Claude Desktop Commander MCP

Instructions

Implementation Reference

• src/command-manager.ts:33-41 (handler)

  Core implementation of the block_command tool. Adds the command to the blockedCommands Set (after normalizing to lowercase), saves to config file, returns true if newly blocked.

  async blockCommand(command: string): Promise<boolean> {
    command = command.toLowerCase().trim();
    if (this.blockedCommands.has(command)) {
      return false;
    }
    this.blockedCommands.add(command);
    await this.saveBlockedCommands();
    return true;
  }

• src/server.ts:236-242 (handler)

  MCP server handler for block_command tool call. Parses input args and invokes commandManager.blockCommand.

  case "block_command": {
    const parsed = BlockCommandArgsSchema.parse(args);
    const blockResult = await commandManager.blockCommand(parsed.command);
    return {
      content: [{ type: "text", text: blockResult }],
    };
  }

• src/server.ts:102-107 (registration)

  Registers the block_command tool in the MCP server's tool list with description and input schema.

  {
    name: "block_command",
    description:
      "Add a command to the blacklist. Once blocked, the command cannot be executed until unblocked.",
    inputSchema: zodToJsonSchema(BlockCommandArgsSchema),
  },

• src/tools/schemas.ts:23-25 (schema)

  Zod schema for validating block_command input: requires a 'command' string.

  export const BlockCommandArgsSchema = z.object({
    command: z.string(),
  });