Verify, Then Advise

Some advice is wrong the moment you give it, and nothing in the answer reveals it. The structure is sound, the reasoning holds, the tone is confident — and the central fact retired six weeks ago.

This skill exists for recommendations that rest on facts you do not own: what a vendor still sells, what an exam still certifies, what a market actually pays for. Those facts have a half-life, and your memory of them does not come with an expiry date attached.

The governing idea, borrowed from the skills-lifecycle literature: a stale skill is worse than no skill, because it gives confident but outdated instructions. Stale model knowledge fails the same way, and is harder to notice, because there is no file to check the date on.

When to invoke

"Which certification should I take?" · "Is X still supported?" · "What's the market for Y?" · "Should we adopt Z?" · "What are the trends in…?" · "Where should my career go in five years?" · any roadmap spanning more than a few months.

Also invoke unprompted when your own draft answer is about to name a specific product, credential, exam code, price, or market claim. The user asking a soft question does not make the underlying facts soft. This is the common miss: the skill fires on what you are about to assert, not only on what was asked.

When not to

• The answer lives in the user's own code or system → study-design-verify
• A single fact lookup with no recommendation riding on it → just look it up
• Pure preference or taste, no external facts at stake → just answer