TL;DR: Swapping grep for MCP retrieval tools cost my coding agent 4. 1x more tokens on a 33-file repo, and saved 86% on a 249-file one. Same model, same tasks, opposite sign.
Source: [Dev.to](https://dev.to/pranav_raj_dae81effb8b57d/mcp-retrieval-cost-4x-more-tokens-than-grep-until-repo-size-flipped-it-5cfj)