codex-prompt-engineering
Codex Prompt Engineering
Knowledge snapshot: 2026-02-20
Purpose
Use this skill to design or review prompts for Codex/GPT coding agents with focus on:
- quality and reliability
- token efficiency
- correct tool usage
- safe autonomy
Use When
- Writing or revising system prompts for coding agents
- Debugging weak agent behavior (stalling, verbosity, bad tool calls)
- Calibrating
reasoning_effort(none|low|medium|high|xhigh) - Defining tool orchestration and planning behaviors
- Building evaluation loops for prompt iteration
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