LLM - Personalization - Custom instructions

Codex - ChatGPT - Personalization - Custom instructions

Codex Rules: Global Instructions, AGENTS.md, and Mac App

https://kirill-markin.com/articles/codex-rules-for-ai/

My “prove it first” Custom Instructions for coding

Prompting

prompt

vittoroliveira

Jan 14 2026

https://community.openai.com/t/my-prove-it-first-custom-instructions-for-coding/1371664

AI agents running research on single-GPU nanochat training automatically

Andrej Karpathy - autoresearch

https://github.com/karpathy/autoresearch

Personal Prompt Engineer

By Bill Davis 

https://chatgpt.com/g/g-CXVOUN52j-personal-prompt-engineer

PromptLab is a free, lightweight open-source tool to maintain all stages of prompt lifecycle- development, evaluation and deployment. It simplifies LLMOps, enabling workflows that range from simple prompt evaluation to complex agent evaluation.

https://github.com/cognix-labs/promptlab    

Codex Prompting Guide

https://developers.openai.com/cookbook/examples/gpt-5/codex_prompting_guide

Best practices

Getting started with Codex and proven practices for better results

https://developers.openai.com/codex/learn/best-practices

Customization

How to customize Codex with project guidance, skills, MCP, and subagents

https://developers.openai.com/codex/concepts/customization

ChatGPT custom instructions

https://help.openai.com/en/articles/8096356-chatgpt-custom-instructions

Codex - Advanced configurations - Winsock’s personal library

Codex

custom-instructions

codex-app

output-markdown 

https://community.openai.com/t/codex-advanced-configurations-winsocks-personal-library/1376527