Design Skills That Compose Without Colliding
Once you have several skills, the failure mode changes: the wrong one fires. How to draw boundaries and chain skills deliberately.
The problem changes at three skills
One skill either fires or it does not, and both outcomes are easy to diagnose. Several skills introduce a new failure: the wrong one fires, does something plausible, and nobody notices that the better-suited skill was never considered.
The cause is nearly always overlapping descriptions. Two skills that both mention reviewing prompts will compete, and which one wins depends on wording you did not intend to be decisive.
Treat your descriptions as a single system rather than as independent files. When you add a skill, read it against the others and ask what would distinguish them from the outside, in the words someone would actually use.
Draw boundaries on the situation
Boundaries drawn on subject matter collide, because real work spans subjects. Boundaries drawn on the situation hold: not "pricing" and "proposals" but "a pricing page is not converting" and "a deal is agreed and nothing is written down".
Where two skills genuinely share a subject, state the exclusion explicitly in both descriptions. A sentence saying which neighbouring case belongs elsewhere is cheap and does more for reliability than any amount of instruction tuning.
If you cannot describe the boundary in a sentence, there probably is not one, and you have two versions of the same skill. Merging them is better than maintaining an ambiguity you will keep rediscovering.
4 more sections in this article
- Chaining deliberately
- Granularity
- Shared conventions
- Reviewing the set
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Published 14 August 2026. Last reviewed 17 August 2026. We re-read this library on a schedule and date every article, so you can see for yourself how current it is.