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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

MahjongHandbook — American NMJL, MCR & Riichi Mahjong Scoring Rules Engine

By mahjonghandbook.com Verified namespace

Query American NMJL, Chinese Official MCR (81 Fan) & Japanese Riichi Mahjong scoring rules.

WebsiteSource code
Connect to MahjongHandbook — American NMJL, MCR & Riichi Mahjong Scoring Rules Engine
Checks passed
15 / 22

0 failed · 7 not measured

Median response
70 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
4

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 71 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name com.mahjonghandbook/mcp.

  • Pass
    Lists tools

    tools/list returned 4 tools.

  • Pass
    Current protocol

    Negotiated 2025-06-18. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 70 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 71 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    4 of 4 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T06:17:03.114928Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using MahjongHandbook — American NMJL, MCR & Riichi Mahjong Scoring Rules Engine

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http mahjonghandbook-american-nmjl-mcr-riichi-mahjong-scoring-rules-engine https://mahjonghandbook.com/api/mcp

Capabilities

Tools 4

check_nmjl_joker_legality

Validate whether an American Mahjong Joker tile can legally substitute inside a specific meld size (1 to 6 tiles) and retrieve exposed Joker live-turn swap rules.

Discovered
check_riichi_furiten_and_yaku

Evaluate Japanese Riichi Mahjong discard/temporary Furiten Ron restrictions and verify whether a hand satisfies the mandatory 1-Yaku win condition independent of Dora.

Discovered
lookup_american_charleston_sequence

Retrieve exact pre-game tile passing directions (Right, Across, Left), blind pass rules, and Courtesy Pass negotiation steps prior to the first discard in American Mahjong.

Discovered
lookup_mahjong_scoring_rules

Compare high-level regional ruleset structures (tile deck size 136 vs 144 vs 152, hand length, and minimum Fan/point entry thresholds) across American, Chinese MCR, Japanese Riichi, and Hong Kong Mahjong. Do not use for Charleston passing steps, NMJL Joker meld legality, or Riichi Furiten checks.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected71 ms4
Connected69 ms4

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