"I Wired DeepSeek V4 Into Claude Code and Codex CLI Without Touching the Tools"

DeepSeek V4 dropped, the benchmarks looked aggressive, and the price-per-million-tokens looked even more aggressive. The first thing I wanted to know wasn't "is it as good as Claude Opus 4.6 or GPT-5.4?" — it was "can my actual coding agents use it without me rewriting half my workflow?" Because that's the part nobody benchmarks. A model can be the cheapest reasoner on the leaderboard and still be useless to me if Claude Code, Codex CLI, and Gemini CLI can't talk to it the way they expect to. He