io.github.mrfentmen/jsonc-mcp

jsonc-mcp

Is the io.github.mrfentmen/jsonc-mcp MCP server down? No. It answered initialize and tools/list in the probe of 2026-10-29.

Work with JSONC offline: strip comments and trailing commas, parse to JSON and locate errors

alive probed 2026-11-14 · unchanged since 2026-10-29

3tools

520tokens in Claude Opus 5.5

0.3 %of Claude's 200k window

0.2×the median server

250 msto initialize

6 msto list tools

Run it: npx -y @mrfentmen/jsonc-mcp@1.0.1 (stdio, probed in a container with the network off)
Host: npmjs.com
Reports itself as: jsonc-mcp 1.0.0
Capabilities: tools
Instructions: none
Of a 1M window: <0.1 % of a 1M context window
Count: 520 tokens in Claude Opus 5.5, exact, measured 2026-10-29. With the Claude Code prefix mcp__…__ on each tool name: 559. The o200k_base estimate is 285. Counted again when the tool definitions change. Method.
Repository: https://github.com/mrfentmen/awesome-servers
Registry: active, updated 2026-10-28 · registry entry

Most expensive tools

The Claude column scales the o200k estimate of each tool by this server's ratio of exact to estimate, 1.82×.

Tool	≈ Claude tokens	o200k estimate	Share of this server
parse_jsonc	193	106	37 %
strip_jsonc	179	98	34 %
validate_jsonc	148	81	28 %

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

Servers that mention jsonc or comments or trailing.

io.mcpcentral/jsoncanvas · needs auth
ai.smithery/BigVik193-reddit-user-mcp · not found
Supercut ai.supercut/mcp · needs auth
FRTracker — Federal Regulatory Research app.frtracker/regulatory-research · needs auth
Kangram app.kangram/kangram · alive
Kanera app.kanera/mcp · needs auth
app.repage/repage · needs auth
ShareMyPage app.sharemypage/sharemypage · needs auth

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.