Nous Research adds Tool Search to Hermes Agent to fix MCP tool context overload

Marktechpost reports that Nous Research has added Tool Search to its open-source Hermes Agent. The feature aims to reduce the context load caused by MCP tools. According to Anthropic, in a deployment with 5 MCP servers and 34 tools, each turn uses about 45,000 tokens, with 50% being tool schema overhead. This "MCP tax" raises costs (0.07-0.10 USD per cache miss) and lowers accuracy (models struggle with too many irrelevant tools). Tool Search loads tools on demand. The model searches, describes, and calls tools step by step. After enabling it, Claude Opus 4 accuracy jumped from 49% to 74%, and Claude Opus 4.5 from 79.5% to 88.1%. The system uses BM25 for retrieval and falls back to substring matching if needed.