aws-bedrock-mcp-server

MCP server for AWS Bedrock Knowledge Base — exposes two tools for semantic search and RAG.

| Tool | Description | |------|-------------| | bedrock_retrieve | Semantic / hybrid search — returns raw passages from the Knowledge Base | | bedrock_retrieve_and_generate | Full RAG pipeline — retrieves passages and generates a grounded answer |

Usage with Claude Code

claude mcp add aws-bedrock -- npx -y @miguel-carrera/aws-bedrock-mcp-server

Or add to your claude_desktop_config.json / .mcp.json:

Cognito auth (recommended):

{
  "mcpServers": {
    "aws-bedrock": {
      "command": "npx",
      "args": ["-y", "@miguel-carrera/aws-bedrock-mcp-server"],
      "env": {
        "BEDROCK_KNOWLEDGE_BASE_ID": "<your-kb-id>",
        "AWS_REGION": "us-east-1",
        "COGNITO_IDENTITY_POOL_ID": "<identity-pool-id>",
        "COGNITO_USER_POOL_CLIENT_ID": "<app-client-id>",
        "COGNITO_DOMAIN": "<your-domain>.auth.us-east-1.amazoncognito.com"
      }
    }
  }
}

AWS profile auth:

{
  "mcpServers": {
    "aws-bedrock": {
      "command": "npx",
      "args": ["-y", "@miguel-carrera/aws-bedrock-mcp-server"],
      "env": {
        "BEDROCK_KNOWLEDGE_BASE_ID": "<your-kb-id>",
        "AWS_REGION": "us-east-1",
        "AWS_PROFILE": "default"
      }
    }
  }
}

Prerequisites

• Node.js ≥ 18

For AWS profile auth: credentials configured in ~/.aws/credentials or ~/.aws/config.

For Cognito auth: a Cognito User Pool with a hosted UI and an Identity Pool. On the first run the server opens your browser to log in; credentials are cached to ~/.atlas-ai/cognito-credentials.json and reused until they expire (~1 hour).

Required IAM permissions:

{
  "Effect": "Allow",
  "Action": [
    "bedrock:Retrieve",
    "bedrock:RetrieveAndGenerate"
  ],
  "Resource": "arn:aws:bedrock:*:*:knowledge-base/*"
}

Configuration

| Environment variable | Required | Default | Description | |---|---|---|---| | BEDROCK_KNOWLEDGE_BASE_ID | Recommended | — | Default Knowledge Base ID; can be overridden per tool call | | AWS_REGION | No | us-east-1 | AWS region where your Knowledge Base lives | | Cognito auth | | | | | COGNITO_IDENTITY_POOL_ID | Yes (Cognito) | — | Cognito Identity Pool ID — activates Cognito auth when set | | COGNITO_USER_POOL_CLIENT_ID | Yes (Cognito) | — | Cognito User Pool app client ID | | COGNITO_DOMAIN | Yes (Cognito) | — | Cognito hosted UI domain (e.g. xyz.auth.us-east-1.amazoncognito.com) | | AWS profile auth | | | | | AWS_PROFILE | No | default | AWS named profile from ~/.aws (used when COGNITO_IDENTITY_POOL_ID is not set) |

Tools

bedrock_retrieve

Search the Knowledge Base and return raw passages.

| Parameter | Type | Default | Description | |---|---|---|---| | query | string | — | Natural language search query (required) | | knowledge_base_id | string | env var | Bedrock KB ID | | number_of_results | number | 5 | Passages to return (1–100) | | search_type | SEMANTIC | HYBRID | SEMANTIC | Search strategy | | next_token | string | — | Pagination cursor | | response_format | markdown | json | markdown | Output format |

bedrock_retrieve_and_generate

Retrieve passages and generate a grounded answer using a Bedrock model.

| Parameter | Type | Default | Description | |---|---|---|---| | query | string | — | Question to answer (required) | | knowledge_base_id | string | env var | Bedrock KB ID | | model_arn | string | Claude 3 Haiku | ARN of the Bedrock model for generation | | number_of_results | number | 5 | Passages to retrieve (1–100) | | search_type | SEMANTIC | HYBRID | SEMANTIC | Search strategy | | session_id | string | — | Session ID for multi-turn conversations | | system_prompt | string | — | Custom generation prompt (use $search_results$ placeholder) | | response_format | markdown | json | markdown | Output format |

Development

npm install
npm run dev      # watch mode
npm run build    # compile to dist/