io.github.jarbon/carbon
CARBON
Is the CARBON MCP server down? No. It answered initialize and tools/list in the probe of 2026-10-30.
AI testing harness with Jay: risk-based checks, bug investigation, and local evidence reports.
alive probed 2026-11-14 · unchanged since 2026-10-30
- Run it
- npx -y @testers-ai/carbon-mcp@1.32.22-free.17 (stdio, probed in a container with the network off)
- Host
- npmjs.com
- Reports itself as
- carbon-free 1.32.22-free.17
- Capabilities
- prompts, tools
- Instructions
- none
- Of a 1M window
- 0.1 % of a 1M context window
- Count
- 1.5k tokens in Claude Opus 5.5, exact, measured 2026-10-30. With the Claude Code prefix mcp__…__ on each tool name: 1.5k. The o200k_base estimate is 757. Counted again when the tool definitions change. Method.
- Repository
- https://github.com/jarbon/carbon-free
- Website
- https://testers.ai/carbon/
- Registry
- active, updated 2026-10-22 · registry entry
- Changes
- 2 recorded, reachable in 2 of them. A row is added when the result, the tool count or the cost changes.
Most expensive tools
The Claude column scales the o200k estimate of each tool by this server's ratio of exact to estimate, 1.94×.
| Tool | ≈ Claude tokens | o200k estimate | Share of this server |
|---|---|---|---|
| carbon_update | 585 | 301 | 40 % |
| carbon_start | 259 | 133 | 18 % |
| carbon_demo | 189 | 97 | 13 % |
| carbon_settings | 169 | 87 | 11 % |
| carbon_report | 148 | 76 | 10 % |
Compare this server with others.
More servers
Other registry entries on npmjs.com, the ones next to this name; all of them.
- io.github.janmalmstrom/lupaph-mcp · alive
- io.github.jannks/handbook · alive
- md-vision io.github.japlete/md-vision · needs args
- Home Assistant MCP Server io.github.jarahkon/hass-mcp-server · alive
- io.github.jaredco-ai/weather-mcp-server · no executable
- io.github.jaredhobbs/cronalert · alive
- io.github.jarekpiot/provenonce · alive
- io.github.jarod-vyent/xrpl-identity-mcp · alive
Servers that mention carbon.
- WattScope au.com.wattscope/wattscope · needs auth
- com.greencalculus/api · alive
- HasData Google Flights com.hasdata/google-flights · alive
- UK Environmental Intelligence MCP Server from MCPBundles com.mcpbundles/uk-environmental-intelligence · needs auth
- Trade & Logistics Evidence com.timzinin.api/trade-logistics · alive
- com.voltcast/voltcast · alive
- de.carbon-cashmere.api/crypto-intelligence · alive
- EcoCarbonWiki dev.carbonitex.ecogame/ecocarbonwiki · alive
History
We add a row when the result changes. A server with no change keeps its last row.
| Probed | Result | Init | Tools | Claude | o200k |
|---|---|---|---|---|---|
| 2026-10-30 07:49 | alive | 143 ms | 6 | 1.5k | 757 |
| 2026-10-23 06:51 | alive | 118 ms | 6 | 757 |
Badge for the README
The result of the latest probe, the tool count and the token cost. The feed has an entry for every probe that changed them.
A mail when this server changes
Stops answering, comes back, tool set or cost changes. One confirmation mail first, a stop link in every mail.
For the publisher
- The server answers initialize and tools/list. Nothing to fix.