Notes

The Long Arc of Tenacity: Nancy Wexler’s Journey

Most people underestimate time. We think of effort as something you can measure in hours, days, maybe a few years at best. We live in startup time—sprints, ship cycles, quarterly OKRs. But there’s another kind of time, one that runs on decades. That’s the time Nancy Wexler lived in. Wexler’s story begins not in a…

My Life’s Priorities

I read this quote a long time ago and it has stayed with me ever since: ā€œSomeone once told me the definition of Hell: The last day you have on earth, the person you became will meet the person you could have become.ā€ – Anonymous This idea sparked my lifelong pursuit of unlocking not only…

Foundations of the A2A Economy: AI Agent Interoperability Protocols

With the rise of Anthropic’s MCP (& quickly becoming one of the emerging open standards) and Google’s recent announcement of the Agent2Agent Protocol (A2A), it’s clear the technology world is racing full-speed toward laying the foundations of the A2A economy. What I initially thought would take years is now unfolding in mere months — a…

AI-Default Organizations

Tobi Lütke recently shared Shopify’s internal memo setting the baseline expectation for AI usage across their company. If you think back a few decades, organizations began expecting employees to use desktop computers by default. Then it was Microsoft Office. Then it was the internet. Employees who adopted these tools early were seen as far more…

Evolutionary Prompting: Using modular prompts to improve AI agent performance

There’s a lot to be said about efficiency—whether you’re writing code or crafting prompts for an AI. The basic idea is simple: if you can break something complicated into reusable, modifiable parts, you can build better systems faster. In AI, that means rethinking how we write prompts for LLMs and AI agents. Modular Prompts: The…

The Three Stages of the A2A Economy

In just a few years, AI—specifically OpenAI—has transformed what was once an interesting toy into a force that’s reshaping various industries and jobs in a non-linear way. Enter the new economic paradigm, known as the agent-to-agent (A2A) economy, where AI-driven agents from different organizations—or even between businesses and consumers—collaborate, negotiate, and transact autonomously. At the…

Rise of the A2A economy: How AI agent-to-agent interactions will reshape the world

At Sendbird, we’ve been actively working with companies across the globe that are considering the adoption of conversational AI to enhance their customer service. During this process, we’ve encountered many forward-looking enterprises eager to accelerate their adoption of AI agents—not just for customer service, but also to drive transactions and revenue growth. This got us…

Annual Operating Rhythms and Time Budgeting

As I progressed through life, I became increasingly aware of two major constraints on productivity: time and energy. While energy depends on the health of both body and mind, today I’ll focus on time. By the time you’re 10–20 years into your career, you (hopefully) have a solid grasp of managing your schedule. I recommend…

My Camera Bag Setup (FujiFilm X100VI)

Last update: 2025-01-01 Perfect camera bag setup didn’t exi… I quietly enjoy capturing photos of the people I meet, the places I visit, and the things that inspire me—like architecture, engineering, and art. To simplify traveling and avoid the complexity of lugging around a full camera kit, I’ve switched to using compact fixed-lens cameras. The…

Happy New Year 2025!

Happy New Year 2025 everyone! šŸŒ… I hope you’re all starting the year with a lot of hope, renewed energy, and big dreams. I began my morning with a run, followed by a short trip to the shores to take part in my annual ritual of planning for the year ahead. The day greeted me…

Health Supplements Stack

Inspired by Lifespan (David A. Sinclair), Bryan Johnson, and a few others, below is my current supplements stack as of today (2024-09-17). I will need to track my blood work and other biomarkers regularly over a period of time to assess the efficacy of the regimen, but for now, I am proceeding based on some…

How to Calculate Terminal ARR for Startups Using a Simple Formula

Startup founders often wonder (and fear) when their growth will slow down and eventually plateau. Especially in the early days of achieving product-market fit, the hustle and rapid growth often lead founders to overlook certain crucial metrics that ultimately determine the growth limit of the company. In biology and engineering, there is a concept called…

Abstractions and Why Details Still Matter

Today, I came across an interview with Jerry Seinfield that left an impression on me. One paragraph in particular stood out: If you’re efficient, you’re doing it the wrong way. The right way is the hard way. The show was successful because I micromanaged it—every word, every line, every take, every edit, every casting. That’s…

Performance Review Template

As you scale your startup beyond 20 people, you will start implementing a formal performance review process. The cadence could be once a quarter, once every 6 months, or sometimes, once a year. The rule of thumb is that if your direct report is deeply surprised by the content in your feedback, it means you…

The Level 5 Ownership

Leaders are often called upon to resolve conflicts and problems. During this process, we all experience varying degrees of ownership from the people involved. The level of ownership significantly affects how we problem-solve with these individuals and the effectiveness of our efforts. However, ownership is a concept that is often talked about but less understood.…

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ABOUT Positive Tenacity

These are my notes from building and investing in startups. I’m John S. Kim, Co-Founder/CEO of Sendbird, and General Partner at Valon Capital/ASQ. Learn more here.

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