io.github.slettmayer/calc-mcp-server
Calculator
Exact arithmetic: one calculator tool over an AST allowlist, with integers exact at any size.
alive probed 2026-10-15
1tools
237tokens in Claude Opus 5.5
250tokens in Claude Code
0.1 %of a 200k context window
148o200k_base estimate
3.0 sto initialize
6 msto list tools
- Run it
- uvx calc-mcp-server==0.1.9 (stdio, probed in a container with the network off)
- Host
- pypi.org
- Reports itself as
- calculator 0.1.9
- Capabilities
- prompts, resources, tools
- Instructions
- 350 characters
- Claude count
- Claude Opus 5.5, measured 2026-10-15. Counted again when the tool definitions change. Method.
- Repository
- https://github.com/slettmayer/calc-mcp-server
- Website
- https://github.com/slettmayer/calc-mcp-server
- Registry
- active, updated 2026-09-17 · registry entry
- Reachable
- 1 of the last 1 probe
Most expensive tools
| Tool | Tokens (o200k) | Share of this server |
|---|---|---|
| calculate | 148 | 100 % |
Badge and feed
[](https://mcpcost.ulehla.dev/s/io.github.slettmayer/calc-mcp-server)
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.