are linked in this article. You are listening for specifics, honesty about limits and no guarantees.
If you'd like to run these ten tests on me with your own site in front of us, book a call and bring your URL, your findings and your page.
Eugen Platon · SEO consultant with 16+ years in SEO and digital marketing · free 10-minute first call
Eugen Platon
Latest posts by Eugen Platon (see all)
- How Much Does an SEO Consultant Cost? Pricing Models Explained - November 8, 2026
- Technical SEO Consultants vs Agency Services: Which Do You Need? - November 8, 2026
- White Label SEO Link Building: How Agencies Resell Links Without Risking Clients - November 8, 2026
- SEO Content Creation Services: What You Should Get for the Money - November 8, 2026