> ## Documentation Index
> Fetch the complete documentation index at: https://docs.llmeasy.ru/llms.txt
> Use this file to discover all available pages before exploring further.

# MCP vs API Key and Base URL

> Understand the difference between MCP, API Key, Base URL, model protocols, and tool protocols.

## Short answer

MCP is a protocol for connecting AI tools to external tools, data sources, and context. API Key and Base URL are model request authentication and routing settings.

MCP answers: what tools and data can the agent use? API Key / Base URL answers: where do model requests go and how are they authenticated?

Configuring MCP does not configure the model API. Configuring a model API does not automatically give the tool external system access.

## Comparison

| Item             | MCP                                                          | API Key / Base URL                                  |
| ---------------- | ------------------------------------------------------------ | --------------------------------------------------- |
| Main job         | Tool, data source, and context integration                   | Model requests, authentication, routing             |
| Common targets   | Local services, databases, files, browsers, business systems | OpenAI-compatible or Anthropic-compatible endpoints |
| Main risk        | Tool permissions, data access, side effects                  | Secret leakage, protocol mismatch, model cost       |
| Determines model | No                                                           | Usually yes                                         |

## When people mix them up

* They think MCP changes the model.
* They think changing Base URL connects local tools.
* They treat an MCP server as a model provider.
* They put a model API Key into MCP configuration.
* They do not know whether a tool expects OpenAI-compatible or Anthropic-compatible API.

## How to decide

If you want an agent to access a database, browser, filesystem, internal system, or extra tool, look at MCP.

If you want to switch model, gateway, billing account, or provider, look at API Key, Base URL, and protocol.

If a workflow needs both a model switch and external tools, configure both layers and review permissions separately.

## About LLMEasy

LLMEasy is the model API layer, not an MCP server. It handles API Key, Base URL, model routing, and usage records.

You can use LLMEasy and MCP together: LLMEasy handles model requests, while MCP handles tool and context extension.

## Related docs

* [OpenAI-compatible API vs Anthropic-compatible API](/en/faq/concepts/openai-compatible-vs-anthropic-compatible)
* [How to configure MCP in Claude Desktop](/en/faq/claude-desktop/mcp)
* [How to configure MCP in Cursor](/en/faq/cursor/mcp)
* [Claude Code permissions and hooks](/en/faq/claude-code/permissions-and-hooks)

## References

* [Claude Code MCP documentation](https://docs.anthropic.com/en/docs/claude-code/mcp)
* [Model Context Protocol introduction](https://modelcontextprotocol.io/docs/getting-started/intro)
* [Anthropic MCP overview](https://docs.anthropic.com/en/docs/agents-and-tools/mcp)