How do I prevent AWS Bedrock agents from over-executing?

AWS Bedrock Agents execute action groups with the full permissions of their attached IAM role — and if that role is over-permissioned (which most are), the agent can perform any action the role allows, regardless of the user's intent.

Bedrock Agents connect to your AWS infrastructure through Action Groups backed by Lambda functions. The security model relies entirely on IAM roles:

• Broad IAM roles: Most Bedrock agents run with roles that have far more permissions than any single task requires
• No intent validation: The agent can invoke any action group — there's no policy layer between the LLM's decision and the Lambda execution
• Knowledge base data exposure: Agents with RAG access can query across all indexed documents regardless of user authorization
• Session-level permissions: Permissions are scoped to the session, not to individual actions within the session

AWS recommends least privilege but provides no tooling to enforce it at the action level within Bedrock Agents.

Exogram adds a governance layer between Bedrock's action decision and Lambda execution. Each action group call is intercepted, evaluated against deterministic policy rules, and either permitted or blocked — in 0.07ms. Your IAM role stays broad for operational flexibility. Exogram enforces the fine-grained constraints.