@RealCodedAlpha: After seeing this suspected Anthropic internally optimized Fable 5 Prompt structure, I realized: most people are writing Prompts wrong from the start! Many think a good Prompt = longer, more complex, more techniques, more role settings. But the structure given by this image is very…

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Summary

This tweet introduces a Fable 5 Prompt structure that is suspected to be internally optimized by Anthropic, emphasizing that writing prompts should focus on goals, boundaries, and acceptance criteria rather than lengthy instructions. Especially for stronger models like Claude and Codex, avoid teaching the model how to think.

After seeing this suspected Anthropic internally optimized Fable 5 Prompt structure, I realized: most people are writing Prompts wrong from the start! Many think a good Prompt = longer, more complex, more techniques, more role settings. But the structure given by this image is very simple: Context: What's the background Request: What exactly do you want the model to do Output Format: How should the result be delivered Constraints: What cannot be assumed or overstepped Checkpoint: When to stop and ask you But for stronger models like Fable 5, Claude, Codex, the real key is not to "teach the model how to think," but to clearly define the task boundaries! Especially the last one, Checkpoint, is important: Only pause in three situations: 1. Involves irreversible operations 2. Task scope changes 3. Requires user input Otherwise, the model should continue completing the task and report at the end. This is how Prompts should be written in the Agent era. The stronger the model, the less nonsense it needs. It needs goals, boundaries, and acceptance criteria. From now on, before writing a complex task, check these 5 parts: Context 、Request、Output Format 、Constraints 、Checkpoint
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Cached at: 07/03/26, 04:40 PM

After seeing this suspected internal Anthropic optimized Fable 5 Prompt structure, I realized: most people are writing prompts in the wrong direction from the start!

Many think a good prompt = longer, more complex, more tricks, more role-playing.

But the structure shown in this image is very simple:

Context: What is the background
Request: What exactly you want the model to do
Output Format: How the result should be delivered
Constraints: What can’t be assumed or overstepped
Checkpoint: When to stop and ask you

For stronger models like Fable 5, Claude, Codex, the real key is not “teaching the model how to think”, but clearly outlining the task boundaries!

Especially the last point — Checkpoint — is important:

Only pause in three cases:

  1. Involves irreversible operations
  2. Task scope changes
  3. Needs user input

Otherwise, the model should continue the task and report only at the end.

This is how prompts should be written in the Agent era.

The stronger the model, the less you need to write a bunch of fluff.

What it needs is the goal, boundaries, and acceptance criteria.

Before writing a complex task, first check these 5 parts: Context, Request, Output Format, Constraints, Checkpoint.

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