Introducing OAuth Support for AWS MCP Server

You can now connect your agents to the AWS MCP Server using the same credentials and sign-in methods that you already use for connecting to the AWS Management Console or AWS Command Line Interface (AWS CLI) through a familiar browser-based experience powered by industry-standard OAuth. This new sign-in path supports AWS Identity and Access Management (IAM) federation, AWS IAM Identity Center, and root or IAM users.

In addition, AWS is introducing several new security and governance tools, including: new global condition keys for OAuth, token introspection and revocation, dynamic client registration, new AWS CloudTrail elements, and a new API for headless OAuth connectivity. All of this is compatible with your existing IAM configuration including permissions, roles, and federated access.

In this post, you’ll learn how to connect your agents to the AWS MCP Server, understand how AWS Sign-In authorizes agent access, and manage access using new security and governance capabilities.

This walkthrough uses Claude Code, but the same steps apply to any agent that supports Model Context Protocol (MCP) such as Kiro, Codex, and Gemini. See Setting up the AWS MCP Server for how to connect the AWS MCP Server to an agent.

To connect an agent to the AWS MCP Server, you’ll need the IAM permissions required for OAuth-based sign-in. The following AWS CLI command adds a managed policy with required permissions to your IAM role (remember to replace <MyRole> with your IAM role):

aws iam attach-role-policy \
  --role-name <MyRole> \
  --policy-arn arn:aws:iam::aws:policy/AWSMCPSignInOAuthAccessPolicy

Run the following command to add the AWS MCP Server endpoint to your agent’s configuration as shown in Figure 1:

claude mcp add --transport http aws-mcp https://aws-mcp.us-east-1.api.aws/mcp

Figure 1: Adding the AWS MCP Server endpoint to Claude Code

The first time your agent needs to access the AWS MCP Server, it opens a browser and redirects you to an AWS Sign-In page, shown in Figure 2. Authenticate as you would on AWS console or AWS CLI, review the authorization request, and approve access. You should receive an Authorization successful message.

Figure 2: Review authorization request

Note that if you already have an active AWS Sign-In session (e.g., because you previously signed in to the console earlier in the day), you can reuse that session without needing to sign in again.

After connecting your agent to the AWS MCP Server, you can begin invoking tools provided by the server. To verify that Claude Code is connected to the AWS MCP Server, start Claude Code and run the following command:

/mcp

The command displays the configured MCP servers and confirms that the AWS MCP Server is connected and ready to use with your AWS credentials.

Figure 3 shows an example of a successful connection to the AWS MCP Server.

Figure 3: Verifying the AWS MCP Server connection in Claude Code

After the connection is established, you can ask Claude Code to invoke tools provided by the AWS MCP Server. For example, enter the following prompt:

Deploy a sample serverless web application into my development AWS account

Claude Code uses the AWS MCP Server to identify the active AWS account, confirm the target account, and describe the deployment it plans to perform before invoking AWS services on your behalf.

Figure 4 shows Claude Code confirming the active AWS account and outlining the resources that will be deployed.

Figure 4: Using Claude Code to deploy a sample serverless application through the AWS MCP Server

AWS Sign-In supports two authorization models for connecting agents to the AWS MCP Server:

• Interactive authorization for developers’ AI agents using browser based authentication
• Non-interactive (headless) authorization for applications and AI agents that already have AWS credentials and don’t have access to a browser

Note that authorizing an agent allows it to access the AWS MCP Server on your behalf. It doesn’t grant the agent additional AWS permissions. Every request is still evaluated using your existing IAM policies, SCPs, RCPs, permission boundaries, and other organizational controls.

In the interactive case, the agent first discovers the AWS Sign-In OAuth server and then registers itself as an OAuth client using Dynamic Client Registration (DCR). It then redirects you to an AWS Sign-In page where you authenticate and authorize access (step 2 in the preceding section). After successful authorization, AWS Sign-In then issues short-lived access tokens and refresh tokens that authorize the agent to access the AWS MCP Server on your behalf. AWS Sign-In automatically manages token issuance and token refresh, enabling authorized agents to continue accessing the AWS MCP Server without requiring you to repeatedly sign in.

The interactive authorization model supports three distinct sign-in methods: native AWS IAM credentials for individual developers, managed access through AWS IAM Identity Center for enterprises, and seamless feder