Action guide
How MCP works
How host, client, and server really connect in MCP. Integrate and debug like you own the wire, not like a tourist squinting at JSON.
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Why subscribe
MCP shows up as neat JSON in posts. You need a runtime map. Who caches what. Who calls whom. Where your server actually runs. Wire that picture before you bolt this onto prod traffic.
For: Engineers wiring LLM apps to tools and resources. People who think in protocols and timeouts. Not slogans.
- A crisp model of host, client, and server responsibilities
- Clarity on primitives and lifecycle flow before you debug weird timeouts
- A foundation for integrations you can reason about in code review
- Full protocol walkthrough in plain language
- Concrete flows from discovery to execution
- Quick-reference framing you paste next to your IDE
- Separates concerns the way a real system boundary should
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What you’ll learn
How Model Context Protocol fits together at runtime: discovery (host connects, server advertises tools/resources/prompts), what the LLM sees before it answers, how a structured tool call is emitted and forwarded by the MCP client, and what happens when the server runs the real action and returns a result-illustrated with a concrete request/response flow in the full guide.
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