Agent Skills: optimize-gpt-5-6-prompts

Review, simplify, migrate, and create prompts, tool descriptions, agent instructions, or prompt stacks for GPT-5.6 and the GPT-5.6 family. Use when a user provides a prompt and asks to optimize, critique, streamline, rewrite, upgrade, or adapt it for GPT-5.6, or explicitly invokes this skill to improve an existing prompt or draft one from scratch. Do not trigger merely because prompt text appears in unrelated code or documentation without an intent to create, evaluate, or change prompting behavior.