Field notes

Applied AI, in the open

Deep-dives on Claude Skills, agent workflows, and the automation engineering behind the techsy.io library.

Claude Code subagents process diagram: one main session fanning out to worker agents that write research.md, brief.md, en.md and meta.json

AI AgentsJul 21, 2026· 14 min read

Claude Code Subagents: What We Learned Running 18 of Them in Production

Every subagent guide demonstrates with the same code-reviewer toy example. We run 18 subagents in production: the real directory listing, the 6/11/1 model split, how they hand off work through files, and the failure modes we hit.

Mert Batur · Author

Running multiple Claude Code sessions in parallel — session status board

AI AgentsJul 18, 2026· 7 min read

How to Run Multiple Claude Code Sessions at Once (Without Losing Track)

A practical workflow for running 3+ Claude Code and Codex sessions in parallel without losing track of which one needs you — from a team that does it on client work every day.

Mert Batur · Author

How to write a Claude skill — annotated SKILL.md file structure

Claude SkillsJul 18, 2026· 11 min read

How to Write a Claude Skill (SKILL.md Structure + Real Examples)

A practical guide to writing a Claude skill: the SKILL.md structure, the frontmatter rules, and the description mistakes that stop skills from triggering — from a team running 25 of them in production.

Mert Batur · Author