AWS MCP Server

Instructions

Implementation Reference

• src/index.ts:791-810 (handler)

  The handler logic for the 'get_aws_caller_identity' tool. It uses the STSClient to send a GetCallerIdentityCommand and returns the AWS account, UserId, and ARN as JSON.

  if (name === "get_aws_caller_identity") {
      const command = new GetCallerIdentityCommand({});
      const response = await stsClient.send(command);
      return {
          content: [
              {
                  type: "text",
                  text: JSON.stringify(
                      {
                          UserId: response.UserId,
                          Account: response.Account,
                          Arn: response.Arn,
                      },
                      null,
                      2
                  ),
              },
          ],
      };
  }

• src/index.ts:97-104 (registration)

  Tool registration in the ListToolsRequestSchema handler, defining the tool name, description, and empty input schema (no parameters required).

  {
      name: "get_aws_caller_identity",
      description: "Returns the AWS IAM caller identity (user/role) to verify credentials.",
      inputSchema: {
          type: "object",
          properties: {},
      },
  },

• src/index.ts:100-103 (schema)

  Input schema for the tool: an empty object, indicating no input parameters are needed.

  inputSchema: {
      type: "object",
      properties: {},
  },

• src/index.ts:54-54 (helper)

  Instantiation of the STSClient used by the get_aws_caller_identity handler.

  const stsClient = new STSClient({});

• src/index.ts:20-20 (helper)

  Import of STSClient and GetCallerIdentityCommand required for the tool implementation.

  import { STSClient, GetCallerIdentityCommand } from "@aws-sdk/client-sts";