io.github.mrfentmen/isbndb-mcp

isbndb-mcp

ISBNdb books: lookup by ISBN, search, batch lookup. Needs API key.

alive probed 2026-10-14

3tools

425tokens in Claude Opus 5.5

464tokens in Claude Code

0.2 %of a 200k context window

225o200k_base estimate

385 msto initialize

8 msto list tools

Run it: npx -y isbndb-mcp@1.0.1 (stdio, probed in a container with the network off)
Host: npmjs.com
Reports itself as: isbndb-mcp 1.0.0
Capabilities: tools
Instructions: none
Claude count: Claude Opus 5.5, measured 2026-10-14. Counted again when the tool definitions change. Method.
Repository: https://github.com/mrfentmen/premium-mcps
Registry: active, updated 2026-10-01 · registry entry
Reachable: 1 of the last 1 probe

Most expensive tools

Tool	Tokens (o200k)	Share of this server
search_books	82	36 %
get_book	74	33 %
get_books_batch	69	31 %

Badge and feed

[![mcpcost](https://mcpcost.ulehla.dev/badge/io.github.mrfentmen/isbndb-mcp.svg)](https://mcpcost.ulehla.dev/s/io.github.mrfentmen/isbndb-mcp)

An entry for every probe that changed the result, the tool count or the token cost: Atom feed. Add it to a feed reader or a Slack RSS app to hear when the server stops answering or its tool set grows.