A Dev.to article describes a problem with integrating Model Context Protocol (MCP) tools into AI agents: when an agent connects multiple MCP servers, the system can load large numbers of tool definitions into the model’s context window before the agent answers any user request. The author estimates that 50 MCP servers, each defining 10–20 tools, can produce roughly 500–1,000 tool schemas and tens of thousands of tokens of tool metadata. The article argues this “tool overload” reduces the context available for the actual task, which can lead to lower response quality and agent confusion.

To address this, the article proposes “progressive tool routing,” a method that injects only a small set of relevant tool schemas into the LLM context for each request. It describes a multi-layer approach: semantic search against a directory of MCP tools to find matches for the current prompt; a router that selects only the most relevant tool schemas to inject; and “universal parity,” where tool signatures are kept consistent across multiple client environments.

The author reports reductions in tool-related context usage (about 95%) and improved tool selection accuracy after applying this approach.