npm-dev-mcp

Instructions

Implementation Reference

• src/tools/stopDevServer.ts:22-79 (handler)

  The primary handler function for the 'stop_dev_server' MCP tool. It checks for the target process, stops it using ProcessManager, collects log stats, and returns a detailed JSON response.

  export async function stopDevServer(args: { directory?: string }): Promise<string> {
    try {
      const processManager = ProcessManager.getInstance();
  
      // Check if target process exists BEFORE stopping
      const targetProcess = processManager.getProcess(args.directory);
      if (!targetProcess) {
        return JSON.stringify({
          success: false,
          message: '指定されたディレクトリのDev serverは見つかりませんでした（または起動していません）',
          wasRunning: false
        });
      }
  
      logger.info('Stopping dev server', { directory: targetProcess.directory });
  
      const logManager = processManager.getLogManager(targetProcess.directory);
      const finalLogStats = logManager?.getLogStats();
  
      // Stop the dev server
      const stopResult = await processManager.stopDevServer(args.directory);
  
      const result: any = {
        success: stopResult,
        message: stopResult
          ? 'Dev serverを正常に停止しました'
          : 'Dev serverの停止中にエラーが発生しましたが、プロセスは終了した可能性があります',
        wasRunning: true,
        stoppedProcess: {
          pid: targetProcess.pid,
          directory: targetProcess.directory,
          ports: targetProcess.ports
        }
      };
  
      if (finalLogStats) {
        result.finalLogStats = {
          total: finalLogStats.total,
          errors: finalLogStats.errors,
          warnings: finalLogStats.warnings
        };
        if (finalLogStats.errors > 0) {
          result.message += `\n最終ログに${finalLogStats.errors}個のエラーが記録されています`;
        }
      }
  
      return JSON.stringify(result, null, 2);
  
    } catch (error) {
      logger.error('Failed to stop dev server', { error });
      return JSON.stringify({
        success: false,
        message: `Dev serverの停止に失敗しました: ${error}`,
        wasRunning: false,
        error: String(error)
      });
    }
  }

• src/tools/stopDevServer.ts:7-20 (schema)

  Input schema definition for the 'stop_dev_server' tool, defining the optional 'directory' parameter.

  export const stopDevServerSchema: Tool = {
    name: 'stop_dev_server',
    description: 'npm run devプロセス停止',
    inputSchema: {
      type: 'object',
      properties: {
        directory: {
          type: 'string',
          description: '停止対象のディレクトリ（複数起動時に指定。未指定時は唯一のプロセスまたはエラー）'
        }
      },
      additionalProperties: false
    }
  };

• src/index.ts:167-175 (registration)

  Registration and dispatch of the 'stop_dev_server' tool handler in the main CallToolRequestSchema switch statement.

  case 'stop_dev_server':
    return {
      content: [
        {
          type: 'text',
          text: await stopDevServer(args as { directory?: string }),
        },
      ],
    };

• src/components/ProcessManager.ts:128-167 (helper)

  Core helper method in ProcessManager that performs the actual process termination (SIGTERM then SIGKILL if needed) and cleanup, called by the tool handler.

  async stopDevServer(directory?: string): Promise<boolean> {
    this.logger.info(`Stopping dev server${directory ? ` for ${directory}` : ''}`);
  
    const targetDirectory = this.resolveTargetDirectory(directory);
    const processData = this.processes.get(targetDirectory);
  
    if (!processData) {
      this.logger.info(`No dev server running for ${targetDirectory}`);
      return true; // Already stopped or not found
    }
  
    try {
      const pid = processData.info.pid;
  
      // Try graceful shutdown first
      if (processData.child) {
        processData.child.kill('SIGTERM');
      } else {
        await killProcess(pid, 'SIGTERM');
      }
  
      // Wait a moment for graceful shutdown
      await new Promise(resolve => setTimeout(resolve, 3000));
  
      // Check if process is still running
      if (await isProcessRunning(pid)) {
        this.logger.warn(`Process ${pid} did not stop gracefully, forcing termination`);
        await killProcess(pid, 'SIGKILL');
      }
  
      await this.cleanupProcess(targetDirectory);
      this.logger.info(`Dev server stopped successfully for ${targetDirectory}`);
      return true;
  
    } catch (error) {
      this.logger.error(`Failed to stop dev server for ${targetDirectory}`, { error });
      await this.cleanupProcess(targetDirectory); // Clean up anyway
      return false;
    }
  }