Support MCP servers hosting on AgentCore Gateway/Runtime

[zxkane]

Describe the feature (Security related? please follow https://github.com/aws/mcp-proxy-for-aws/security/policy to report them to AWS Security directly.)

I could use this tool to connect the MCP hosting on the AgentCore gateway, but the tools capability could not be discovered by this tool.

Use Case

connect the exiting MCP servers hosting on AgentCore gateway/runtime

Proposed Solution

No response

Other Information

No response

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

[arangatang]

Good day, thank you for opening this issue!
I see from your screenshot that --service is not provided this is used for SigV4 calculation.
The reason the failure happens is that when we autodetect the service it detects the wrong part of the URL -> Signing becomes invalid.

For now I added an override to support AgentCore usecase.
In the meantime before the pr is merged, could you verify that passing

--service bedrock-agentcore solves your issue?

[zxkane]

Looks like it does not work.

[arangatang]

Curious this works on my end, could you share more logs with --log-level DEBUG (do ensure to not share anything sensitive in the logs)?

Also did you ensure you have fresh credentials on your machine with a role that has sufficient IAM permissions to invoke the gateway in question?

When using Kiro, this works from my machine against an IAM protected AgentCore Gateway in my account:

  "myMcpInAgentCoreGateway": {
        "command": "uvx",
        "args": [
          "mcp-proxy-for-aws@latest",
          "https://gateway-quick-start-my-mcp.gateway.bedrock-agentcore.eu-central-1.amazonaws.com/mcp",
          "--region",
          "eu-central-1",
          "--service",
          "bedrock-agentcore",
          "--log-level",
          "DEBUG"
        ]
      }

[zxkane]

It works after specifying the right AWS profile env.

The connected status made it confused though the MCP server auth failed.

[arangatang]

Alright, thank you for clarifying!