Here at Mercari, most employees have already started using AI in their daily work as we move toward becoming AI-Native. However, not everyone may be on the same page about what exactly the “AI-Native” company and talent that Mercari is aiming for look like.

So how are Mercari’s AI-Native employees utilizing AI? For this volume of our series, we spoke with @kawaty from Mercari’s B2C business, which operates services like Mercari Shops, our e-commerce platform for businesses. He is responsible for sales operations and sales planning. What stood out most was how naturally—and enthusiastically—he’s woven AI into his work. In this article, we delve into his journey with AI and where he is today.

What does it mean to be AI-Native? How will the job of sales change? In an age where anyone can work with data, what role still needs to be fulfilled by humans? Through this passionate conversation, we gain the hints to unraveling these questions.

AI and sales: I can achieve so much, and I’m not an engineer!

@Yurino:  I heard you’re making great use of AI in the sales domain. What led you to start using AI?

@kawaty:  It all started when I participated in a study session on generative AI held within the company around summer or fall of 2024. That was where I learned the basics of how generative AI could create text and generate ideas. I began playing with AI by casually asking Gemini questions. As I gradually interacted with it more, I started to think that maybe I could change the way I worked.

At the time, part of my work involved looking up the corporate numbers of businesses one by one on the National Tax Agency website, which took a lot of effort. So I worked together with AI to develop a system that used a corporate number API to retrieve the information semi-automatically in a spreadsheet. Ultimately, I was able to connect that system to Google Apps Script, marking my first major practical application of AI.

@Yurino:  And that’s when your usage of AI took off, right?

@kawaty:  Yes. I felt like a child finally executing their first successful pull-over on the horizontal bars. Realizing that I too could develop tools gave me the confidence to keep going, and my head was filled with endless possibilities. I worked with AI whenever I came up with a new idea.

@Yurino:  How are you using AI right now for sales planning?

@kawaty:  Sales planning involves building data-driven systems that support the members who work in sales and marketing. We analyze trends in key metrics and how marketing and sales expenses are used, and make connections between all the numbers. For this, I mainly use AI for three purposes:

• Brainstorming ideas
• Writing SQL
• Operating spreadsheets

I use Cursor for writing SQL. You can achieve quite a bit with instructions in natural language. I used to have to spend time figuring out how to write SQL for the information I wanted to retrieve, and troubleshooting errors also took time. Now, I get things done much faster by interacting with AI using natural language. The amount of thinking I can do within the same amount of time has changed significantly, and I feel like the difference will only continue to grow over time.

@Yurino:  It sounds like the pace of work will change dramatically.

@kawaty:  Yes, it’s already changed a lot. Recently, I was especially impressed by how you can use Claude Code with spreadsheets. For example, in a table with over 100 rows, I can simply tell the model, “Add a year-over-year comparison column here,” and it adds the column while keeping all the formulas intact.

Just by roughly explaining what I want to do, the model will access the data and return the desired results. This has sped up my more more than anything else.

@Yurino:  I also understand you have some unique ways of using AI; I’d love to hear more about that too.

Mastering AI as if agents were generals

@kawaty:  I love the manga Kingdom, so I like to use Claude Code’s sub-agents as if they were generals. My position is equivalent to that of the “Great King,” and I give instructions to my right-hand person and multiple generals.

For example, if I say something like, “I want to know whether the B2C business’s February sales were a temporary fluctuation or the result of a structural change,” the tasks are divided among multiple agents (generals), who analyze things in parallel. Each one looks at the data according to its role, and in the end they return an integrated report.

@Yurino:  It’s as if the analysis work you used to do yourself is now divided among a team of members with different specialties.

@kawaty:  Exactly. I give each general a dedicated role, for instance:

• One that oversees the entire process
• One that breaks down the analysis and gives instructions
• One that points out oversights in the other agents’ thinking

I design many specific roles. By doing this, I can examine things from multiple perspectives instead of risk becoming biased toward a single viewpoint. As a result, the output—including even the SQL used—is returned in a certain format.

@Yurino:  How do you create those generals?

@kawaty:  For each general, I build a character by putting detailed prompts in place, including their verbal habits, thinking style, and even philosophies learned from past “battles.” I also incorporate Mercari’s employee grade system, and I set my right-hand person and generals at grades higher than my own. So, it’s like delegating work to people more capable than me. (laughs)

I also establish rules, like:

• Report based on facts
• Say “I don’t know” when you don’t know

These rules are set as “military laws” that the generals must follow.

@Yurino:  I can really tell how much you enjoy using AI from the world you’ve built!

@kawaty:  Building this setup has naturally made me want to interact with AI even more. By adding an element of play and creativity, I can feel the range of ways I use AI in my work expanding significantly as a result.

Beyond data, salespeople will provide “the final push”

@Yurino:  What do you think is important for spreading AI usage within a team?

@kawaty:  I believe the condition for spreading AI adoption is to create a state in which the people around you are using it. When someone you talk with regularly is using AI, you naturally get influenced. It’s important to create that environment.

On the other hand, the hardest part is the initial setup. As mentioned in @Kyohei’s article, it’s important to try starting from practical applications that people can use immediately, and avoid starting from things that are too difficult. However, a minimal amount of setup is unavoidable. That’s why I think it’s important to work together to take that first step. I’ve shared how I created systems with AI with my team as well, and I want to be someone they feel comfortable casually reaching out to with questions.

@Yurino:  What challenges would you like to tackle with AI next?

@kawaty:  I want to make it easier for sellers on Mercari Shops to grow their sales using AI. For example, if they enter something like, “I want to achieve this sales target this month,” or “This is roughly the budget I can use,” AI would suggest the optimal promotions and even the best timing for limited-time sales, and then allow them to execute those actions directly. Right now, Mercari’s sales members support that process, but in the future, sellers would ideally be able to consult with AI directly from the admin dashboard and run promotions from there.

@Yurino:  What roles do you think will remain in sales when AI can handle everything from analysis to execution?

@kawaty:  I think salespeople will gradually become people who provide the “final push” in making decisions. The core of our role—being a partner in improving the client’s business together—will not change, but within that role, we will shift more toward being a trusted presence.

With AI, anyone will easily be able to generate the information needed for decision-making, such as ROI and campaign effectiveness, and strategies themselves will accumulate as assets. However, the more information there is, the more choices there are—and paradoxically, deciding which option to choose becomes harder. That’s why I think what ultimately matters is whether people feel like we are someone they can consult.

@Yurino:  It really does feel like the value of information itself will decline.

@kawaty:  Yes. That’s why I think it’s important to be genuine and share not only favorable information about our company but also issues and context, engaging with clients in a way that allows them to feel that we’re invested. I believe the accumulation of such interactions is how trust is built. Even if AI presents us with a plan, there will still be moments when we seek human judgment and ask another person what they think. That’s why I think the future value of salespeople will be in whether they can become the person others rely on in the end.

The data is there, but people still want a reliable person to provide that final push. Even if they already know the answer themselves, they still want someone to tell them, “Go for it.” I believe that’s the role that sales will gradually fill.

@Yurino:  What does being AI-Native mean to you?

@kawaty:  That AI is the first thing that comes to mind. Put simply, it means that when faced with a challenge or question, the natural choice is to ask or delegate to AI. I’m part of the generation that’s often called “internet-native,” and I think being “native” to something means it’s unconsciously your first choice.

For example, just as you might choose LINE or Instagram DMs instead of email to get in touch, when you have something you want to do or consider, relying on AI rather than conducting a search becomes your default choice.

@Yurino:  So the key is whether AI naturally comes to mind as your first choice.

@kawaty:  Of course, you’d need to start from taking an interest in AI and actually trying it out, and even if your first instinct is still to search for information in the beginning, I believe there will come a moment when AI becomes your natural first choice. I am still in the process myself (laughs).

@Yurino:  Lastly, do you have a message for people who want to become better at using AI?

@kawaty:  I don’t think you need to master it perfectly from the start. If you keep asking AI about things you’re interested in, you will naturally get used to it over time. There’s no single correct way to get over the initial hurdle, but I think that deciding to try using AI for whatever task you have at hand is already a step forward. Honestly, there’s also a part of me that thinks I look kind of cool using Cursor or Claude Code (laughs). Your motivation for trying AI can simply be small things like that!

@Yurino:  I’m actually using Cursor to write the first draft of the articles in this series, and while editing, I sometimes find myself thinking, “Hey, I’m kind of cool.” (laughs)

@kawaty:  Right? When I split screens and display my work on a side monitor, it makes me feel like an engineer. I think it’s important to enjoy the process and keep at it, even if that means embracing excitement over what feels “cool.” I encourage everyone to find their own motivation to give AI a try!

@Yurino:  Thanks, @kawaty!

@Yurino and @kawaty as generals wielding AI-generated weapons!