OpenAI’s Codex context reduction for GPT 5.6 sparks dissatisfaction among developers

OpenAI’s recent update to its Codex coding agent has developers worrying over the impact of the change on large code repositories and long-running AI-assisted sessions. The update to the Codex CLI reduces the default configured input context window for GPT-5.6 to 272,000 tokens from 372,000 tokens. In practice, the update means the coding agent will retain a smaller amount of code, conversation history, and other session information before compacting older context to make room for new informatio