Understanding "Skills" in LangChain: Loading Expertise On-Demand

Short summary

The article introduces the 'skills' pattern in LangChain, which solves prompt bloat in multi-domain AI agents by using progressive disclosure. Instead of cramming all domain instructions into one system prompt, each domain's rules live as separate skills loaded on-demand via a load_skill tool. The agent starts with a lightweight base prompt and fetches relevant instructions only when needed, reducing token costs and preventing instruction bleed.

• •Skills pattern separates domain instructions into individually loaded modules
• •Progressive disclosure avoids prompt bloat, token waste, and instruction bleed
• •Includes working code example with skill dictionaries and agent state management

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