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Your MCP Tool List Costs $6.50/Month in Pure Waste — Here's the Fix

#mcp #ai #devtools #claude

Your MCP Tool List Costs $6.50/Month in Pure Waste — Here's the Fix

Every time you open a new session, your client re-bills you for the same tool manifest.

Full disclosure: I'm one of the maintainers of mcptoon. Every number below comes from a real benchmark (tiktoken cl100k_base), not a pitch deck.

The invisible bill that recurs every session

Anyone using Claude, Cursor, or any agent has felt it: more tools installed → conversations get pricier, slower, and fill up faster.

The problem isn't the tools. It's a line item almost nobody looks at — the tool manifest.

Every session, the client stuffs the complete manifest of every MCP server into context. In JSON, that list runs tens of thousands of tokens — and it gets re-billed every time you start a new session.

Measured on 255 tools / 50 servers:

Raw JSON manifest Tokens What it means
Full manifest 71,929 Recharged every session
In money ≈ $0.22/session @ $3/M input
30 sessions/day ≈ $6.50/month Pure manifest tax — zero tool calls

Pure waste. Your agent isn't using those 70k tokens; it just has to "read the whole name list" before it can start.

A name directory that costs 124 tokens

mcptoon slims that 70k-token JSON into a plain name directory. Same config:

Format Tokens Savings
Raw JSON 71,929 —
--slim (trimmed params) 8,282 −88.5%
--compact (names only) 124 −99.8%

Measured on a real 255-tool / 50-server config (tiktoken cl100k_base). Reproduce on your machine: mcptoon manifest --compact --tokens.

Verify it yourself in 30 seconds 

pip install mcptoon && mcptoon demo
Enter fullscreen mode Exit fullscreen mode

mcptoon demo prints the token numbers for JSON vs. mcptoon format, using your own servers, on your own box.

Why saving tokens is worth it

  1. Long conversations stop filling up so fast. Room a 70k-token manifest used = several more rounds.
  2. Multiple agents, one source of truth. One config (~/.mcptoon/config.json) for all clients; sync pushes to all in seconds.
  3. Install more tools without the fear. Context bloat fears disappear once the list is slim.

Zero dependencies (pure Python stdlib, ~250KB), open source (Apache-2.0), Windows / macOS / Linux, blocks injection and credential leaks.

Asking "what tools do I have?" shouldn't cost 70,000 tokens.

Benchmark: projects/mcptoon/assets/benchmark_tiktoken.json (tiktoken cl100k_base)
GitHub: github.com/activeing123/mcptoon
Install: pip install mcptoon && mcptoon demo

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