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JSONShelf MCP Server

by walkojas-boop Your server? Claim it
not responding

JSONShelf is listed as active in the registry but did not answer our last check. It exposes 4 tools.

Deterministic JSON repair, validate, example-gen, schema-coerce for agents. Zero LLM, sub-10ms.

The linked repository no longer exists on GitHub — it was deleted or made private.

Uptime history 47 days of history · worst day 0%
47 days agonow
16.5%
Uptime 24h
15 of 91 checks
4
Tools
read from the server
1161 ms
Response time
average over 24h
open, no key
Access
streamable-http

JSONShelf does not always answer

Over the last week it answered 16.6% of our checks. We check every 15 minutes, so you hear about the next outage within the hour — not from your users.

Three servers free · no card

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 11 min ago.

run in your terminal
claude mcp add jsonshelf --transport http https://jsonshelf.vercel.app/mcp
~/Library/Application Support/Claude/claude_desktop_config.json
{
  "mcpServers": {
    "jsonshelf": {
      "url": "https://jsonshelf.vercel.app/mcp"
    }
  }
}
~/.codex/config.toml
[mcp_servers.jsonshelf]
url = "https://jsonshelf.vercel.app/mcp"
.cursor/mcp.json
{
  "mcpServers": {
    "jsonshelf": {
      "url": "https://jsonshelf.vercel.app/mcp"
    }
  }
}
.vscode/mcp.json
{
  "mcpServers": {
    "jsonshelf": {
      "url": "https://jsonshelf.vercel.app/mcp"
    }
  }
}

Available tools 4

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

jsonshelf
jsonshelf_coerce
Soft-cast values to match a schema (string "42" → 42 for integer fields, etc.).
jsonshelf_example
Generate a minimal valid example matching a JSON schema.
jsonshelf_repair
Repair malformed JSON. Returns valid JSON plus a diff of what was fixed.
jsonshelf_validate
Validate JSON against a schema. Returns structured errors with JSON Pointer paths and remedies.

Endpoints

URLTransportStateLatencyChecked
https://jsonshelf.vercel.app/mcp streamable-http answering 44 ms 11 min ago

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JSONShelf — questions

Answers built from our own checks of this server.

What can JSONShelf do?
It exposes 4 tools, read directly from the server on our last check. Among them: jsonshelf_coerce, jsonshelf_example, jsonshelf_repair, jsonshelf_validate. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →
Is JSONShelf working right now?
We send a real MCP handshake every 15 minutes. Over the last 24 hours 15 of 91 checks got a reply (16.5%), average response time 1161 ms. The bar chart above shows every period we have measured.
Is JSONShelf still maintained?
The linked repository no longer exists on GitHub — it was deleted or made private. We show this because it changes what you can expect: an unmaintained server may keep answering for months and then stop without warning.
The registry lists JSONShelf as active — why does it not respond?
The official MCP registry stores what the author submitted; it does not verify that the server still runs. We check the endpoint ourselves, and this one does not answer. Catalogues that copy the registry without checking will show it as working.
How do I connect JSONShelf?
Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.
Does JSONShelf need an API key?
No. JSONShelf completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 4 of them are readable on this page. This is what we observed, not what the docs claim.
How fast is JSONShelf?
It answers our handshake in 1161 ms on average, which is faster than 5% of all working MCP servers we measure. That is on the slow side — worth knowing if the tool sits inside an interactive loop. The comparison comes from our own checks across the whole registry, every 15 minutes.