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The Difference Between A Chain Of Skills And One Overloaded Skill

By Nigel Guy · 3 min read

A skill that started doing one thing well tends to grow. Someone notices it could also handle a related case, and then another, and each addition feels small at the time. What you end up with, a year in, is a single file that branches heavily depending on what you feed it, with a guardrails section longer than the mechanism it's guarding, and nobody quite sure which parts apply to which situation. The fix isn't a longer, better-organised document. It's usually several smaller skills with a clear handoff between them.

The mechanism

Signs a skill has become overloaded rather than just long:

• It branches heavily by scenario, with large sections that only apply to some inputs and get skipped entirely for others.
• Its guardrails section has grown to cover cases the original mechanism was never designed around, patched on as afterthoughts.
• You find yourself explaining out loud which part actually applies this time, because the document alone doesn't make it obvious.

If that's what you're looking at, splitting into a chain:

1. Find the natural handoff points — the places where the output of one part of the current skill is already, in effect, the clean input to the next part. These are usually easier to spot than expected, because the overloaded skill's own internal structure has already drawn the lines; you're just formalising them.
2. Give each resulting skill its own single trigger. If you can't state in one sentence when this piece runs, on its own, it hasn't actually been separated yet — it's just been copied into a second file.
3. Give each its own guardrails section, scoped to what it actually does. A narrower skill should have a narrower, more specific guardrails section than the overloaded original had for that same case.
4. Make the format of the handoff between them explicit — what exactly passes from one skill to the next, and in what shape. This is the part most likely to be skipped, and it's the part that determines whether the chain actually works end to end or just looks tidier on disk.
5. Test each link on its own before testing the whole chain. A chain that fails is much easier to debug when you already know each individual link passed its own test in isolation.

What to skip

Skip splitting a skill that's merely long but genuinely doing one thing — length by itself isn't the signal; branching complexity by scenario is. Plenty of skills are long because the single procedure they follow has many steps, and that's not the problem this fix addresses. And skip chaining skills purely for tidiness if nobody but you will ever read or maintain them — the overhead of more files is a real cost, and it should be paying for actual clarity, not just aesthetic preference.

Guardrails

• A chain adds a coordination cost the single overloaded skill didn't have — someone has to keep the whole sequence working, not just each piece. Don't split without accounting for who maintains the chain as a whole, not just its parts.
• The handoff format between links is the most common place a chain quietly breaks; if you only test each link in isolation and never the full sequence, you haven't actually verified the chain works.
• This is a judgement call about complexity, not a fixed threshold — some overloaded-looking skills are still better left as one document, particularly if the branches share most of their logic and would mostly duplicate each other once split.

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