io.github.ceedot-rock/json-chamber-mcp
Chamber
Two-key JSON seal/open. Cloak needs a live license. Open is keys-only.
alive probed 2026-10-15
5tools
521tokens in Claude Opus 5.5
591tokens in Claude Code
0.3 %of a 200k context window
278o200k_base estimate
376 msto initialize
9 msto list tools
- Run it
- npx -y json-chamber-mcp@1.2.0 (stdio, probed in a container with the network off)
- Host
- npmjs.com
- Reports itself as
- json-chamber-mcp 1.2.0
- Capabilities
- tools
- Instructions
- none
- Claude count
- Claude Opus 5.5, measured 2026-10-15. Counted again when the tool definitions change. Method.
- Repository
- https://github.com/ceedot-rock/json-chamber-mcp
- Website
- https://www.slidphilabs.com/chamber
- Registry
- active, updated 2026-09-14 · registry entry
- Reachable
- 1 of the last 1 probe
Most expensive tools
| Tool | Tokens (o200k) | Share of this server |
|---|---|---|
| chamber_cloak | 75 | 27 % |
| benefit_check | 75 | 27 % |
| chamber_open | 55 | 20 % |
| chamber_info | 40 | 14 % |
| chamber_status | 33 | 12 % |
Badge and feed
[](https://mcpcost.ulehla.dev/s/io.github.ceedot-rock/json-chamber-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.