eve-online-mcp

Instructions

Implementation Reference

• src/index.ts:298-321 (handler)

  The main handler function for the 'get-market-orders' tool. It constructs the ESI API endpoint for market orders in the specified region, optionally appends type_id filter, fetches the orders using makeESIRequest, filters by order_type (buy/sell/all), and returns the result as JSON text content.

    async ({ region_id, type_id, order_type }) => {
      let endpoint = `/markets/${region_id}/orders/`;
      if (type_id) {
        endpoint += `?type_id=${type_id}`;
      }
  
      const orders = await makeESIRequest<Array<MarketOrder>>(endpoint);
  
      const filteredOrders = orders.filter((order) => {
        if (order_type === "buy") return order.is_buy_order;
        if (order_type === "sell") return !order.is_buy_order;
        return true;
      });
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(filteredOrders, null, 2),
          },
        ],
      };
    }
  );

• src/index.ts:290-297 (schema)

  Zod input schema defining parameters for the tool: region_id (required number), type_id (optional number), order_type (enum ["buy","sell","all"] with default "all".

  {
    region_id: z.number().describe("Region ID to get market orders from"),
    type_id: z.number().optional().describe("Item type ID to filter orders"),
    order_type: z
      .enum(["buy", "sell", "all"])
      .default("all")
      .describe("Type of orders to retrieve"),
  },

• src/index.ts:287-321 (registration)

  Registration of the 'get-market-orders' tool on the MCP server, including name, description, input schema, and inline handler function.

  server.tool(
    "get-market-orders",
    "Get market orders from a specific region",
    {
      region_id: z.number().describe("Region ID to get market orders from"),
      type_id: z.number().optional().describe("Item type ID to filter orders"),
      order_type: z
        .enum(["buy", "sell", "all"])
        .default("all")
        .describe("Type of orders to retrieve"),
    },
    async ({ region_id, type_id, order_type }) => {
      let endpoint = `/markets/${region_id}/orders/`;
      if (type_id) {
        endpoint += `?type_id=${type_id}`;
      }
  
      const orders = await makeESIRequest<Array<MarketOrder>>(endpoint);
  
      const filteredOrders = orders.filter((order) => {
        if (order_type === "buy") return order.is_buy_order;
        if (order_type === "sell") return !order.is_buy_order;
        return true;
      });
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(filteredOrders, null, 2),
          },
        ],
      };
    }
  );

• src/index.ts:29-42 (schema)

  TypeScript interface defining the MarketOrder type used by the handler for typing the API response.

  interface MarketOrder {
    duration: number;
    is_buy_order: boolean;
    issued: string;
    location_id: number;
    min_volume: number;
    order_id: number;
    price: number;
    range: string;
    system_id: number;
    type_id: number;
    volume_remain: number;
    volume_total: number;
  }

• src/index.ts:222-256 (helper)

  Helper function used by the handler to make authenticated and rate-limited requests to the EVE ESI API.

  async function makeESIRequest<T>(endpoint: string, token?: string): Promise<T> {
    if (!checkRateLimit(endpoint)) {
      throw new Error("Rate limit exceeded. Please try again later.");
    }
  
    const headers: Record<string, string> = {
      "User-Agent": USER_AGENT,
      "Accept": "application/json",
    };
  
    if (token) {
      headers["Authorization"] = `Bearer ${token}`;
    }
  
    const response = await fetch(`${ESI_BASE_URL}${endpoint}`, { headers });
    updateRateLimit(endpoint, response.headers);
  
    if (!response.ok) {
      let errorMessage = `HTTP error! status: ${response.status}`;
      try {
        const errorData = await response.json() as ESIError;
        if (errorData.error) {
          errorMessage = `ESI Error: ${errorData.error}`;
          if (errorData.error_description) {
            errorMessage += ` - ${errorData.error_description}`;
          }
        }
      } catch {
        // エラーJSONのパースに失敗した場合は、デフォルトのエラーメッセージを使用
      }
      throw new Error(errorMessage);
    }
  
    return response.json() as Promise<T>;
  }