Minecraft Bedrock MCP Server

Instructions

Implementation Reference

• src/tools/core/agent.ts:84-230 (handler)

  Core handler function implementing all 'agent' tool actions (move, turn, teleport, attack, mine/place blocks, inventory ops, sequences) via switch on 'action' param.
  async execute(args: { action: string; direction?: string; distance?: number; x?: number; y?: number; z?: number; slot?: number; item_id?: string; amount?: number; data?: number; steps?: SequenceStep[]; }): Promise<ToolCallResult> { if (!this.agent) { return { success: false, message: 'Agent not available. Ensure Minecraft is connected and agent is spawned.' }; } try { const { action } = args; let result: any; let message: string; switch (action) { case 'move': if (!args.direction) return { success: false, message: 'Direction required for move' }; const distance = args.distance || 1; for (let i = 0; i < distance; i++) { await this.agent.move(args.direction as AgentDirection); } message = distance === 1 ? `Agent moved ${args.direction}` : `Agent moved ${distance} blocks ${args.direction}`; break; case 'turn': if (!args.direction || !['left', 'right'].includes(args.direction)) { return { success: false, message: 'Direction must be "left" or "right" for turn' }; } await this.agent.turn(args.direction as AgentDirection.Left | AgentDirection.Right); message = `Agent turned ${args.direction}`; break; case 'teleport': if (args.x !== undefined && args.y !== undefined && args.z !== undefined) { await this.agent.teleport({ x: args.x, y: args.y, z: args.z }); message = `Agent teleported to (${args.x}, ${args.y}, ${args.z})`; result = { x: args.x, y: args.y, z: args.z }; } else { await this.agent.teleport(); message = 'Agent teleported to player location'; } break; case 'attack': if (!args.direction) return { success: false, message: 'Direction required for attack' }; await this.agent.attack(args.direction as AgentDirection); message = `Agent attacked ${args.direction}`; break; case 'mine_block': if (!args.direction) return { success: false, message: 'Direction required for mine_block' }; await this.agent.destroyBlock(args.direction as AgentDirection); message = `Agent mined block ${args.direction}`; break; case 'place_block': if (!args.direction || !args.slot) return { success: false, message: 'Direction and slot required for place_block' }; await this.agent.placeBlock(args.direction as AgentDirection, args.slot); message = `Agent placed block from slot ${args.slot} ${args.direction}`; break; case 'inspect_block': if (!args.direction) return { success: false, message: 'Direction required for inspect_block' }; result = await this.agent.inspect(args.direction as AgentDirection); message = `Agent inspected block ${args.direction}`; break; case 'detect_block': if (!args.direction) return { success: false, message: 'Direction required for detect_block' }; result = await this.agent.detect(args.direction as AgentDirection); message = `Agent detected block ${args.direction}`; break; case 'get_position': result = await this.agent.getLocation(); message = 'Agent position retrieved'; break; case 'collect_item': if (!args.item_id) return { success: false, message: 'item_id required for collect_item' }; await this.agent.collect(args.item_id); message = `Agent collected ${args.item_id}`; break; case 'drop_item': if (!args.direction || !args.slot) return { success: false, message: 'Direction and slot required for drop_item' }; const dropAmount = args.amount || 1; await this.agent.dropItem(args.direction as AgentDirection, args.slot, dropAmount); message = `Agent dropped ${dropAmount} items from slot ${args.slot} ${args.direction}`; break; case 'drop_all': if (!args.direction) return { success: false, message: 'Direction required for drop_all' }; await this.agent.dropAllItems(args.direction as AgentDirection); message = `Agent dropped all items ${args.direction}`; break; case 'get_inventory': if (!args.slot) return { success: false, message: 'Slot required for get_inventory' }; const itemDetail = await this.agent.getItemDetail(args.slot); const itemCount = await this.agent.getItemCount(args.slot); const itemSpace = await this.agent.getItemSpace(args.slot); result = { detail: itemDetail, count: itemCount, space: itemSpace }; message = `Inventory info for slot ${args.slot} retrieved`; break; case 'set_item_in_slot': if (!args.slot || !args.item_id) return { success: false, message: 'Slot and item_id required for set_item_in_slot' }; const setAmount = args.amount || 1; const setData = args.data || 0; await this.agent.setItem(args.slot, args.item_id, setAmount, setData); message = `Set ${setAmount} ${args.item_id} in slot ${args.slot}`; break; case 'sequence': if (!args.steps) { return this.createErrorResponse('steps array is required for sequence action'); } return await this.executeSequence(args.steps as SequenceStep[]); default: return { success: false, message: `Unknown action: ${action}` }; } return { success: true, message: message, data: { action, result, timestamp: Date.now() } }; } catch (error) { return { success: false, message: `Agent operation error: ${error instanceof Error ? error.message : String(error)}` }; } }
• src/tools/core/agent.ts:13-68 (schema)

  Input schema defining parameters for agent tool: action (enum), direction, distance, coords, slots, items, etc.
  readonly inputSchema: InputSchema = { type: 'object', properties: { action: { type: 'string', description: 'Agent action to perform', enum: [ 'move', 'turn', 'teleport', 'attack', 'mine_block', 'place_block', 'inspect_block', 'detect_block', 'get_position', 'collect_item', 'drop_item', 'drop_all', 'get_inventory', 'set_item_in_slot', 'sequence' ] }, direction: { type: 'string', description: 'Direction for movement/rotation/block operations', enum: ['forward', 'back', 'left', 'right', 'up', 'down'] }, distance: { type: 'number', description: 'Number of blocks to move (1-10)', minimum: 1, maximum: 10, default: 1 }, x: { type: 'number', description: 'X coordinate for teleportation' }, y: { type: 'number', description: 'Y coordinate for teleportation' }, z: { type: 'number', description: 'Z coordinate for teleportation' }, slot: { type: 'number', description: 'Inventory slot (1-16)', minimum: 1, maximum: 16 }, item_id: { type: 'string', description: 'Item ID (e.g., minecraft:stone, minecraft:dirt)' }, amount: { type: 'number', description: 'Item amount (1-64)', minimum: 1, maximum: 64, default: 1 }, data: { type: 'number', description: 'Item data/aux value', default: 0 }, steps: { type: 'array', description: 'Array of agent actions for sequence. Each step should have "type" field and relevant parameters.' } }, required: ['action'] };
• src/server.ts:348-372 (registration)

  Instantiation of AgentTool() and inclusion in the tools array.
  this.tools = [ // Socket-BE Core API ツール（推奨 - シンプルでAI使いやすい） new AgentTool(), new WorldTool(), new PlayerTool(), new BlocksTool(), new SystemTool(), new CameraTool(), new SequenceTool(), new MinecraftWikiTool(), // 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:494-573 (registration)

  Registration loop using mcpServer.registerTool for each tool (including 'agent') with name, desc, converted schema, and execute wrapper.
  this.tools.forEach((tool) => { // inputSchemaをZod形式に変換（SchemaToZodConverterを使用） const zodSchema = schemaConverter.convert(tool.inputSchema); // ツールを登録 this.mcpServer.registerTool( tool.name, { title: tool.name, description: tool.description, inputSchema: zodSchema, }, async (args: any) => { try { const result = await tool.execute(args); let responseText: string; if (result.success) { // 建築ツールの場合は最適化 if (tool.name.startsWith('build_')) { const optimized = optimizeBuildResult(result); responseText = `✅ ${optimized.message}`; if (optimized.summary) { responseText += `\n\n📊 Summary:\n${JSON.stringify(optimized.summary, null, 2)}`; } } else { // 通常ツールの場合 responseText = result.message || `Tool ${tool.name} executed successfully`; if (result.data) { // データサイズチェック const dataStr = JSON.stringify(result.data, null, 2); const sizeWarning = checkResponseSize(dataStr); if (sizeWarning) { // 大きすぎる場合はデータタイプのみ表示 responseText += `\n\n${sizeWarning}`; responseText += `\nData type: ${Array.isArray(result.data) ? `Array[${result.data.length}]` : typeof result.data}`; } else { responseText += `\n\nData: ${dataStr}`; } } } } else { // エラーメッセージにヒントを追加 const errorMsg = result.message || "Tool execution failed"; const enrichedError = enrichErrorWithHints(errorMsg); responseText = `❌ ${enrichedError}`; if (result.data) { responseText += `\n\nDetails:\n${JSON.stringify(result.data, null, 2)}`; } } return { content: [ { type: "text", text: responseText, }, ], }; } catch (error) { const errorMsg = error instanceof Error ? error.message : String(error); const errorStack = error instanceof Error ? error.stack : undefined; const exceptionMessage = `Tool execution failed with exception: ${errorMsg}${errorStack ? `\n\nStack trace:\n${errorStack}` : ""}`; return { content: [ { type: "text", text: `❌ ${exceptionMessage}`, }, ], }; } } ); });