Your MCP server eats 55,000 tokens before your agent says a word -- I measured the real cost

The invisible bill I was debugging why my Claude Code sessions felt sluggish after connecting a few MCP servers. Token usage was through the roof -- but I hadn't even asked the agent to do anything yet. I rewrote my prompts three times before I thought to check where the tokens were actually going. Turns out, the moment you connect an MCP server, every tool definition gets loaded into the context window. Names, descriptions, parameter schemas, enum values -- all of it, on every single conversati