Redis MCP Server

Instructions

Implementation Reference

• src/tools/hget_tool.ts:5-38 (handler)

  The HGetTool class that implements the core logic for the 'hget' tool, including validation and execution using Redis client.hGet(key, field).

  export class HGetTool extends RedisTool {
    name = 'hget';
    description = 'Get the value of a hash field';
    inputSchema = {
      type: 'object',
      properties: {
        key: { type: 'string', description: 'Hash key' },
        field: { type: 'string', description: 'Field to get' }
      },
      required: ['key', 'field']
    };
  
    validateArgs(args: unknown): args is HGetArgs {
      return typeof args === 'object' && args !== null &&
        'key' in args && typeof (args as any).key === 'string' &&
        'field' in args && typeof (args as any).field === 'string';
    }
  
    async execute(args: unknown, client: RedisClientType): Promise<ToolResponse> {
      if (!this.validateArgs(args)) {
        return this.createErrorResponse('Invalid arguments for hget');
      }
  
      try {
        const value = await client.hGet(args.key, args.field);
        if (value === null || value === undefined) {
          return this.createSuccessResponse('Field not found');
        }
        return this.createSuccessResponse(value);
      } catch (error) {
        return this.createErrorResponse(`Failed to get hash field: ${error}`);
      }
    }
  }

• src/interfaces/types.ts:11-14 (schema)

  Interface defining the input arguments for the hget tool (key and field). Used for type checking in the tool.

  export interface HGetArgs {
    key: string;
    field: string;
  }

• src/tools/tool_registry.ts:3-27 (registration)

  Import and instantiation of HGetTool in ToolRegistry's default tools list, registering it by name 'hget'.

  import { HGetTool } from './hget_tool.js';
  import { HGetAllTool } from './hgetall_tool.js';
  import { ScanTool } from './scan_tool.js';
  import { SetTool } from './set_tool.js';
  import { GetTool } from './get_tool.js';
  import { DelTool } from './del_tool.js';
  import { ZAddTool } from './zadd_tool.js';
  import { ZRangeTool } from './zrange_tool.js';
  import { ZRangeByScoreTool } from './zrangebyscore_tool.js';
  import { ZRemTool } from './zrem_tool.js';
  import { SAddTool } from './sadd_tool.js';
  import { SMembersTool } from './smembers_tool.js';
  
  export class ToolRegistry {
    private tools: Map<string, BaseTool>;
  
    constructor() {
      this.tools = new Map();
      this.registerDefaultTools();
    }
  
    private registerDefaultTools() {
      const defaultTools = [
        new HMSetTool(),
        new HGetTool(),

• src/tools/hget_tool.ts:8-15 (schema)

  JSON schema definition for hget tool inputs, defining properties and requirements.

  inputSchema = {
    type: 'object',
    properties: {
      key: { type: 'string', description: 'Hash key' },
      field: { type: 'string', description: 'Field to get' }
    },
    required: ['key', 'field']
  };

• src/tools/tool_registry.ts:24-44 (registration)

  The registerDefaultTools method in ToolRegistry that instantiates and registers all default tools, including HGetTool.

  private registerDefaultTools() {
    const defaultTools = [
      new HMSetTool(),
      new HGetTool(),
      new HGetAllTool(),
      new ScanTool(),
      new SetTool(),
      new GetTool(),
      new DelTool(),
      new ZAddTool(),
      new ZRangeTool(),
      new ZRangeByScoreTool(),
      new ZRemTool(),
      new SAddTool(),
      new SMembersTool(),
    ];
  
    for (const tool of defaultTools) {
      this.registerTool(tool);
    }
  }