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
- How to configure MCP in Claude Desktop
- How to configure MCP in Cursor
- Claude Code permissions and hooks