Minecraft Bedrock MCP Server

Instructions

Implementation Reference

• src/tools/advanced/building/build-cylinder.ts:132-269 (handler)

  The primary handler function that implements the build_cylinder tool logic: validates inputs, calculates cylinder positions, checks limits, and executes the build using optimized build executor.

  async execute(args: {
      action?: string;
      centerX: number;
      centerY: number;
      centerZ: number;
      radius: number;
      height: number;
      material?: string;
      hollow?: boolean;
      axis?: string;
  }): Promise<ToolCallResult> {
      try {
          // Socket-BE API接続確認
          if (!this.world) {
              return { success: false, message: "World not available. Ensure Minecraft is connected." };
          }
  
          // 引数の基本検証
          if (!args || typeof args !== 'object') {
              return this.createErrorResponse('Invalid arguments provided');
          }
  
          if (!this.validateArgs(args)) {
              return this.createErrorResponse('Missing required arguments: centerX, centerY, centerZ, radius, height');
          }
  
          const { 
              action = 'build',
              centerX, 
              centerY, 
              centerZ, 
              radius, 
              height, 
              material = 'minecraft:stone', 
              hollow = false,
              axis = 'y'
          } = args;
          
          // actionパラメータをサポート（現在は build のみ）
          if (action !== 'build') {
              return this.createErrorResponse(`Unknown action: ${action}. Only 'build' is supported.`);
          }
          
          // 座標の整数化
          const center = {
              x: this.normalizeCoordinate(centerX),
              y: this.normalizeCoordinate(centerY),
              z: this.normalizeCoordinate(centerZ)
          };
          
          const radiusInt = Math.round(radius);
          const heightInt = Math.round(height);
          
          // パラメータ検証
          if (radiusInt < 1 || radiusInt > 30) {
              return this.createErrorResponse('Radius must be between 1 and 30');
          }
          
          if (heightInt < 1 || heightInt > 50) {
              return this.createErrorResponse('Height must be between 1 and 50');
          }
          
          if (!['x', 'y', 'z'].includes(axis)) {
              return this.createErrorResponse('Axis must be x, y, or z');
          }
          
          // 座標検証（軸に応じて範囲をチェック）
          let minX = center.x, maxX = center.x;
          let minY = center.y, maxY = center.y;
          let minZ = center.z, maxZ = center.z;
          
          if (axis === 'y') {
              minX = center.x - radiusInt; maxX = center.x + radiusInt;
              minY = center.y; maxY = center.y + heightInt - 1;
              minZ = center.z - radiusInt; maxZ = center.z + radiusInt;
          } else if (axis === 'x') {
              minX = center.x; maxX = center.x + heightInt - 1;
              minY = center.y - radiusInt; maxY = center.y + radiusInt;
              minZ = center.z - radiusInt; maxZ = center.z + radiusInt;
          } else if (axis === 'z') {
              minX = center.x - radiusInt; maxX = center.x + radiusInt;
              minY = center.y - radiusInt; maxY = center.y + radiusInt;
              minZ = center.z; maxZ = center.z + heightInt - 1;
          }
          
          if (!this.validateCoordinates(minX, minY, minZ) || 
              !this.validateCoordinates(maxX, maxY, maxZ)) {
              return this.createErrorResponse('Cylinder extends beyond valid coordinates');
          }
          
          // ブロックIDの正規化
          const blockId = this.normalizeBlockId(material);
          
          // 円柱の座標を計算
          const positions = calculateCylinderPositions(center, radiusInt, heightInt, axis as 'x' | 'y' | 'z', hollow);
          
          // ブロック数制限チェック（最適化効果を考慮）
          if (positions.length > BUILD_LIMITS.CYLINDER) {
              return this.createErrorResponse(`Too many blocks to place (maximum ${BUILD_LIMITS.CYLINDER.toLocaleString()})`);
          }
          
          try {
              // 最適化されたビルド実行
              const result = await executeBuildWithOptimization(
                  this.world,
                  positions,
                  blockId,
                  {
                      type: 'cylinder',
                      center: center,
                      radius: radiusInt,
                      height: heightInt,
                      axis: axis,
                      hollow: hollow,
                      material: blockId,
                      apiUsed: 'Socket-BE'
                  }
              );
              
              if (!result.success) {
                  return this.createErrorResponse(result.message);
              }
              
              return {
                  success: true,
                  message: result.message,
                  data: result.data
              };
          } catch (buildError) {
              return this.createErrorResponse(`Building error: ${buildError instanceof Error ? buildError.message : String(buildError)}`);
          }
  
      } catch (error) {
          return this.createErrorResponse(
              `Error building cylinder: ${error instanceof Error ? error.message : String(error)}`
          );
      }
  }

• src/tools/advanced/building/build-cylinder.ts:44-95 (schema)

  Input schema defining parameters for the build_cylinder tool including required coordinates, radius, height, and optional material, hollow, axis.

  readonly inputSchema: InputSchema = {
      type: 'object',
      properties: {
          action: {
              type: 'string',
              description: 'Build action to perform',
              enum: ['build'],
              default: 'build'
          },
          centerX: {
              type: 'number',
              description: 'Center X coordinate (east-west position where the cylinder will be centered)'
          },
          centerY: {
              type: 'number', 
              description: 'Bottom Y coordinate (ground level height where cylinder starts, typically 64)'
          },
          centerZ: {
              type: 'number',
              description: 'Center Z coordinate (north-south position where the cylinder will be centered)'
          },
          radius: {
              type: 'number',
              description: 'Radius in blocks (how wide the cylinder is). Thin: 2-4, Medium: 5-10, Wide: 15-30',
              minimum: 1,
              maximum: 30
          },
          height: {
              type: 'number',
              description: 'Height in blocks (how tall the cylinder is). Short: 5-10, Medium: 15-25, Tall: 30-50',
              minimum: 1,
              maximum: 50
          },
          material: {
              type: 'string',
              description: 'Block type to build with (e.g. stone, brick, concrete, wood, etc.)',
              default: 'minecraft:stone'
          },
          hollow: {
              type: 'boolean',
              description: 'Make it hollow (true) for cylinder shell/walls only, or solid (false) for full cylinder',
              default: false
          },
          axis: {
              type: 'string',
              description: 'Direction the cylinder extends: y=vertical (normal tower), x=horizontal east-west, z=horizontal north-south',
              enum: ['y', 'x', 'z'],
              default: 'y'
          }
      },
      required: ['centerX', 'centerY', 'centerZ', 'radius', 'height']
  };

• src/server.ts:359-372 (registration)

  Instantiation of BuildCylinderTool in the tools array within the server constructor, which leads to its registration via registerModularTools() method.

    // Advanced Building ツール（高レベル建築機能）
    new BuildCubeTool(), // ✅ 完全動作
    new BuildLineTool(), // ✅ 完全動作
    new BuildSphereTool(), // ✅ 完全動作
    new BuildCylinderTool(), // ✅ 修正済み
    new BuildParaboloidTool(), // ✅ 基本動作
    new BuildHyperboloidTool(), // ✅ 基本動作
    new BuildRotateTool(), // ✅ 基本動作
    new BuildTransformTool(), // ✅ 基本動作
    new BuildTorusTool(), // ✅ 修正完了
    new BuildHelixTool(), // ✅ 修正完了
    new BuildEllipsoidTool(), // ✅ 修正完了
    new BuildBezierTool(), // ✅ 新規追加（可変制御点ベジェ曲線）
  ];

• src/server.ts:17-17 (registration)

  Import statement for BuildCylinderTool used in server registration.

  import { BuildCylinderTool } from "./tools/advanced/building/build-cylinder";