Agentic AI Infrastructure
MCP · A2A · NLWeb
The Three Agentic Protocols
A visual guide to the foundational protocols enabling AI agents to use tools, collaborate with each other, and interact with the web.
Protocol Overview
What Each Protocol Does
MCP
Model Context Protocol · by Anthropic (2024)
Standardizes how LLMs connect to external tools, APIs, databases and resources. Like a USB-C port — one universal interface for any tool or data source.
A2A
Agent-to-Agent Protocol · by Google (2025)
Enables autonomous AI agents to discover, communicate and delegate tasks to one another across different frameworks and vendors. Agents as a network.
NLWeb
Natural Language Web · by Microsoft (2025)
Adds a conversational interface layer to any website. Sites expose structured data via schema.org so AI agents can query and navigate them in natural language.
Architecture
How Each Protocol Flows
🔌 MCP — Model Context Protocol Flow
🤝 A2A — Agent-to-Agent Protocol Flow
🌐 NLWeb — Natural Language Web Flow
Real-World Scenarios
Protocol Examples
User asks Claude to “Fix the failing tests in my repo and push a commit”
filesystem/read tool → reads test filesshell/run → runs pytest, gets errorsfilesystem/write → applies fixesgit/commit_push → done ✓User: “What’s the status of my order #8821?”
get_order(id: "8821")User: “Write me a market analysis report on EVs”
agent.json cardUser: “Plan and book a 5-day Tokyo trip for 2”
Agent: “Find a waterproof hiking boot under $150 size 11”
boots.com/nlwebProduct typeAgent: “Summarize today’s AI news from major tech blogs”
Article objectsSide-by-Side
Protocol Comparison
| Attribute | MCP | A2A | NLWeb |
|---|---|---|---|
| Created by | Anthropic (2024) | Google (2025) | Microsoft (2025) |
| Primary purpose | LLM ↔ Tools/Data | Agent ↔ Agent | Agent ↔ Web |
| Transport | stdio, HTTP SSE | HTTP/REST, SSE | HTTP POST/GET |
| Data format | JSON-RPC 2.0 | JSON (Task objects) | JSON-LD, schema.org |
| Discovery | Pre-configured servers | Agent Cards (.well-known) | Site’s /nlweb endpoint |
| Best for | Tool integration, DB access, file ops | Complex multi-agent workflows | Web browsing agents, e-commerce |
| Auth | OAuth 2.0, API Keys | OAuth 2.0, JWT | Standard HTTP auth |
| Analogy | USB-C for AI tools | HTTP for agents | RSS/APIs for natural language |
Together
All Three Working Together
Combined Agentic Stack — “Plan my weekend trip and blog about it”