A thread you can test
Prompt Harness
4 notes move from the word to a real choice at work — understand it first, then decide whether to use it.
Each note stands alone, or becomes the next step in this thread.
THE QUESTION THIS PAGE ANSWERS
ANSWER FIRSTWhat is Prompt Harness, and which AI decisions does it change?
Why layered management is necessary: identity, environment, and tool instructions — each independent, non-interfering This page keeps the related concepts, common mistakes, and practical notes in one reading thread.
First decide whether you are blocked by a definition, a choice, or verification; then choose the closest of the 4 notes below.
Start with “System Prompt Isn't a Blob of Text,” then restate the conclusion using your own task.
Do not treat every method in a topic as interchangeable. The answer changes with the input, risk, and acceptance bar.
THIS QUESTION THREAD
Put the word back inside the choice it changes.
System Prompt Isn't a Blob of Text
Why layered management is necessary: identity, environment, and tool instructions — each independent, non-interfering
Don't Show AI What It Doesn't Need
100 tools all in system? Token explosion. This calls for on-demand loading design
Skill: Operationalizable Prompt Modules
Files as config, version-trackable — managing Prompts like code
The Subtle Relationship Between Prompts and Caching
Change one character in System Prompt and the entire KV Cache is invalidated. Minimizing accidental cost