build_line
Create straight lines of blocks between two points in Minecraft Bedrock Edition. Customize start and end coordinates to build paths, fences, bridges, or supports with specific materials like stone or wood.
Instructions
Build a straight line of blocks between two points. Perfect for paths, roads, fences, bridges, pillars, or structural frameworks. Example: from (0,64,0) to (10,80,10) creates a diagonal line useful for building supports or artistic structures
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| action | No | Build action to perform | build |
| material | No | Block type to build the line with (e.g. stone, cobblestone, wood, concrete) | minecraft:stone |
| x1 | Yes | Starting X coordinate (east-west position where line begins) | |
| x2 | Yes | Ending X coordinate (east-west position where line ends) | |
| y1 | Yes | Starting Y coordinate (height where line begins, typically 64 for ground level) | |
| y2 | Yes | Ending Y coordinate (height where line ends, can be different for slopes/ramps) | |
| z1 | Yes | Starting Z coordinate (north-south position where line begins) | |
| z2 | Yes | Ending Z coordinate (north-south position where line ends) |
Implementation Reference
- BuildLineTool class: defines the 'build_line' tool with name, description, inputSchema, and the full execute handler method that computes line positions using Bresenham algorithm via calculateLinePositions, validates limits, and builds using executeBuildWithOptimization.
export class BuildLineTool extends BaseTool { readonly name = 'build_line'; readonly description = 'Build a straight line of blocks between two points. Perfect for paths, roads, fences, bridges, pillars, or structural frameworks. Example: from (0,64,0) to (10,80,10) creates a diagonal line useful for building supports or artistic structures'; readonly inputSchema: InputSchema = { type: 'object', properties: { action: { type: 'string', description: 'Build action to perform', enum: ['build'], default: 'build' }, x1: { type: 'number', description: 'Starting X coordinate (east-west position where line begins)' }, y1: { type: 'number', description: 'Starting Y coordinate (height where line begins, typically 64 for ground level)' }, z1: { type: 'number', description: 'Starting Z coordinate (north-south position where line begins)' }, x2: { type: 'number', description: 'Ending X coordinate (east-west position where line ends)' }, y2: { type: 'number', description: 'Ending Y coordinate (height where line ends, can be different for slopes/ramps)' }, z2: { type: 'number', description: 'Ending Z coordinate (north-south position where line ends)' }, material: { type: 'string', description: 'Block type to build the line with (e.g. stone, cobblestone, wood, concrete)', default: 'minecraft:stone' } }, required: ['x1', 'y1', 'z1', 'x2', 'y2', 'z2'] }; /** * 直線構造物を建築します * * @param args - 建築パラメータ * @param args.x1 - 開始点のX座標（東西方向の位置） * @param args.y1 - 開始点のY座標（高さ、通常64が地上レベル） * @param args.z1 - 開始点のZ座標（南北方向の位置） * @param args.x2 - 終了点のX座標（東西方向の位置） * @param args.y2 - 終了点のY座標（高さ、斜面の場合は異なる高さ可） * @param args.z2 - 終了点のZ座標（南北方向の位置） * @param args.material - 使用するブロック素材（デフォルト: "minecraft:stone"） * @returns 建築実行結果 * * @throws Y座標が範囲外の場合（-64から320の範囲外） * @throws 線の長さが制限を超える場合（100ブロック超過） * @throws ブロック数が制限を超える場合（100ブロック超過） * * @example * ```typescript * // 縦方向の橋を建築 * const result = await tool.execute({ * x1: 50, y1: 65, z1: 0, * x2: 50, y2: 75, z2: 20, * material: "cobblestone" * }); * * if (result.success) { * console.log(`直線建築完了: ${result.data.blocksPlaced}ブロック配置`); * } * ``` */ async execute(args: { action?: string; x1: number; y1: number; z1: number; x2: number; y2: number; z2: number; material?: string; }): Promise<ToolCallResult> { try { const { action = 'build', x1, y1, z1, x2, y2, z2, material = 'minecraft:stone' } = 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: ${action}. Only 'build' is supported.`); } // 座標の整数化 const start = { x: Math.floor(x1), y: Math.floor(y1), z: Math.floor(z1) }; const end = { x: Math.floor(x2), y: Math.floor(y2), z: Math.floor(z2) }; // Y座標の検証 if (start.y < -64 || start.y > 320 || end.y < -64 || end.y > 320) { return { success: false, message: 'Y coordinates must be between -64 and 320' }; } // ブロックIDの正規化 let blockId = material; if (!blockId.includes(':')) { blockId = `minecraft:${blockId}`; } // 直線の長さを計算 const distance = Math.sqrt( Math.pow(end.x - start.x, 2) + Math.pow(end.y - start.y, 2) + Math.pow(end.z - start.z, 2) ); if (distance > 100) { return { success: false, message: 'Line too long (maximum 100 blocks)' }; } // 直線の座標を計算 const positions = calculateLinePositions(start, end); if (positions.length > BUILD_LIMITS.LINE) { return { success: false, message: `Too many blocks to place (maximum ${BUILD_LIMITS.LINE.toLocaleString()})` }; } // Socket-BE APIを使用してブロック配置 if (!this.world) { return { success: false, message: 'World not available. Ensure Minecraft is connected.' }; } try { // 最適化されたビルド実行 const result = await executeBuildWithOptimization( this.world, positions, blockId, { type: 'line', from: start, to: end, material: blockId, apiUsed: 'Socket-BE' } ); if (!result.success) { return { success: false, message: result.message }; } return { success: true, message: result.message, data: result.data }; } catch (error) { return { success: false, message: `Building error: ${error instanceof Error ? error.message : String(error)}` }; } } catch (error) { return { success: false, message: `Error building line: ${error instanceof Error ? error.message : String(error)}` }; } } } - Input schema defining parameters for build_line: coordinates (x1,y1,z1 to x2,y2,z2), material, and action.
readonly inputSchema: InputSchema = { type: 'object', properties: { action: { type: 'string', description: 'Build action to perform', enum: ['build'], default: 'build' }, x1: { type: 'number', description: 'Starting X coordinate (east-west position where line begins)' }, y1: { type: 'number', description: 'Starting Y coordinate (height where line begins, typically 64 for ground level)' }, z1: { type: 'number', description: 'Starting Z coordinate (north-south position where line begins)' }, x2: { type: 'number', description: 'Ending X coordinate (east-west position where line ends)' }, y2: { type: 'number', description: 'Ending Y coordinate (height where line ends, can be different for slopes/ramps)' }, z2: { type: 'number', description: 'Ending Z coordinate (north-south position where line ends)' }, material: { type: 'string', description: 'Block type to build the line with (e.g. stone, cobblestone, wood, concrete)', default: 'minecraft:stone' } }, required: ['x1', 'y1', 'z1', 'x2', 'y2', 'z2'] }; - src/server.ts:494-573 (registration)Registration loop in registerModularTools(): iterates over tools array (including BuildLineTool), converts schema to Zod, and calls mcpServer.registerTool for each tool.name ('build_line'), wrapping tool.execute.
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}`, }, ], }; } } ); }); - src/server.ts:359-372 (registration)Instantiation of BuildLineTool added to the tools array in initializeTools(), which is then registered in the MCP server.
// 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） ];