AWS Bedrock KB Retrieval

Amazon Bedrock Knowledge Base Retrieval MCP Server

MCP server for accessing Amazon Bedrock Knowledge Bases

Features

Discover knowledge bases and their data sources

• Find and explore all available knowledge bases

• Search for knowledge bases by name or tag

• List data sources associated with each knowledge base

Query knowledge bases with natural language

• Retrieve information using conversational queries

• Get relevant passages from your knowledge bases

• Access citation information for all results

Filter results by data source

• Focus your queries on specific data sources

• Include or exclude specific data sources

• Prioritize results from specific data sources

Rerank results

• Improve relevance of retrieval results

• Use Amazon Bedrock reranking capabilities

• Sort results by relevance to your query

Prerequisites

Installation Requirements

• Install uv from Astral or the GitHub README

• Install Python using uv python install 3.10

AWS Requirements

• AWS CLI Configuration: You must have the AWS CLI configured with credentials and an AWS_PROFILE that has access to Amazon Bedrock and Knowledge Bases

• Amazon Bedrock Knowledge Base: You must have at least one Amazon Bedrock Knowledge Base with the tag key mcp-multirag-kb with a value of true

• IAM Permissions: Your IAM role/user must have appropriate permissions to:

• List and describe knowledge bases

• Access data sources

• Query knowledge bases

Reranking Requirements

If you intend to use reranking functionality, your Bedrock Knowledge Base needs additional permissions:

• Your IAM role must have permissions for both bedrock:Rerank and bedrock:InvokeModel actions

• The Amazon Bedrock Knowledge Bases service role must also have these permissions

• Reranking is only available in specific regions. Please refer to the official documentation for an up to date list of supported regions.

• Enable model access for the available reranking models in the specified region.

Controlling Reranking

Reranking can be globally enabled or disabled using the BEDROCK_KB_RERANKING_ENABLED environment variable:

• Set to false (default): Disables reranking for all queries unless explicitly enabled

• Set to true: Enables reranking for all queries unless explicitly disabled

The environment variable accepts various formats:

• For enabling: 'true', '1', 'yes', or 'on' (case-insensitive)

• For disabling: any other value or not set (default behavior)

This setting provides a global default, while individual API calls can still override it by explicitly setting the reranking parameter.

For detailed instructions on setting up knowledge bases, see:

• Create a knowledge base

• Managing permissions for Amazon Bedrock knowledge bases

• Permissions for reranking in Amazon Bedrock

Installation

Kiro Cursor VS Code

Configure the MCP server in your MCP client configuration (e.g., for Kiro, edit ~/.kiro/settings/mcp.json):

{
 "mcpServers": {
 "awslabs.bedrock-kb-retrieval-mcp-server": {
 "command": "uvx",
 "args": ["awslabs.bedrock-kb-retrieval-mcp-server@latest"],
 "env": {
 "AWS_PROFILE": "your-profile-name",
 "AWS_REGION": "us-east-1",
 "FASTMCP_LOG_LEVEL": "ERROR",
 "KB_INCLUSION_TAG_KEY": "optional-tag-key-to-filter-kbs",
 "BEDROCK_KB_RERANKING_ENABLED": "false"
 },
 "disabled": false,
 "autoApprove": []
 }
 }
}

Windows Installation

For Windows users, the MCP server configuration format is slightly different:

{
 "mcpServers": {
 "awslabs.bedrock-kb-retrieval-mcp-server": {
 "disabled": false,
 "timeout": 60,
 "type": "stdio",
 "command": "uv",
 "args": [
 "tool",
 "run",
 "--from",
 "awslabs.bedrock-kb-retrieval-mcp-server@latest",
 "awslabs.bedrock-kb-retrieval-mcp-server.exe"
 ],
 "env": {
 "FASTMCP_LOG_LEVEL": "ERROR",
 "AWS_PROFILE": "your-aws-profile",
 "AWS_REGION": "us-east-1"
 }
 }
 }
}

or docker after a successful docker build -t awslabs/bedrock-kb-retrieval-mcp-server .:

# fictitious `.env` file with AWS temporary credentials
AWS_ACCESS_KEY_ID=ASIAIOSFODNN7EXAMPLE
AWS_SECRET_ACCESS_KEY=wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
AWS_SESSION_TOKEN=AQoEXAMPLEH4aoAH0gNCAPy...truncated...zrkuWJOgQs8IZZaIv2BXIa2R4Olgk

 {
 "mcpServers": {
 "awslabs.bedrock-kb-retrieval-mcp-server": {
 "command": "docker",
 "args": [
 "run",
 "--rm",
 "--interactive",
 "--env",
 "FASTMCP_LOG_LEVEL=ERROR",
 "--env",
 "KB_INCLUSION_TAG_KEY=optional-tag-key-to-filter-kbs",
 "--env",
 "BEDROCK_KB_RERANKING_ENABLED=false",
 "--env",
 "AWS_REGION=us-east-1",
 "--env-file",
 "/full/path/to/file/above/.env",
 "awslabs/bedrock-kb-retrieval-mcp-server:latest"
 ],
 "env": {},
 "disabled": false,
 "autoApprove": []
 }
 }
 }

NOTE: Your credentials will need to be kept refreshed from your host

Limitations

• Results with IMAGE content type are not included in the KB query response.

• The reranking parameter requires additional permissions, Amazon Bedrock model access, and is only available in specific regions.