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 91 days of history · worst day 0%

91 days agonow

4.4%

Uptime 24h

4 of 91 checks

Tools

read from the server

1542 ms

Response time

average over 24h

open, no key

Access

streamable-http

JSONShelf does not always answer

Over the last week it answered 4.7% of our checks. We check every 15 minutes, so you hear about the next outage within the hour — not from your users.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 10 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add jsonshelf --transport http https://jsonshelf.vercel.app/mcp

Settings → Connectors → Add custom connector, then paste this address

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

{
  "servers": {
    "jsonshelf": {
      "type": "http",
      "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

URL	Transport	State	Latency	Checked
https://jsonshelf.vercel.app/mcp	streamable-http	answering	46 ms	10 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 4 of 91 checks got a reply (4.4%), average response time 1542 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 in the form 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 1542 ms on average, which is faster than 1% 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.