Agent Layer

Tools, Protocols & Interoperability

Explain how agents discover capabilities, call systems and communicate across boundaries.

Why This Matters

Tool calling without contracts is an integration accident. Protocols define capability discovery, authorization, and what happens when two agents meet across an org boundary.

Architecture Position

Tools and protocols connect the Agent Layer to enterprise APIs and to other agents. Security and identity wrap every hop. See it on the architecture map.

Start Here

Core Concepts

Tool Calling

  • Function calling
  • Tool schemas
  • Structured arguments
  • Tool errors

Capability Systems

  • Capability discovery
  • Tool registries
  • Capability contracts

MCP

  • MCP fundamentals
  • MCP architecture
  • Clients
  • Servers
  • Authorization
  • Security

Agent Communication

  • Agent-to-agent communication
  • A2A
  • Handoffs
  • Delegation

Enterprise Protocols

  • OpenAPI
  • AsyncAPI
  • CloudEvents
  • Webhooks
  • JSON Schema

Advanced Coordination

  • Outcome coordination
  • Protocol contracts
  • Cross-domain orchestration

Advanced

Advanced material

Deeper guides for this domain are on the way.

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Architecture Patterns

Applied patterns for this domain live in the pattern library.

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Case Studies

Enterprise walkthroughs that apply this topic in a full system.

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Related Topics

Roadmaps

This topic appears in the Enterprise AI Architect path.

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Learn this as part of the Agent Systems Architecture course.

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