There are a lot of folks claiming “MCPs eat context” and that you should use CLIs instead, e.g. Gary Tan:
MCP sucks honestly
Garry Tan (@garrytan) March 12, 2026
It eats too much context window and you have to toggle it on and off and the auth sucks
I got sick of Claude in Chrome via MCP and vibe coded a CLI wrapper for Playwright tonight in 30 minutes only for my team to tell me Vercel already did it lmao
But it… https://t.co/fWGVqIHK3I
The problem isn’t MCP; it’s your agent’s harness.
MCP has nothing to do with your context window
The MCP protocol allows a server to expose tools, resources and prompts to a client. It says nothing about how a client is supposed to expose those things (or not) to an LLM.
How the client exposes these things to the LLM is entirely a client decision. And so much context is wasted because clients do stupid things like take the raw JSON output of an MCP server and feed it directly into the LLM’s context window.