# What Is the Model Context Protocol (MCP)?

> Model Context Protocol (MCP) is an open standard introduced by Anthropic in late 2024 that lets AI assistants connect to external tools and data sources through a uniform interface. Instead of every model integrating every tool one by one, an MCP server exposes its capabilities and any MCP-aware client — Claude Desktop, Cursor, VS Code, custom agents — can use them.

*Source: https://www.whisper.security/glossary/mcp*
*Published: 2026-05-05*
*Last updated: 2026-05-05*

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## Why MCP Exists

Before MCP, integrating an LLM with an external API required either bespoke function-calling glue per model or a custom agent framework per tool. MCP standardizes the contract: tools expose a manifest, clients discover it, calls flow through a defined protocol. It is to AI tooling roughly what USB or LSP was to its respective domain — a shared interface that lets components mix freely.

## The Three Protocol Concepts

- **Tools** — functions the AI can invoke (run a query, read a file, send a message).
- **Resources** — data the AI can read (documents, database entries, configuration).
- **Prompts** — pre-defined templates the AI can use as starting points for a task.

## Transports

- **stdio** — local subprocess, good for local tools.
- SSE (Server-Sent Events) — the older HTTP transport, now deprecated in favour of Streamable HTTP, which mcp.whisper.security uses.
- **HTTP / streamable HTTP** — request-response and streaming variants.

## Why MCP Matters for Security Tools

Security analysts increasingly drive investigations through AI assistants. An MCP server is the piece that lets the assistant *call* security tools mid-conversation: querying threat-intel data, resolving a domain, looking up an ASN, pivoting through historical infrastructure. A security tool without an MCP interface is one the AI agent cannot reach.

## MCP and Whisper

[Whisper](https://www.whisper.security) ships an MCP server at **mcp.whisper.security**. AI agents — Claude Desktop, Cursor, Continue, Windsurf, custom MCP clients — query the [knowledge graph](/glossary/knowledge-graph) directly. Read more on the [AI Context page](/products/integrations#mcp) or in the [MCP setup docs](/docs/ai/mcp/setup).

## See it in practice

Run it live in these use cases: [Ground your agent in live infra](/products/intelligence/use-cases/threat-investigation/indicator).

## Where this shows up

See it in a live investigation: [Ground your AI agent before it acts](/products/intelligence/use-cases/threat-investigation/indicator).

Go hands-on with [the MCP setup guide](/docs/ai/mcp/setup).

## Related Terms

- [Knowledge Graph](https://www.whisper.security/glossary/knowledge-graph.md)
- [Cypher](https://www.whisper.security/glossary/cypher.md)
- [Infrastructure Intelligence](https://www.whisper.security/glossary/infrastructure-intelligence.md)