# jxnl.co

Jason Liu's blog at jxnl.co. Jason is the author of [Instructor](https://github.com/jxnl/instructor) — the Python library that pioneered Pydantic-based structured-output prompting before frontier providers added their own — and writes about AI agent workflows, structured output engineering, RAG productization, and (recently) using Codex and Claude Code for knowledge work, not just code.

The tone is operator-flavored: long pieces that describe how he actually uses tools day-to-day rather than benchmark posts or speculation. Pieces tend to coin reusable names for patterns — "compaction" for thread compression, "heartbeats" for self-scheduled checks, "steering" for mid-task message injection.

## Ingested articles

- [[jxnl-codex-maxxing]] (2026-05-10) — Codex-maxxing: the operating loop with durable threads, voice, steering, memory-as-files, Heartbeats, Goals, and the side panel