Dev Tools · 2h ago
Anthropic's Tool Search Fix Reveals MCP's Context Bloat Problem
Anthropic released Tool Search on November 24th, allowing lazy loading of tool schemas in MCP. Accuracy jumped from 49% to 74% on Opus 4 and from 79.5% to 88.1% on Opus 4.5 simply by not loading tool definitions upfront. The feature is an implicit admission that MCP's context overhead was tanking performance by up to 25 percentage points.
Meridian48 take
Tool Search is a band-aid, not a cure—MCP's architecture still burns tokens on idle schemas, and the community is already building workarounds like mcporter that ditch the protocol entirely.
anthropicmcp-context-overhead