Japan Data MCP
NPM · @MAMETA/JAPAN-DATA-MCP · SCANNED SEP 20
30 tools for Japanese data: address, furigana, transit, Diet, holidays, weather, corporate registry
Available components
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security99
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- 34 of 127 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency45
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- Clear OSI-approved license (Apache-2.0).Pass
- Actively maintained (last published 74 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability77
- AI-judged instruction clarity (good).Pass
- Tool/resource definitions use about 2140 tokens (~71/item across 30 items; 30 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management87
- Stability observed for 26 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 30 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 31 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
How do I install the Japan Data MCP server?
Japan Data MCP runs locally as an npm package, launched with npx -y @mameta/japan-data-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · @mameta/japan-data-mcp
claude mcp add mameta29-japan-data-mcp -- npx -y @mameta/japan-data-mcp
{
"mcpServers": {
"mameta29-japan-data-mcp": {
"command": "npx",
"args": [
"-y",
"@mameta/japan-data-mcp"
]
}
}
} {
"servers": {
"mameta29-japan-data-mcp": {
"command": "npx",
"args": [
"-y",
"@mameta/japan-data-mcp"
]
}
}
} codex mcp add mameta29-japan-data-mcp -- npx -y @mameta/japan-data-mcp
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"mameta29-japan-data-mcp": {
"type": "local",
"command": [
"npx",
"-y",
"@mameta/japan-data-mcp"
],
"enabled": true
}
}
} openclaw mcp add mameta29-japan-data-mcp --command npx --arg -y --arg @mameta/japan-data-mcp
mcp_servers:
mameta29-japan-data-mcp:
command: "npx"
args: ["-y", "@mameta/japan-data-mcp"] {
"McpServers": {
"mameta29-japan-data-mcp": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@mameta/japan-data-mcp"
]
}
}
} assistant mcp add mameta29-japan-data-mcp -t stdio -c npx -a -y @mameta/japan-data-mcp
{
"mcpServers": {
"mameta29-japan-data-mcp": {
"command": "npx",
"args": [
"-y",
"@mameta/japan-data-mcp"
]
}
}
} Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 20 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 18 Sept 26 −3
- Stability: pass → 0.80 functional
- 17 Sept 26 +1
- Stability: 0.97 → pass security
- 15 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
- 13 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 11 Sept 26 −3
- Stability: pass → 0.80 functional
- 10 Sept 26 +1
- Stability: 0.97 → pass security
- 8 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 20 Sept 2026 · Analysed npm/@mameta/japan-data-mcp@1.1.0
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Dependencies 127 packages
| Packages resolved | 127 |
|---|---|
| Stale | 34 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
address_geocode ~46
Geocode a Japanese address to WGS84 lat/lng coordinates, with a granularity level and confidence score. Japan-only.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | yes | A Japanese address string. |
No output schema declared.
No examples provided.
address_normalize ~67
Normalize a Japanese address into clean prefecture/city/town/chome components, fixing fullwidth/halfwidth and old-form kanji, and resolving the postal code. Returns a 0-1 confidence score.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | yes | A Japanese address string, any common notation. |
No output schema declared.
No examples provided.
address_parse ~53
Extract a fully structured Japanese address — including building name, room number, and addressee — from free-form, OCR, or voice-transcribed text.
| Name | Type | Req | Description |
|---|---|---|---|
| text | string | yes | Free-form text containing a Japanese address. |
No output schema declared.
No examples provided.
address_postal_code ~63
Look up Japanese address candidates for a 7-digit postal code (郵便番号), backed by Japan Post KEN_ALL data.
| Name | Type | Req | Description |
|---|---|---|---|
| zip | string | yes | A 7-digit Japanese postal code; hyphen optional (e.g. 100-0014). |
No output schema declared.
No examples provided.
address_reverse_geocode ~51
Reverse-geocode WGS84 lat/lng coordinates within Japan to a normalized address.
| Name | Type | Req | Description |
|---|---|---|---|
| lat | number | yes | Latitude (WGS84). |
| lng | number | yes | Longitude (WGS84). |
No output schema declared.
No examples provided.
diet_member ~44
Full profile of a Japanese National Diet member by canonical id — party, constituency, committees, positions.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Canonical member id (from diet_members_search). |
No output schema declared.
No examples provided.
diet_members_search ~125
Search current Japanese National Diet members by name (kanji/kana/romaji), party, house, or constituency.
| Name | Type | Req | Description |
|---|---|---|---|
| active_only | boolean | – | Restrict to currently-serving members. |
| constituency | string | – | Constituency. |
| house | string | – | Chamber: shugiin (House of Representatives) or sangiin (House of Councillors). |
| limit | number | – | Max results, 1-100. Default 20. |
| party | string | – | Party name. |
| q | string | – | Member name (kanji, kana, or romaji). |
No output schema declared.
No examples provided.
diet_minutes_search ~161
Full-text search the official Japanese Diet proceedings archive (国会会議録), filterable by date, house, committee, and speaker.
| Name | Type | Req | Description |
|---|---|---|---|
| committee | string | – | Committee name, e.g. 財務金融委員会. |
| from_date | string | – | Start date, YYYY-MM-DD. |
| house | string | – | Restrict to one chamber: shugiin or sangiin. |
| limit | number | – | Max results, 1-100. Default 20. |
| offset | number | – | 1-based result offset for pagination. Default 1. |
| query | string | yes | Search keyword. |
| speaker | string | – | Restrict to a speaker's remarks. |
| to_date | string | – | End date, YYYY-MM-DD. |
No output schema declared.
No examples provided.
diet_minutes_summarize ~69
AI-generated (Claude) summary of a Japanese Diet committee meeting transcript — key topics and quotes, in Japanese and/or English.
| Name | Type | Req | Description |
|---|---|---|---|
| language | string | – | Summary language. |
| meeting_id | string | yes | Meeting id from diet_minutes_search. |
| summary_length | string | – | Summary length. |
No output schema declared.
No examples provided.
diet_topic_track ~114
Track how a policy topic has been discussed across recent Japanese Diet meetings: a dated timeline, key actors, and an AI-written policy-direction narrative.
| Name | Type | Req | Description |
|---|---|---|---|
| from_date | string | yes | Start date, YYYY-MM-DD. Required. |
| language | string | – | Narrative language. Default ja. |
| max_meetings | number | – | Max meetings to analyze, 1-20. Default 10. |
| to_date | string | yes | End date, YYYY-MM-DD. Required. |
| topic | string | yes | Policy topic. |
No output schema declared.
No examples provided.
furigana_classify ~49
Classify a Japanese string as person_name / company_name / place_name / general / mixed, with a probability and character-type breakdown.
| Name | Type | Req | Description |
|---|---|---|---|
| text | string | yes | Japanese text to classify. |
No output schema declared.
No examples provided.
furigana_convert ~59
Convert kanji-mixed Japanese text to hiragana, katakana, or romaji, with a per-token reading breakdown.
| Name | Type | Req | Description |
|---|---|---|---|
| text | string | yes | Japanese text to read. |
| to | string | – | Target script. Default hiragana. |
No output schema declared.
No examples provided.
furigana_name_readings ~63
List the possible readings of a Japanese name (person, company, or place), each with a probability — names are ambiguous without context.
| Name | Type | Req | Description |
|---|---|---|---|
| name | string | yes | A Japanese name. |
| name_type | string | – | Hint for the kind of name. |
No output schema declared.
No examples provided.
holiday_add_business_days ~67
Add (or subtract) a number of Japanese business days to a date, skipping weekends and public holidays.
| Name | Type | Req | Description |
|---|---|---|---|
| business_days | number | yes | Business days to add (-3650 to 3650); negative subtracts. |
| date | string | yes | Start date, YYYY-MM-DD. |
No output schema declared.
No examples provided.
holiday_business_days_between ~52
Count the Japanese business days between two dates (inclusive of neither endpoint by default).
| Name | Type | Req | Description |
|---|---|---|---|
| from | string | yes | Start date, YYYY-MM-DD. |
| to | string | yes | End date, YYYY-MM-DD. |
No output schema declared.
No examples provided.
holiday_is_holiday ~48
Classify a Japanese calendar date as a public holiday, weekend, or business day. Backed by official Cabinet Office data.
| Name | Type | Req | Description |
|---|---|---|---|
| date | string | yes | A date, YYYY-MM-DD. |
No output schema declared.
No examples provided.
holiday_list ~28
List all Japanese public holidays for a given year.
| Name | Type | Req | Description |
|---|---|---|---|
| year | number | yes | Four-digit year. |
No output schema declared.
No examples provided.
houjin_corporation ~48
Look up one Japanese corporation by its 13-digit corporate number (法人番号), against the National Tax Agency registry.
| Name | Type | Req | Description |
|---|---|---|---|
| number | string | yes | A 13-digit Japanese corporate number. |
No output schema declared.
No examples provided.
houjin_kyb_report ~153
One-call KYB report on a Japanese corporation: official registry record, lifecycle status (active/closed), kana + romaji name readings, machine-actionable risk flags, an English summary, and the dataset vintage. Accepts a 13-digit corporate number or a company name. Premium composite ($0.25) — replaces 3-4 separate lookups.
| Name | Type | Req | Description |
|---|---|---|---|
| city | string | – | Optional city/ward filter for name resolution. |
| corporate_number | string | – | 13-digit corporate number (法人番号). Either this or name is required. |
| name | string | – | Company trade name when the number is unknown. |
| prefecture | string | – | Optional prefecture filter for name resolution. |
No output schema declared.
No examples provided.
houjin_search ~108
Search the Japanese corporate registry by trade name and/or location. Matches Japanese and registered English names.
| Name | Type | Req | Description |
|---|---|---|---|
| city | string | – | City / ward substring. |
| corp_kind | string | – | 3-digit corporation-kind code (法人種別), e.g. 301 for 株式会社. |
| limit | number | – | Max results, 1-50. |
| name | string | yes | Trade name, partial match. |
| prefecture | string | – | Prefecture name or JIS code. |
No output schema declared.
No examples provided.
houjin_verify ~72
Name-match (名寄せ) a company name plus location against the Japanese corporate registry, returning the most likely corporate number with a confidence score. Closed/dissolved companies are reported as not verified.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | – | Company address, improves matching. |
| name | string | yes | Company name to verify. |
No output schema declared.
No examples provided.
transit_alternative_routes ~49
Suggest delay-aware alternative routes for Japanese train travel — ranked routes that avoid currently-disrupted lines.
| Name | Type | Req | Description |
|---|---|---|---|
| from | string | yes | Origin station name. |
| to | string | yes | Destination station name. |
No output schema declared.
No examples provided.
transit_line_disruptions ~42
Current service disruptions on a specific Japanese train line.
| Name | Type | Req | Description |
|---|---|---|---|
| line | string | yes | Line id from transit_lines (e.g. jr-east-yamanote). |
No output schema declared.
No examples provided.
transit_lines ~28
Directory of Japanese rail operators and their lines, with canonical ids. Use to discover valid line identifiers.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
transit_route_plan ~45
Plan a route between two Japanese train stations with transfers, duration, and fare.
| Name | Type | Req | Description |
|---|---|---|---|
| from | string | yes | Origin station name. |
| to | string | yes | Destination station name. |
No output schema declared.
No examples provided.
transit_station_status ~53
Real-time delay and operational status for a Japanese train station, per line, with a bilingual summary. Sourced from ODPT.
| Name | Type | Req | Description |
|---|---|---|---|
| name | string | yes | Station name (kanji, kana, or romaji). |
No output schema declared.
No examples provided.
transit_stations_search ~43
Fuzzy-search Japanese train stations by name (kanji, kana, or romaji).
| Name | Type | Req | Description |
|---|---|---|---|
| q | string | yes | Search query, at least 2 characters. |
No output schema declared.
No examples provided.
weather_areas ~24
List the valid JMA region codes and names accepted by the weather tools.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
weather_forecast ~56
Japanese weather forecast for a region — today's conditions, near-term outlook, and a 7-day forecast. Sourced from the JMA.
| Name | Type | Req | Description |
|---|---|---|---|
| area | string | yes | A JMA office code or a Japanese/English region name. |
No output schema declared.
No examples provided.
weather_warnings ~40
Active Japanese weather warnings and advisories for a region, from the JMA.
| Name | Type | Req | Description |
|---|---|---|---|
| area | string | yes | A JMA office code or region name. |
No output schema declared.
No examples provided.
What is the Japan Data MCP server?
Japan Data MCP is listed in the public MCP registry as io.github.Mameta29/japan-data-mcp. 30 tools for Japanese data: address, furigana, transit, Diet, holidays, weather, corporate registry. This page covers its npm package (@mameta/japan-data-mcp).
Is the Japan Data MCP server safe to use?
Japan Data MCP scores 83 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 20 September 2026. It declares no install or post-install scripts. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the Japan Data MCP server expose?
Japan Data MCP exposes 30 tools: address_normalize, address_geocode, address_reverse_geocode, address_postal_code, address_parse, and 25 more. Their descriptions and schemas cost roughly 1,920 tokens of context every time the server is loaded.
Is the Japan Data MCP server still maintained?
Japan Data MCP is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What licence is the Japan Data MCP server under?
Japan Data MCP declares the Apache-2.0 licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.