mcp-proxy-for-aws-multi 0.1.0

Multi-endpoint MCP Proxy for AWS with automatic tool merging

MCP Proxy for AWS (Multi-Endpoint)

Overview

mcp-proxy-for-aws-multi is a multi-endpoint MCP proxy that connects AI applications to multiple MCP servers simultaneously. It automatically merges tools and resources from all endpoints into a single unified interface, with intelligent routing of calls to the correct backend.

Key features:

• Multi-endpoint support — connect to one or more MCP endpoints and get a merged tool/resource list
• Automatic SigV4 signing — AWS MCP endpoints (.api.aws) are signed automatically using your local credentials
• Plain HTTP passthrough — non-AWS endpoints (e.g. localhost) are connected without signing
• Automatic tool routing — tool calls are routed to the correct backend transparently

When Do You Need This Package?

• You want to connect to multiple MCP servers (e.g., AWS MCP + a local UI server) through a single proxy
• You need SigV4 authentication for AWS MCP endpoints
• You want tools from multiple servers merged automatically without manual configuration

Prerequisites

• Python 3.10+
• uv package manager
• AWS credentials configured (for AWS MCP endpoints)

Installation

# Install from PyPI
pip install mcp-proxy-for-aws-multi

# Or run directly with uvx
uvx mcp-proxy-for-aws-multi@latest <endpoint1> [endpoint2]

Usage

Single endpoint (AWS MCP with SigV4)

mcp-proxy-for-aws-multi https://aws-mcp.us-east-1.api.aws/mcp

Multiple endpoints (AWS MCP + local server)

mcp-proxy-for-aws-multi https://aws-mcp.us-east-1.api.aws/mcp http://localhost:8000/mcp

Tools and resources from both endpoints are merged. Calls are routed to the correct backend automatically.

MCP Client Configuration

Add to your MCP client config (e.g., Claude Desktop, Kiro CLI):

{
  "mcpServers": {
    "aws-mcp": {
      "command": "uvx",
      "args": [
        "mcp-proxy-for-aws-multi@latest",
        "https://aws-mcp.us-east-1.api.aws/mcp",
        "http://localhost:8000/mcp"
      ]
    }
  }
}

Configuration Parameters

Parameter	Description	Default	Required
endpoints	One or more MCP endpoint URLs	N/A	Yes (at least one)
--service	AWS service name for SigV4 signing	Inferred from endpoint	No
--profile	AWS profile for credentials	AWS_PROFILE env var	No
--region	AWS region for signing	Inferred from endpoint	No
--metadata	Metadata key=value pairs to inject	AWS_REGION auto-injected	No
--read-only	Disable tools requiring write permissions	False	No
--retries	Number of retries (0-10)	0	No
--log-level	Logging level	ERROR	No
--timeout	Overall timeout (seconds)	180	No
--connect-timeout	Connection timeout (seconds)	60	No
--read-timeout	Read timeout (seconds)	120	No
--write-timeout	Write timeout (seconds)	180	No
--tool-timeout	Max seconds per tool call	300	No
--disable-telemetry	Disable telemetry	False	No

How It Works

1. Endpoint detection — URLs matching .api.aws/ are signed with SigV4. Other URLs use plain HTTP.
2. Provider registration — each endpoint becomes a FastMCP ProxyProvider
3. Tool merging — tools/list queries all providers in parallel and merges results
4. Call routing — tools/call is routed to the provider that owns the tool
5. Same for resources — resources/list and resources/read follow the same pattern

Programmatic Access

The library also provides direct programmatic access for AI agent frameworks:

from mcp_proxy_for_aws.client import aws_iam_streamablehttp_client

mcp_client = aws_iam_streamablehttp_client(
    endpoint="https://aws-mcp.us-east-1.api.aws/mcp",
    aws_region="us-east-1",
    aws_service="execute-api",
)

See the ./examples/mcp-client directory for complete examples with LangChain, LlamaIndex, Strands Agents, and Microsoft Agent Framework.

Troubleshooting

Authentication errors

Ensure valid AWS credentials are configured. For long-running sessions, use AWS SSO:

aws sso login

The proxy auto-detects credential expiry and picks up refreshed credentials on the next request.

Tool call timeouts

Use --tool-timeout to set a maximum duration per tool call. Defaults to 300 seconds.

License

Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. Licensed under the Apache License, Version 2.0.