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JSONShelf

https://jsonshelf.vercel.app/mcp

● healthy

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

Transport

streamable-http

Auth

—

Cost

—

Protocol revision

2024-11-05

negotiated, not declared

MCP readiness

B · 80/100

Readiness is how fully this listing follows its protocol and how it behaved in our probes over 30 days. It is shown for reference and does not move it in search. Search order and leaderboards use the separate quality grade (here C+, 70.0/100), which weighs availability, conformance, p95 speed and descriptor. How the two differ

Valid MCP handshake	10/10	initialize and tools/list both answered.
Live MCP endpoint	25/25	Endpoint answers the MCP initialize handshake (2113 ms).
Protocol revision	5/10	Speaks MCP 2024-11-05, 4 revision(s) behind 2026-07-28.
Signed descriptor	n/a	No MCP standard defines a signed server descriptor.
Uptime (30 days)	15/15	30/30 probes succeeded over 30 days (100%).
Tool declaration	10/10	Lists 4 tool(s) with descriptions.
Verified identity	7/10	Namespace verified by the official MCP Registry (GitHub or DNS proof at publish time).
Freshness + modern flags	0/5	not seen in a source for over 30 days.
Auth declaration	0/5	How to authenticate is not stated.

Applicable criteria total 90 points, scaled to 100.

Responsiveness: Responsive (2113 ms; bands ≤2.5 s, ≤5 s, ≤8 s, slower; penalty only).

Measured 2026-11-11.

Nine criteria, the same as the A2A readiness score, read from our daily MCP probe (initialize + tools/list) and 30-day probe history. No MCP standard defines a signed server descriptor, so that criterion is n/a and the other 90 points are scaled to 100. Grades: A>=90, B>=75, C>=60, D>=40, F<40. Display only: search order uses the quality grade.

Compared with peers

Against 53,039 reachable MCP servers in our daily snapshot (2026-11-12 06:46 UTC). Display only; it does not change search order.

Readiness: Higher than 45% of peers; This listing 80 · peer median 81
Latency: Faster than 56% of peers; This listing 282 ms · peer median 326 ms

Where it loses the most points, and how to win them back

Protocol revision −5 — Support the current protocol revision.
Now: Speaks MCP 2024-11-05, 4 revision(s) behind 2026-07-28.
Freshness + modern flags −5 — Keep the listing current in the registry or source it comes from.
Now: not seen in a source for over 30 days.
Auth declaration −5 — State how to authenticate (an auth scheme, or that none is needed).
Now: How to authenticate is not stated.

How many agent tools actually work · All statistics

Listed in

Directories this entry was found in.

chiark since 2026-06-04 ↗ mcp-registry since 2026-08-18 wellknown since 2026-09-23 ↗ agenstry since 2026-10-22 ↗

How to connect

MCP endpoint (streamable-http)

https://jsonshelf.vercel.app/mcp

JSON-RPC initialize probe

curl -X POST https://jsonshelf.vercel.app/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{}}'

Homepage

https://jsonshelf.vercel.app/

Source code

https://github.com/walkojas-boop/jsonshelf