Claude Skills
Anthropic's implementation of the Agent Skills pattern: a directory-based system where each skill is a folder containing a SKILL.md instruction file, optional scripts, and reference documents. The model loads a short index of available skills into its context, then loads a specific skill's full contents only when triggered. Skills work across Claude apps (Claude Code, Claude Agent SDK, Claude.ai) and are portable between projects.
Written by Max Zeshut
Founder at Agentmelt · Last updated Sep 9, 2026
Frequently asked questions
- How do Claude Skills differ from custom system prompts?
- A custom system prompt is one fixed block of instructions loaded on every call—great when behavior is the same across all tasks. Skills are conditional: dozens of focused instruction sets, only loaded when the model decides one applies. For an agent that handles 10 distinct task types, a skill per type is dramatically cheaper and more reliable than a 10× longer system prompt that covers them all up front.