TL;DR of my new article: Fable 5 and GPT-5.6 have finally been live at the same time for 7 days. I ran
@slashlast30days on both 20+ times and collated what actually stuck. Both labs shipped a prompting guide the same week, and they agree: you're over-prompting.
๐ฏ Goal, not steps. "Fable 5 degrades when you over-instruct it." Outcome, context, bounds, what done looks like. Then get out of the way
โ๏ธ Say everything exactly once. OpenAI's own evals: deleting redundant instructions = 10-15% better scores, 41-66% fewer tokens, 33-67% cheaper
๐ช "Fable 5 orchestrates, cheap models execute" - 96% of the performance at 46% of the cost. 1,246 upvotes, loudest signal of the window
๐ฅ Run them as rivals: both get the same goal at xhigh, the winner's design ships, the loser tears it apart at checkpoints (302 upvotes)
๐ธ Route by dollars-per-task. "Terra tying with fable at 1/4 the cost ๐" (183 upvotes). Altman: 5.6 is 54% more token efficient
๐๏ธ The effort dial is a trap. High is the default for a reason. xhigh mostly buys you a bigger bill
๐๏ธ Give it a notes file. One markdown file of lessons turns a goldfish into a colleague
๐งพ Make it audit every claim against a tool result. Anthropic says this nearly eliminated fabricated status reports
๐ค Never ask Fable 5 to show its reasoning. It can trigger a refusal that silently falls you back to Opus 4.8
๐๏ธ Set text.verbosity once instead of typing "be concise" forever
The pattern: your leverage moved out of the prompt and into the process. Routing, orchestration, verification. The model stopped being the bottleneck. You are the variable now.