MCP SmallEdit

Instructions

Implementation Reference

• src/index.ts:815-857 (handler)

  The handler function for 'restore_backup' tool. It restores the specified file from its .bak backup (or alternatives), creates a .before-restore safety backup of the current file, writes the backup content back to the original file, optionally deletes the backup, and returns a success message.

  case 'restore_backup': {
    const { file, keepBackup = true } = args;
    
    const backupFile = `${file}.bak`;
    
    // Check if backup exists
    if (!existsSync(backupFile)) {
      // Look for other common backup patterns
      const alternatives = [
        `${file}~`,
        `${file}.backup`,
        `${file}.orig`
      ].filter(existsSync);
      
      if (alternatives.length > 0) {
        throw new Error(`No .bak file found, but found: ${alternatives.join(', ')}`);
      }
      throw new Error(`No backup file found for ${file}`);
    }
    
    // Read backup content
    const backupContent = await readFile(backupFile, 'utf-8');
    
    // Check if current file exists and create a safety backup
    if (existsSync(file)) {
      await writeFile(`${file}.before-restore`, await readFile(file, 'utf-8'));
    }
    
    // Restore the backup
    await writeFile(file, backupContent);
    
    // Remove backup if requested
    if (!keepBackup) {
      await execAsync(`rm -f '${backupFile}'`);
    }
    
    return {
      content: [{
        type: 'text',
        text: `Successfully restored ${file} from backup${!keepBackup ? ' (backup removed)' : ''}\nSafety backup created: ${file}.before-restore`
      }]
    };
  }

• src/index.ts:227-245 (registration)

  Registration of the 'restore_backup' tool in the ListToolsRequestSchema handler, including name, description, and input schema.

  {
    name: 'restore_backup',
    description: 'Restore a file from its most recent backup (.bak)',
    inputSchema: {
      type: 'object',
      properties: {
        file: {
          type: 'string',
          description: 'File to restore from backup'
        },
        keepBackup: {
          type: 'boolean',
          default: true,
          description: 'Keep the backup file after restoring'
        }
      },
      required: ['file']
    }
  },

• src/index.ts:231-243 (schema)

  Input schema definition for the restore_backup tool, specifying parameters 'file' (required) and 'keepBackup' (optional boolean).

  type: 'object',
  properties: {
    file: {
      type: 'string',
      description: 'File to restore from backup'
    },
    keepBackup: {
      type: 'boolean',
      default: true,
      description: 'Keep the backup file after restoring'
    }
  },
  required: ['file']

• src/index.ts:512-532 (helper)

  Help text and usage examples for the restore_backup tool in the helpContent object.

    restore_backup: `restore_backup - Restore from backup
  =================================
  Restore a file from its .bak backup file.
  
  Examples:
    // Basic restore
    restore_backup({ file: "config.json" })
    // Looks for config.json.bak and restores it
    
    // Restore and remove backup
    restore_backup({ file: "data.txt", keepBackup: false })
    
    // After a bad edit
    sed_edit({ file: "app.js", pattern: "s/function/fungtion/g" }) // Oops!
    restore_backup({ file: "app.js" }) // Fixed!
  
  Safety features:
  - Creates .before-restore backup of current file
  - Checks for alternative backup formats (.backup, .orig, ~)
  - Clear error if no backup found
  `,