ACAgentic Craft

Intermediate~55 minHazelJS

Tools, Skills, and MCP

Design tool contracts and choose direct @Tool, Skillgate, or MCP under Agent OS governance.

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Deepen ToolRegistry design: schemas, side-effect classes, Skillgate curation, MCP export/import—without inventing allow-list APIs.

Learning outcomes

  • Specify @Tool contracts with side-effect and approval metadata
  • Choose Skillgate vs MCP vs direct tools with governance in mind

Lessons

  1. 01Tool Contracts and Side Effects
    Design @Tool schemas with side-effect class, timeouts, approval, and idempotency as first-class contract fields.
  2. 02Skillgate and MCP Integration Styles
    Compare direct @Tool, Skillgate.fromOpenApi, and MCP export/import under one ToolRegistry policy plane—with code.

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