How I Pick AI Subscriptions by Budget and Role
Before you compare prices, decide whether you code for work. The same budget buys a completely different stack for builders and non-builders.
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AI Platforms & Tools
Anthropic, OpenAI, Google, and other AI platform deep dives.
101 posts
Starting Codex? Open This Guide First
I keep a living Codex Vible for install, settings, App vs Web, and how it differs from ChatGPT, because the product ships updates faster than most people can relearn it.
Builders Are Already Patching Codex for Performance and Quota
Two structural issues in Codex defaults cut reasoning short and explode agent trees. Here is what I measured and the config.toml changes that fixed both.
Claude Code Was Billing Tens of Thousands of Hidden Tokens Per Turn
Matt Pocock's method: run /context, rank tool payloads, then trim settings.json with disable flags and bare tool-name denies so unused definitions stop riding every message.
Sending Code as Images Cut Token Cost About 60%
Dense pixel fonts pack ~40k characters into one Anthropic image bill. pxpipe production logs show ~59% savings, with caveats: Fable 5 only, and keep IDs as text.
How I Stretch Fable 5 Under Tight Rate Limits
When Fable 5 is available but capped, keep effort at high, reserve it for judgment, and push bulk work to Codex or Sonnet. Write the routing into CLAUDE.md first.
An Agent Kit for App in Toss Miniapps: Rules Before Vibes
appintoss-kit layers AGENTS.md, guides, skills, hooks, and review agents so Codex/Claude/Cursor stop missing policy, Korean UX, design rules, and store metadata.
Four Small Tools I Built to Make Daily Codex Less Annoying
A ChatGPT→Codex handoff bridge, multi-account config sharing via symlinks, a menu-bar status app, and an imagegen API with provider fallback.
My OpenAI Founder Day Talk: Codex for Non-Developers
I shared the deck and seven solo-builder workflows from the only solo-builder session I ran at Founder Day 2026 — including the fact Codex built the slides.
Stop Installing Skills Globally. Symlink Them Per Project
A full global skills library loads junk into every session. Keep one warehouse of clones and symlink only what each repo needs.
Twelve Codex Tricks Power Users Quietly Share
ChatGPT-as-MCP planning, multi-account gateways, Excalidraw intent, imagegen fan-out, remote handoff, grill-me PRDs, kanban agents, and multi-tool control.
Closing Note After OpenAI Founder Day Seoul 2026
The day reinforced that solo builders can hold a room with executives — if the workflows are real and the deck is honest.
OpenAI Founder Day Seoul. What a Day.
A short field note from a packed room: builders, executives, and the odd feeling of being the only solo operator on the agenda.
Karpathy’s LLM Wiki Idea Just Got a Standard-Shaped Push
When knowledge for agents is formatted like a product surface, wikis stop being human-only documentation.
The “Senior Who Turns 50 Lines Into One” Is Now an Agent
Encode review taste as rules and examples, then let an agent apply the same compressions a strong reviewer would.
A Prompt That Forces Consulting-Style Slide Structure
Pick one of six structures, lock design tokens, run a 3-second test — stop getting pretty bullet dumps with no “so what.”
22 Agentic Engineering Practices I Actually Use Daily
No IDE heroics: plan.md, voice, cmux tabs, remote control, skip-permissions discipline, research-before-plan, and resting before AI psychosis.
사용자의 반복 작업을 스스로 skill 로 만드는 프롬프트가 큰 화제입니다
Blog version of a 2026-05-30 LinkedIn note — same claims, cleaned structure for reading.
"진짜" AI 네이티브 조직을 "현실적으로" 구축하려면 어떻게 해야할까요
Blog version of a 2026-05-29 LinkedIn note — same claims, cleaned structure for reading.
OpenAI Founder Day
Blog version of a 2026-05-26 LinkedIn note — same claims, cleaned structure for reading.
MCP 프로토콜이 7월 28일에 완전히 바뀝니다
Blog version of a 2026-05-26 LinkedIn note — same claims, cleaned structure for reading.
핸드폰으로 에이전트를 원격 제어하는 방법을 총정리했습니다
Blog version of a 2026-05-25 LinkedIn note — same claims, cleaned structure for reading.
디자이너라면 한 번 읽어보시면 좋을 것 같아요
Blog version of a 2026-05-25 LinkedIn note — same claims, cleaned structure for reading.
에이전틱 코딩으로 생산성을 올리고 싶다면, 이 5가지 개념부터 잡아야 합니다
Blog version of a 2026-05-23 LinkedIn note — same claims, cleaned structure for reading.
FDE Forward Deployed Engineer
Blog version of a 2026-05-21 LinkedIn note — same claims, cleaned structure for reading.
AI 에게 맥락을 제대로 주고 싶다면, 관계를 Graph 로 만드세요
Blog version of a 2026-05-21 LinkedIn note — same claims, cleaned structure for reading.
Codex 제대로 쓰는 법, 9가지 요소로 정리한 이 글 하나면 충분합니다
Blog version of a 2026-05-21 LinkedIn note — same claims, cleaned structure for reading.
대한민국 디지털 정부 디자인 시스템 KRDS, AI Skill 이 없길래 직접 만들었습니다
Blog version of a 2026-05-19 LinkedIn note — same claims, cleaned structure for reading.
구글 I/O 2026 은 충격적인 업데이트의 연속이었습니다
Blog version of a 2026-05-19 LinkedIn note — same claims, cleaned structure for reading.
4B 모델 87점 vs 14B 모델 75점. 차이는 하네스입니다
Blog version of a 2026-05-19 LinkedIn note — same claims, cleaned structure for reading.
Claude Code Codex
Blog version of a 2026-05-16 LinkedIn note — same claims, cleaned structure for reading.
Codex 도 핸드폰 안으로 들어왔습니다
Blog version of a 2026-05-15 LinkedIn note — same claims, cleaned structure for reading.
Codex 로 PPT 예쁘게 만들기
Blog version of a 2026-05-13 LinkedIn note — same claims, cleaned structure for reading.
요즘 한국 AI 씬에서 가장 진솔하면서도 유익한 콘텐츠를 만든다고 생각하는 두 분과 각각 커피챗을 가졌다. 한 분은 "까칠한 AI"라는 유튜브를 운영하시는 SpaceY 황현태 대표
Blog version of a 2026-05-12 LinkedIn note — same claims, cleaned structure for reading.
오늘부터 하루에 하나씩 저의 업무 전용 AI 도구를 무료로 공개합니다.
Blog version of a 2026-05-12 LinkedIn note — same claims, cleaned structure for reading.
제가 좋아하는 AI 디자인 관련 레퍼런스를 모두 모았습니다
Blog version of a 2026-05-10 LinkedIn note — same claims, cleaned structure for reading.
만약 토스 시니어 디자이너가 Codex 의 UI 를 리뷰한다면?
Blog version of a 2026-05-08 LinkedIn note — same claims, cleaned structure for reading.
/goal 을 더 잘 쓰고 싶다면, 메타 프롬프팅을 활용하세요
Blog version of a 2026-05-05 LinkedIn note — same claims, cleaned structure for reading.
디자인 킬러 DESIGN.md 를 가장 잘 사용하는 워크플로우를 정리했습니다.
Blog version of a 2026-05-05 LinkedIn note — same claims, cleaned structure for reading.
Codex 가 무거워지기 시작했다면 이 글을 한 번 보세요.
Blog version of a 2026-05-04 LinkedIn note — same claims, cleaned structure for reading.
AI를 잘 쓰는 사람과 못 쓰는 사람의 차이, 저는 읽는 능력 하나라고 봅니다
Blog version of a 2026-05-02 LinkedIn note — same claims, cleaned structure for reading.
OpenAI 가 직접 공개한 현 시점 최고 모델 GPT-5.5 프롬프트 작성법.
Blog version of a 2026-04-30 LinkedIn note — same claims, cleaned structure for reading.
한국어로 Claude를 쓰면 영어보다 2.59배 비쌉니다
Blog version of a 2026-04-29 LinkedIn note — same claims, cleaned structure for reading.
Anthropic 이 클로드 코드의 문제를 공식적으로 인정했습니다
Blog version of a 2026-04-23 LinkedIn note — same claims, cleaned structure for reading.
보고서, 이제 바로 슬라이드가 됩니다.
Blog version of a 2026-04-23 LinkedIn note — same claims, cleaned structure for reading.
사람들은 4년 동안 AI 이미지를 냉소했습니다.
Blog version of a 2026-04-22 LinkedIn note — same claims, cleaned structure for reading.
슬라이드, 이제 바로 영상이 됩니다.
Blog version of a 2026-04-21 LinkedIn note — same claims, cleaned structure for reading.
Codex computer use
Blog version of a 2026-04-19 LinkedIn note — same claims, cleaned structure for reading.
AI 토큰 소모를 60% 이상 절약하는 무료 방법 10가지를 모았습니다
Blog version of a 2026-04-18 LinkedIn note — same claims, cleaned structure for reading.
병렬 에이전트를 잘 관리하려면 격리하고 기록하고 합치는 구조가 먼저입니다
Blog version of a 2026-04-13 LinkedIn note — same claims, cleaned structure for reading.
프론티어 기업은 AI 도입에 전략이 없었습니다
Blog version of a 2026-04-10 LinkedIn note — same claims, cleaned structure for reading.
오늘부터 Codex Pro 플랜 사용자는 2배 이벤트를 다시 시작합니다
Blog version of a 2026-04-10 LinkedIn note — same claims, cleaned structure for reading.
Codex Is Not Helpless at Design — Your Spec Might Be
Weak UI usually means weak visual language in the prompt.
Gemini NotebookLM
Blog version of a 2026-04-09 LinkedIn note — same claims, cleaned structure for reading.
공식적으로 Claude 의 뇌와 손이 분리되기 시작했습니다
Blog version of a 2026-04-09 LinkedIn note — same claims, cleaned structure for reading.
AI 콘텐츠 수집 아직도 수동으로 하고 계시면, 이 5개부터 당장 깔아보세요
Blog version of a 2026-04-08 LinkedIn note — same claims, cleaned structure for reading.
4월 들어서 에이전트 개발에 완전히 올인하고 있습니다.
Blog version of a 2026-04-06 LinkedIn note — same claims, cleaned structure for reading.
Why Your Codex Config Isn't Working: The .codex/ Folder Problem
I edited config.toml, wrote rules in AGENTS.md, and nothing stuck. Turns out the folder structure itself was the issue, not my settings.
Codex Moved Into Claude Code, and That Says Everything
OpenAI shipped Codex as a Claude Code plugin on the same day Anthropic announced Computer Use. I think it's the smartest concession of 2026.
2026년 Claude Code 의 승부처는 도구가 아니라 레이어입니다
Blog version of a 2026-03-29 LinkedIn note — same claims, cleaned structure for reading.
️ 2026년 1분기 AI 활용 4가지 방향성이 드러나기 시작했습니다
Blog version of a 2026-03-28 LinkedIn note — same claims, cleaned structure for reading.
OpenAI Sora의 실패가 증명한, 생성 AI 시장의 4가지 냉혹한 현실
Blog version of a 2026-03-25 LinkedIn note — same claims, cleaned structure for reading.
Create Three Spec Files Before Using Claude Code and Codex
I spent a year getting wildly inconsistent results from Claude Code and Codex. Three spec files, each with a distinct role, fixed it.
5 Settings That Separate the Top 0.01% Claude Code and Codex Users
Subscribing puts you in the top 0.3%. These five configurations — agents, teams, MCP, monitoring, automation — push you into the top 0.01%.
31 AI Coding Agent Terms You Should Know, Sorted Into Five Pillars
I classified every term I kept encountering while using Claude Code and Codex daily. Five groups emerged, and they map the entire system these tools run on.
Claude Code 29 Tools vs Codex 7 Tools: The Design Philosophies Are Polar Opposites
I dug into SDK type definitions and system prompts for both tools. The 29 vs 7 gap isn't about feature count. It's about two fundamentally different answers to the same question: how should an AI coding agent interact with your system?
AI 에이전트에게 작업을 시킨 다음 인간이 해야 할 일은 시각화입니다
Blog version of a 2026-03-12 LinkedIn note — same claims, cleaned structure for reading.
How Codex Solves the Compaction Problem Differently
I reverse-engineered how Codex handles context overflow compared to Claude Code. The answer involves AES encryption, session handover patterns, and KV cache tricks.
Claude Code Just Reset Everyone's Weekly Limits to Zero — Here's What Happened
A race condition between Auto Memory and context compaction in Claude Code v2.1.59–v2.1.61 broke prompt caching and corrupted sessions. Anthropic reset all weekly limits as compensation.
free-router: I Built a CLI That Finds Free AI APIs So You Can Vibe Code for $0
I couldn't sleep after a conversation about shipping more work publicly, so I built free-router at 3am. It pings free AI models in real-time and wires them into your coding tools with one keystroke.
4 Updates from Anthropic, OpenAI, and Google: The Hidden Pattern
Three companies updated their coding agents at the same time. The directions overlap. The real battleground isn't models; it's how fast they absorb developer workflows.
The Cache Design That Cuts Claude Code API Costs by 90%
My API costs jumped 10x when the cache broke in production. The same day, Anthropic engineers explained exactly why.
The Web's Top Customer Is Shifting from Humans to AI
From Cloudflare and Vercel's Markdown for Agents to Google's WebMCP, reading and writing are being standardized simultaneously, ushering in the Agent-Native Web era.
ChatGPT Pro for $20/Month? Only Koreans Get This Deal
Korea-exclusive KakaoTalk promotion offers ChatGPT Pro at 29,000 KRW instead of $220/month, plus the new Codex-5.3-Spark delivers 1,000 tokens per second.
Why OpenAI Hired the OpenClaw Creator - The AI-Native Messenger Era Begins
Peter Steinberger joining OpenAI isn't just a talent grab. It signals the dawn of AI-native messengers that could redefine how we communicate.
How OpenAI Built 1 Million Lines of Code Using Only Agents: 5 Harness Engineering Principles
OpenAI's Codex team built a 1M-line codebase using only AI agents. Here are the five harness engineering principles they discovered along the way.
Codex 에이전트에게 100만 줄을 맡긴 OpenAI, 사람이 한 건 딱 5가지였습니다
Blog version of a 2026-02-11 LinkedIn note — same claims, cleaned structure for reading.
The Token Divide: How AI Pricing Creates New Economic Inequality
Opus 4.6 Fast mode costs $150/output tokens. This isn't just pricing, it's the birth of a new economic divide where token access determines competitive advantage.
AI Adoption Now Divides Enterprise Value by 4x - The Data Is In
Meritech Capital's analysis of 100+ public software companies reveals a stark valuation gap between AI-executing and non-AI firms.
The AI Flywheel Paradox: OpenAI's Bet on More Compute Amid Overcapacity Fears
While the market warns of GPU overcapacity, OpenAI declares it needs even more compute. The real winner won't be whoever has the most power - it'll be whoever closes the gap between AI capability and actual user experience.
OpenAI & Google's 2026 Declaration: The AI Price War Has Begun, and Now Is the Best Time to Jump In
OpenAI and Google are racing to launch affordable AI plans while Chinese competitors shatter price floors. Here's why this moment is your best entry point.
The AI Wrapper Era Is Over. The Age of Claude Agent Wrappers Has Begun.
Anthropic's Tariq Shihipar breaks down what it actually takes to build production-grade agents - from Bash-first tooling to file-system-driven context engineering.
Claude Code Was for Developers - Cowork Is for Everyone
Anthropic launches Cowork, an autonomous agent that reads, edits, and creates files on your local machine. Vibe coding meets vibe working.
The AI War Was Won by Focus - What Anthropic's Opus 4.5 Proves About Strategy
Anthropic's Claude Opus 4.5 didn't just set new benchmarks. It proved that going all-in on text, code, and agents while competitors spread thin is the winning play.
ChatGPT Is Android, Claude Is iOS
Why $300B evaporated from SaaS stocks as ChatGPT and Claude race to become the AI app store - and what the 2008 mobile wars tell us about what comes next.
Claude in Excel Is a Declaration of War on AI+X Startups
Anthropic's Claude in Excel reveals the gap between AI-augmented and AI-native - and why most startups building 'AI + X' products won't survive 2026.
Manus Acquired by Meta for $300M Reveals Core Agent Development Principles with LangChain
Manus shared the hard-won lessons behind building production AI agents - from context rot to evaluation rethinking - in a joint presentation with LangChain.
Inside the $3.6B Secret Behind Manus: Why AI Agents Actually Fail
Meta acquired Manus for $3.6 billion. The secret wasn't a bigger model - it was context engineering. Here's what most AI agents get wrong.
What Meta's Manus Acquisition Tells Us - Why Startups Can No Longer Afford to Stay Local
Meta acquired Chinese AI startup Manus for billions. This deal reveals a new reality: going global isn't a growth option - it's a survival strategy for every startup in the AI era.
Dissecting Oh-My-OpenCode and the Future of Context Engineering
A deep dive into Oh-My-OpenCode's multi-agent orchestration architecture - how programmatic context isolation, parallel execution, and evidence-based research are redefining what AI coding agents can do.
7 Building Blocks of AI Agent Design, Learned from Opencode Docs
Opencode's open-source documentation doubles as an introductory guide to agent architecture. Here are the seven core concepts every developer should understand.
Hacking Day UI UX QA Flask Folo
Blog version of a 2026-02-04 LinkedIn note — same claims, cleaned structure for reading.
Claude Code AskUserQuestion
Blog version of a 2026-02-02 LinkedIn note — same claims, cleaned structure for reading.
Context7, 단순 MCP 연결 말고 스킬, 서브에이전트로 컨텍스트를 절약하세요
Blog version of a 2026-01-17 LinkedIn note — same claims, cleaned structure for reading.
MCP Tool Search Tool
Blog version of a 2026-01-15 LinkedIn note — same claims, cleaned structure for reading.
Cursor Codex Gemini Cline AI Plan Mode
Blog version of a 2026-01-13 LinkedIn note — same claims, cleaned structure for reading.
바이브 코딩 시대, 창업가의 역할이 '코더'에서 '편집장'으로 바뀌고 있습니다.
Blog version of a 2026-01-11 LinkedIn note — same claims, cleaned structure for reading.
AI 슬롭을 막는 컨텍스트 엔지니어링 관점에서의 클로드 코드 실전 가이드
Blog version of a 2026-01-08 LinkedIn note — same claims, cleaned structure for reading.