Redis MCP Server

Instructions

Implementation Reference

• src/tools/scan_tool.ts:30-50 (handler)

  The core handler function that executes the 'scan' tool logic: validates input, scans Redis keys matching the pattern using client.keys(), limits results to 10 keys max, and returns a JSON-formatted list or error response.

  async execute(args: unknown, client: RedisClientType): Promise<ToolResponse> {
    if (!this.validateArgs(args)) {
      return this.createErrorResponse('Invalid arguments for scan');
    }
  
    try {
      const { pattern, count = 100 } = args;
      const keys = await client.keys(pattern);
      
      if (keys.length === 0) {
        return this.createSuccessResponse('No keys found matching pattern');
      }
  
      // Limit keys to at most 10, or less if count is specified and smaller
      const maxKeys = Math.min(count || 10, 10);
      const limitedKeys = keys.slice(0, maxKeys);
      return this.createSuccessResponse(JSON.stringify(limitedKeys, null, 2));
    } catch (error) {
      return this.createErrorResponse(`Failed to scan keys: ${error}`);
    }
  }

• src/tools/scan_tool.ts:8-22 (schema)

  JSON schema defining the input parameters for the 'scan' tool: required 'pattern' string and optional 'count' number.

  inputSchema = {
    type: 'object',
    properties: {
      pattern: {
        type: 'string',
        description: 'Pattern to match (e.g., "user:*" or "schedule:*")'
      },
      count: {
        type: 'number',
        description: 'Number of keys to return per iteration (optional)',
        minimum: 1
      }
    },
    required: ['pattern']
  };

• src/tools/tool_registry.ts:29-29 (registration)

  Registration of the ScanTool instance in the default tools array of ToolRegistry.

  new ScanTool(),

• src/interfaces/types.ts:41-44 (schema)

  TypeScript interface defining the expected arguments for the 'scan' tool.

  export interface ScanArgs {
    pattern: string;
    count?: number;
  }

• src/tools/scan_tool.ts:24-28 (helper)

  Helper function to validate input arguments match ScanArgs structure.

  validateArgs(args: unknown): args is ScanArgs {
    return typeof args === 'object' && args !== null &&
      'pattern' in args && typeof (args as any).pattern === 'string' &&
      (!('count' in args) || typeof (args as any).count === 'number');
  }