MCP standardizes agent-tool connections, but its method of advertising all tools at startup can consume enormous token counts (e.g., 50,000 tokens for "Hello"). This creates a significant, often overlooked, context bloat issue that requires mitigation via patterns like loading agent skills on demand.
MCP is not a universal solution. For single-purpose agents with a fixed, small toolset, the protocol's overhead adds unnecessary complexity. Direct, handcrafted integrations are more efficient for such focused projects, reserving MCP for multi-agent ecosystems or reusable tooling platforms where its value is maximized.
MCP doesn't replace core agent patterns like RAG or the "LLM + tools" loop. Instead, it serves a specific function: standardizing the "tools" component. This makes tools composable and reusable across agents, acting as the interoperability layer that allows complex, multi-agent systems to share capabilities efficiently.