
GPT-5.6 Luna: the model that became my default in Codex
After nearly 10 billion tokens in Codex, why GPT-5.6 Luna became my default model: cost, performance, context, and limits.
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After nearly 10 billion tokens in Codex, why GPT-5.6 Luna became my default model: cost, performance, context, and limits.

LLMs can converse, but they do not share a stable domain model. Ontologies, knowledge graphs, and semantic validation can give agents a common vocabulary, safer actions, and verifiable memory.

The agent is no longer the whole product. The next jump is the layer above it: memory across sessions, coordination across agents, context across repos, and automatic optimization of the harness itself.

The generic agent looks simple until it becomes a giant context window with too many tools, too many permissions, and too much cost. Domain-specific agents trade that accumulation for composition, clear boundaries, and cheaper execution.

Your agent nailed the demo and everyone loved it. But how do you know it actually works? If the answer is 'we tested it and it seemed fine', you are operating in vibes mode. And vibes don't scale.

Autonomous agents can turn a trivial task into a financial black hole because token consumption is massive, stochastic, and difficult to predict.

You have probably experienced this: one moment, GPT or Claude solves a complex coding problem in seconds; the next, the same AI forgets basic context or invents nonexistent information.

There is an efficiency gulf between biological architecture and silicon. While a 12-year-old child already masters human language, models like GPT-3 require far more data.

If you are starting to venture into AI Engineering and want to go beyond the basics, you need to deeply understand what **Retrieval-Augmented Generation (RAG)** is.

You know when you are trying to solve a complex problem with AI and it feels like a single model cannot handle the job? Multi-agent systems help, but only in the right cases.