SECURITY ATLAS / EVALUATION BRIEF
Amazon Bedrock AgentCore Policy
Research reviewed: 2026-10-18
https://atlasofsecurity.com/landscape/vendors/aws-agentcore-policy/

THE ATLAS TAKE
Amazon Bedrock AgentCore Policy is a distinct and useful control to evaluate when the requirement is authorizing tool actions through AgentCore Gateway. Cedar policies make principal, action and gateway resource explicit, with conditions that can encode business constraints. Atlas sees the architecture as promising because a disallowed action can remain disallowed even when a model follows a malicious instruction. That promise depends on gateway mediation, trustworthy policy inputs and appropriate downstream credentials. Content moderation, agent identity lifecycle and target-system authorization remain complementary responsibilities rather than automatic consequences of creating a policy engine.

SCOPE
This entry covers Policy with AgentCore Gateway, not the entire Bedrock portfolio. Calls that bypass the gateway need their own controls. Bedrock Guardrails is a separate content-inspection service, and neither product automatically grants appropriate downstream credentials.

WORTH A LOOK WHEN
AWS teams routing supported agent tools through AgentCore Gateway with explicit authorization requirements.

THINK TWICE WHEN
Agents retain an unrestricted direct route to the same privileged APIs outside the gateway.

IMPLEMENTATION
1. Inventory tool and bypass paths
List all target APIs, gateway routes and credentials that could reach them directly.

2. Use trusted policy context
Derive caller identity and business constraints from authoritative sources rather than editable model text.

3. Test policy changes as code
Exercise permitted, forbidden and boundary-value requests, then review target-side effects and administrative permissions.

OPERATING REALITY
Platform engineers maintain tool schemas, action identifiers and policy deployment while identity owners maintain trusted principals. Application teams must review changed tools and gateway targets. A policy engine needs careful tests around boundary values and request context, plus evidence that the downstream execution role cannot exceed the intended business authority.

COMMERCIAL CONSIDERATIONS
Confirm current Policy and Gateway metering, regions and quotas with AWS. Include target execution, logging and integration costs rather than treating policy authoring as the complete service.
- Policy/Gateway usage and selected deployment region
- Target compute, logging and supporting AWS services
- Policy engineering, schema maintenance and integration tests

EVALUATION PLAN / PROPOSED TESTS, NOT COMPLETED RESULTS
1. Allow and deny synthetic refunds around a fixed threshold
Acceptance evidence: Retain policy, structured request and target execution evidence.
Owner: __________  Pass criterion: __________
Observed result: __________  Evidence location: __________

2. Submit the same request with a different principal
Acceptance evidence: Show the authoritative identity used in the decision.
Owner: __________  Pass criterion: __________
Observed result: __________  Evidence location: __________

3. Attempt an authorized lab bypass route
Acceptance evidence: Document the independent target permission that prevents direct execution.
Owner: __________  Pass criterion: __________
Observed result: __________  Evidence location: __________

QUESTIONS FOR THE VENDOR
- Can the agent reach the same API without going through the gateway?
- Are policy inputs derived from trusted identity claims or editable model arguments?
- What privileges does the gateway execution role retain after a request is authorized?

EVIDENCE GAPS
- Atlas has not independently tested policy correctness or gateway resilience.
- Confirm supported targets, trusted context fields, current quotas and regional availability.

SOURCES
AWS: policy scope, principals, and actions (Documentation)
https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/policy-scope.html
AWS: deploy and enforce a gateway policy (Documentation)
https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/policy-getting-started.html
AWS: AgentCore policy permissions (Documentation)
https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/policy-permissions.html

Use synthetic fixtures in an authorized environment. Agree rollback and acceptance criteria before enforcement.
Documentation research and Atlas analysis. Independent hands-on effectiveness, effort, and complete price remain unassessed.