Double-Check System Prompts in Custom Harnesses

pvncher · x · 2026-07-12

A reminder: if you are using a model inside a custom harness, check whether your system prompt matches the default Codex configuration. The context also mentions that this might explain the high costs of certain "code-fixing" loops, and whether guidance can be placed into skill or subagent configurations to force lower reasoning.

Related event: Codex Sub-Agent Differences Traced to Training and System Prompts(3 posts)→

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