When to reach for it
- Recurring complex solution paths need to be optimised.
- The agent must continuously adapt in a dynamic environment.
Skill Build.
Turn winning trajectories into named, reusable procedures.
The agent distils successful action sequences into reusable, named skills — often executable code — and stores them in a growing skill library it retrieves and composes on future tasks, instead of re-planning from scratch. This is procedural memory.
In practiceAn automation agent derives a reusable 'export-to-CSV' skill from three successful runs of that task, then calls it directly on subsequent similar requests without re-planning from scratch.
When it backfires
- Tasks are strictly one-off.
- The environment requires static, highly predictable behaviour.
The tradeoff
Continuous performance improvement is gained against the risk of over-fitting or catastrophic forgetting of older skills.
What it actually does.
A learned skill is saved once and reused later.
Two ways this pattern will hurt you.
Skills overfit to a single trajectory
A skill is extracted from one successful run. It encodes accidental details — exact phrasing, ordering, tool choice — and breaks on the next variant.
Fix · Require N successful runs of similar shape before promoting a candidate to a skill. Generalise parameters by diffing the runs.
A flawed skill silently poisons every task that reuses it
Once promoted, a skill is called without re-checking. A subtle bug — or a tool surface that later changed under it — now corrupts every downstream task that retrieves it.
Fix · Attach a regression test to each skill; re-validate on promotion and whenever a referenced tool surface changes, and retire skills that fail rather than calling them blindly.
Where Skill Build is native.
Microsoft Agent Frameworkemerging supportAdaptable
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