How to Evaluate GEO Agencies Through Reviews and Differentiators

When you look at the reviews of GEO agency, you can see that the difference in performance is quite large even with the same period and similar budget. There is one reason why SUMMITFEED experienced it firsthand while operating clients in various industries. The gap between agencies that understand and design how AI search engines construct answers and agencies that just take the approach of ‘I can write a lot of good articles’ is bigger than I thought.

ChatGPT, Gemini, and Perplexity each have different ways of generating answers. Perplexity is closer to a structure that directly cites real-time web crawling results, while ChatGPT combines learning data, plug-ins, and search functions. Gemini is deeply linked to Google index. If you produce content in a single format without knowing the difference, it may end up being cited only on certain platforms and not caught on others.

Ultimately, the performance gap between agencies that design their Content structure differently according to the response algorithm for each platform and those that do not widens over time. Although the first 2 to 3 months may seem similar, after about 6 months, the citation frequency trend often diverges significantly.

If, after entrusting it to an agency, you ask, ‘Is everything going well?’ and the answer you get is ‘I’m working hard,’ that may be a sign that you don’t have the tools to measure performance. The existing SEO was able to immediately check the ranking and number of clicks using Google Search Console or Naver Webmaster Tool, but GEO does not yet have such an official tool, so whether the agency has its own tracking system is an important decision point.

Our real-time citation rate dashboard tracks how many times our client's content has been cited in ChatGPT·Gemini·Perplexity answers each week. We adjust the direction of the next content by looking at what content was uploaded in the week when the numbers went up and, conversely, what variables were present when citations decreased. It is a structure that is not operated by intuition, but rather is guided by data.

With a tracking tool like this, clients can objectively verify agency performance. Instead of saying, ‘We published 10 pieces of content this month,’ the conversation changes to say, ‘The number of citations to Perplexity this month has increased by this much compared to the previous month.’ It becomes much clearer when deciding whether to extend a contract.

Schema markup is a code that clearly tells the AI ​​search engine whether ‘this content is an FAQ, a review, or medical information.’ While humans understand text through context, AI processes structured signals more quickly and accurately. So, pages where Schema is properly applied have a higher probability of being cited first in AI answers.

In fact, if you compare the version with and without FAQ Schema, even if it is the same content, there are cases where there is a difference in citation frequency between Perplexity and Gemini. In particular, when applying FAQ Schema to content in the form of questions and answers, a pattern is quite often observed where AI extracts the Q&A as it is and inserts it into the answer.

When choosing an agency, it is best to ask directly whether Schema applies. If you ask ‘Do you apply structured data?’ and the response is ‘What is that?’, the agency is likely more familiar with traditional SEO methods than AI search optimization.

In regulated industries such as hospitals, clinics, law firms, and financial companies, there are actually cases where uploading content incorrectly leads to detection by the Ministry of Food and Drug Safety or the Financial Supervisory Service. In particular, if you aggressively accumulate content for AI search optimization, a situation may arise where articles written by agencies that do not know the medical advertising law or financial advertising regulations can become problematic.

We operate a process of reviewing content in the medical, legal, and financial industries according to industry-specific regulations before publishing. It specifically points out things like, ‘This expression may be subject to Article 56 of the Medical Advertising Act’ and ‘This phrase does not meet the review standards for financial advertising.’ From the client's perspective, it not only ensures the effectiveness of the content but also blocks risks at the source, so the response is particularly good in regulated industries.

When choosing an agency, rather than asking, ‘Do you have experience in a regulated industry?’, it is more accurate to ask, ‘Do you have a legal risk review process in place before issuance?’ Even if you have experience, mistakes can be repeated if there is no systematic inspection system.

GEO When looking at agency reviews, it is actually difficult to judge results-oriented reviews such as ‘sales have increased’ or ‘inquiries have increased’. I can't tell whether the increase in sales is due to AI search optimization, seasonal factors, or other marketing channels.

Highly trustworthy reviews contain specific indicators of change. For example, if there is content such as ‘Perplexity began to be cited with a specific keyword’, ‘ChatGPT mentioned our brand first instead of our competitors’, or ‘Content that other agencies could not do due to medical advertising risks was reviewed and published’, this is a signal that the agency has actual operational experience.

Conversely, there are also review patterns to watch out for. If the review is focused on output, such as ‘You did a great job on the blog post,’ or if it is a review that only received reports throughout the contract period and did not confirm actual changes in AI citations, the agency may have a weak performance tracking system.

AI search and Naver search have different algorithms, so strategies must also be different. For Naver, factors such as keyword density, dwell time, and blog index are important, while for AI search, the degree of structure of content, citable answer format, and Schema signals are more important. If you entrust the two channels to different agencies, there may be problems with conflicting strategies or overlapping content.

By operating with an integrated strategy, one piece of content can be designed to be effective in two channels simultaneously. If an article posted on the Naver blog contains structured data, the likelihood of being cited in AI searches increases, and conversely, a structure written with the goal of AI citations also attracts Naver search traffic. In many cases, overall search traffic efficiency is higher than when managing channels separately.

However, even if an agency promotes integrated management, it is a good idea to make sure that they actually have dedicated staff to handle both channels. There are cases where one team says they are doing everything, but in reality they only run the Naver blog and GEO is just the name.