Too Many MCP Tools: I Gave My Agent 61 and It Got Dumber

说明与用途

过多的 MCP 工具会降低代理的工具选择准确性。通过将活跃工具限制在 10‑15 个、使用子代理和将相关工具包装成意图驱动的工具，可以恢复准确性并减少上下文开销。

问题

An AI agent with too many Multi‑Channel Platform (MCP) tools mis‑selects the correct tool, leading to repeated wrong calls, context pollution, and reduced task accuracy.

结果

Limiting active tools to 10‑15 per agent and structuring them by domain or intent restored first‑call accuracy to ~90% and eliminated context pollution caused by repeated wrong tool calls.

工作流

• Identify and log all connected MCP tools.
• Delete unused servers and tools.
• Allowlist only essential tools per server.
• Create sub‑agents for distinct domains (code, docs, comms).
• Wrap multiple related tools into a single intent‑based tool.
• Monitor first‑call‑correct rate and tool usage logs.
• Iterate to keep tool count within 10‑15 per agent.
• Use dynamic tool loading if supported to reduce prompt tax.
• Adjust tool descriptions to match prompt vocabulary.
• Re‑evaluate accuracy after changes.

证据

First‑call‑correct rate went from ~92% at 12 tools to ~61% at 61 tools on the same task set.

来源

The fix is a tool budget: 10‑15 tools per agent, scoped sub‑agents, and wrappers that collapse a whole server into 2‑3 verbs.

来源