io.github.rog0x/json

mcp-json-tools

Is the io.github.rog0x/json MCP server down? No. It answered initialize and tools/list in the probe of 2026-10-30.

JSON/YAML/CSV validate, diff, transform for AI agents

alive probed 2026-11-14 · unchanged since 2026-10-30

7tools

1.5ktokens in Claude Opus 5.5

0.8 %of Claude's 200k window

0.6×the median server

394 msto initialize

11 msto list tools

Run it: npx -y @rog0x/mcp-json-tools@1.0.1 (stdio, probed in a container with the network off)
Host: npmjs.com
Reports itself as: mcp-json-tools 1.0.0
Capabilities: tools
Instructions: none
Of a 1M window: 0.2 % of a 1M context window
Count: 1.5k tokens in Claude Opus 5.5, exact, measured 2026-10-16. With the Claude Code prefix mcp__…__ on each tool name: 1.6k. The o200k_base estimate is 831. Counted again when the tool definitions change. Method.
Repository: https://github.com/rog0x/mcp-json-tools
Registry: active, updated 2026-03-22 · registry entry

Most expensive tools

The Claude column scales the o200k estimate of each tool by this server's ratio of exact to estimate, 1.83×.

Tool	≈ Claude tokens	o200k estimate	Share of this server
json_transform	382	209	25 %
csv_to_json	256	140	17 %
json_to_csv	210	115	14 %
json_validate	192	105	13 %
json_diff	173	95	11 %

Other registry entries on npmjs.com, the ones next to this name; all of them.

Servers that mention json.

The result of the latest probe, the tool count and the token cost. The feed has an entry for every probe that changed them.

Stops answering, comes back, tool set or cost changes. One confirmation mail first, a stop link in every mail.