The Cloud Codex — field notes on building with AI agents
$ cat ./codex/README.md
Field notes on building with AI agents.
The economics and architecture of production AI — the harness around the model, what the tokens actually cost, and the platform engineering that keeps it production-grade.
by michael tuszynski — principal architect · ex-AWS · 25 years shipping production systems
115 essays est. 2023
// featured
ai-engineeringllm-infrastructurecost-optimization
Your Local LLM Bill Is Per Token. Your Real Cost Is Per Accepted Answer.
Per-token pricing hides the real cost of local LLMs: retries, escalations, and the human review minutes that dwarf the token bill.
// series
$ ls ./series --all →7-part series
Building an AI Assessment System
A field build of AI-graded assessment — grading written answers, testing the judge, red-teaming it, and measuring what actually moved the needle for students. Read in order.
// start here
$ grep -l signal ./essays
- An Engineer Costs $250K. Their Tokens Cost $20K. That Math Is a Trap.7 min read
- The Coding Agent Stack Has Two Layers6 min read
- Your Claude Plugin Marketplace Needs More Than a Git Repo5 min read
- What Local LLMs Actually Cost vs the API6 min read
- AI Agents Are Killing Seat-Based SaaS Pricing. Here's What's Replacing It.5 min read
- Build AI Systems That Survive the Platform Wars8 min read
// most recent
$ ls -t ./essays
[ 01 ]
The 26% Who Never Rolled Back an Agent Aren't Winning
[ 02 ]
AI Use Is a 50/50 Coin Flip. Coding Already Tipped 61% Autonomous.
[ 03 ]
The Meter Is Always Running
[ 04 ]
Your AI Coding Pilot Cost $80K and Shipped 9% Faster. Here's the Line Item Finance Missed.
[ 05 ]
The Bubble Popper and the Payoff Are the Same Thing
[ 06 ]
Torvalds' Best Review Trick Just Stopped Working
[ 07 ]
Attention Is the New Bottleneck. Engineer It Like One.
[ 08 ]
Where Your $20K in Tokens Actually Goes
[ 09 ]
Try It: A Working Assessment-First Course
[ 10 ] series·7/7
Instrument Like a Learning Scientist
[ 11 ] series·6/7
The Biggest Effect Size Was the Boring Feature
[ 12 ] series·5/7