japan-transfer-mcp
Version:
Model Context Protocol (MCP) server for J-Route Planner
208 lines (207 loc) • 9.92 kB
JavaScript
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from 'zod';
import { countTokens } from 'gpt-tokenizer';
import { pathToFileURL } from 'url';
import { fetchSuggest, fetchRouteSearch } from './fetcher.js';
import { parseRouteSearchResult } from './parser.js';
import { formatRouteSearchResponse } from './formatter.js';
const server = new McpServer({
name: "japan-transfer-mcp",
version: "0.0.6"
});
server.registerTool("search_station_by_name", {
title: "Search for stations by name",
description: "Search for stations by name",
inputSchema: {
query: z.string().describe("The name of the station to search for (must be in Japanese)"),
maxTokens: z.number().optional().describe("The maximum number of tokens to return"),
onlyName: z.boolean().optional().describe("Whether to only return the name of the station. If you do not need detailed information, it is generally recommended to set this to true."),
}
}, async ({ query, maxTokens, onlyName }) => {
try {
const response = await fetchSuggest({
query,
format: "json",
});
const railwayPlaces = response.R?.map((place) => {
if (onlyName) {
return place.poiName;
}
// placeの中身を自然な日本語文章で展開し、citycodeも含めて変数を埋め込む
// 例: "東京駅（東京都千代田区, citycode: 13101, 緯度: 35.681167, 経度: 139.767125, よみ: とうきょうえき）"
return `${place.poiName}（${place.prefName}${place.cityName ? place.cityName : ''}, citycode: ${place.cityCode ?? '不明'}, 緯度: ${place.location.lat}, 経度: ${place.location.lon}, よみ: ${place.poiYomi}）`;
});
const busPlaces = response.B?.map((place) => {
if (onlyName) {
return place.poiName;
}
return `${place.poiName}（${place.prefName}${place.cityName ? place.cityName : ''}, citycode: ${place.cityCode ?? '不明'}, 緯度: ${place.location.lat}, 経度: ${place.location.lon}, よみ: ${place.poiYomi}）`;
});
const spots = response.S?.map((place) => {
if (onlyName) {
return place.poiName;
}
return `${place.poiName}（${place.prefName}${place.cityName ? place.cityName : ''}${place.address ? ' ' + place.address : ''}, citycode: ${place.cityCode ?? '不明'}, 緯度: ${place.location.lat}, 経度: ${place.location.lon}, よみ: ${place.poiYomi}）`;
});
// railwayPlaces, busPlaces, spots を順に交互に配列化（R1,B1,S1,R2,B2,S2,...のような感じで）
const maxLen = Math.max(railwayPlaces ? railwayPlaces.length : 0, busPlaces ? busPlaces.length : 0, spots ? spots.length : 0);
const merged = [];
for (let i = 0; i < maxLen; i++) {
if (railwayPlaces && railwayPlaces[i] !== undefined)
merged.push(railwayPlaces[i]);
if (busPlaces && busPlaces[i] !== undefined)
merged.push(busPlaces[i]);
if (spots && spots[i] !== undefined)
merged.push(spots[i]);
}
// merged配列を上から順に,区切りで連結し、maxTokensの範囲内で切り詰める
// maxTokensが未指定の場合は全て連結
let result = "";
let tokenCount = 0;
let max = typeof maxTokens === "number" ? maxTokens : Infinity;
for (let i = 0; i < merged.length; i++) {
const next = (result ? "," : "") + merged[i];
const newTokenCount = countTokens(result + next);
if (newTokenCount > max)
break;
result += (result ? "," : "") + merged[i];
tokenCount = newTokenCount;
}
return {
content: [{
type: "text",
text: result
}]
};
}
catch (error) {
return {
content: [{
type: "text",
text: `Contact retrieval error: ${error instanceof Error ? error.message : String(error)}`
}],
isError: true
};
}
});
server.registerTool("search_route_by_station_name", {
title: "Search for routes by station name",
description: "Search for routes by station name",
inputSchema: {
from: z.string().describe("The name of the departure station. The value must be a name obtained from search_station_by_name."),
to: z.string().describe("The name of the arrival station. The value must be a name obtained from search_station_by_name."),
datetimeType: z.enum(["departure", "arrival", "first", "last"]).describe("The type of datetime to use for the search"),
datetime: z.string().optional().describe("The datetime to use for the search. Format: YYYY-MM-DD HH:MM:SS. If not provided, the current time in Japan will be used."),
maxTokens: z.number().optional().describe("The maximum number of tokens to return"),
},
}, async ({ from, to, datetimeType, datetime, maxTokens }) => {
try {
if (!datetime) {
// 日本の時刻（Asia/Tokyo）でISO形式（YYYY-MM-DD HH:MM:SS）にする
const now = new Date();
const jpNow = new Date(now.toLocaleString("ja-JP", { timeZone: "Asia/Tokyo" }));
const pad = (n) => n.toString().padStart(2, "0");
datetime = `${jpNow.getFullYear()}-${pad(jpNow.getMonth() + 1)}-${pad(jpNow.getDate())} ${pad(jpNow.getHours())}:${pad(jpNow.getMinutes())}:${pad(jpNow.getSeconds())}`;
}
// 日時の解析
const datePart = datetime.split(" ")[0];
const timePart = datetime.split(" ")[1];
const [year, month, day] = datePart.split("-").map(Number);
const [hour, minute] = timePart.split(":").map(Number);
// 駅タイプの判定（簡単な判定）
const isFromBusStop = from.includes("〔") || from.includes("［");
const isToBusStop = to.includes("〔") || to.includes("［");
const response = await fetchRouteSearch({
eki1: from,
eki2: to,
Dyy: year,
Dmm: month,
Ddd: day,
Dhh: hour,
Dmn1: Math.floor(minute / 10), // 分の10の位
Dmn2: minute % 10, // 分の1の位
Cway: (() => {
switch (datetimeType) {
case "departure":
return 0;
case "arrival":
return 1;
case "first":
return 2;
case "last":
return 3;
default:
return 0;
}
})(),
// デフォルト値を補完
via_on: -1, // 経由駅なし
Cfp: 1, // ICカード利用料金
Czu: 2, // ジパング倶楽部
C7: 1, // 通勤定期
C2: 0, // 飛行機利用: おまかせ
C3: 0, // 高速バス利用: おまかせ
C1: 0, // 有料特急: おまかせ
cartaxy: 1, // 車・タクシー検索: 有効
bikeshare: 1, // シェアサイクル検索: 有効
sort: "time", // 到着が早い・出発が遅い順
C4: 5, // 座席種別: おまかせ
C5: 0, // 優先列車: のぞみ優先
C6: 2, // 乗換時間: 標準
S: "検索", // 検索ボタン
Cmap1: "", // UI関連
rf: "nr", // リファラ
pg: 0, // ページ番号
eok1: isFromBusStop ? "B-" : "R-", // 駅1: 鉄道駅またはバス停
eok2: isToBusStop ? "B-" : "R-", // 駅2: 鉄道駅またはバス停
Csg: 1 // 検索開始フラグ
});
// HTMLレスポンスを解析
const parsedResult = parseRouteSearchResult(response.data);
// 自然な文章でレスポンスを構築
let resultText = formatRouteSearchResponse(parsedResult, response.url, from, to, datetime);
// maxTokensによる制限
if (maxTokens) {
const tokenCount = countTokens(resultText);
if (tokenCount > maxTokens) {
// トークン数が制限を超える場合は、ルートの数を減らす
const limitedResult = {
...parsedResult,
routes: parsedResult.routes.slice(0, Math.max(1, Math.floor(parsedResult.routes.length * maxTokens / tokenCount)))
};
resultText = formatRouteSearchResponse(limitedResult, response.url, from, to, datetime);
}
}
return {
content: [{
type: "text",
text: resultText
}]
};
}
catch (error) {
return {
content: [{
type: "text",
text: `Route search error: ${error instanceof Error ? error.message : String(error)}`
}],
isError: true
};
}
});
// メインモジュールとして実行された場合のみconnectする。
const currentFileUrl = import.meta.url;
try {
const scriptFileUrl = pathToFileURL(process.argv[1]).href;
if (currentFileUrl === scriptFileUrl) {
const transport = new StdioServerTransport();
await server.connect(transport);
}
}
catch (error) {
// pathToFileURLが失敗した場合（引数がundefinedなど）は何もしない
// これにより、ライブラリとしてimportされた場合と同じ動作になる
}
export default server;