Amazon describes fine-grained access control for Bedrock Managed Knowledge Base tools using AgentCore Gateway
Amazon published a design and sample implementation showing how to prevent LLM-driven agents from accessing data a user isn’t authorized to see by injecting verified user attributes at the AgentCore Gateway and scoping searches with Bedrock Managed Knowledge Base ACL awareness. The pattern uses JWTs (via Amazon Cognito), a gateway request interceptor (AWS Lambda), Policy in AgentCore with Cedar evaluation, and resource-based role restrictions to enforce userContext when exposing the knowledge base as MCP tools.