Skills vs Tools vs Rules vs MCP Tools: Hands-On with Langchain, AWS Bedrock Nova

Skills are reusable abilities an AI agent uses to get things done, like writing, reasoning, or coding tasks . The concept was introduced by Anthropic and is widely used in modern coding agents (AWS Kiro, OpenCode, ClaudeCode, etc.). In this post, I want to show how to implement basic skills using Langchain and AWS Bedrock Nova. What are Agent Skills? Agent skills are what an AI can do, thinking through problems , making plans, using tools, remembering things, and talking clearly. They matter bec