Implement on-behalf-of token exchange for multi-tenant agents with Amazon Bedrock AgentCore Gateway
Amazon Bedrock AgentCore Identity natively supports OAuth 2.0 Token Exchange (RFC 8693) to solve identity propagation issues in multi-tenant generative AI agents. The On-Behalf-Of (OBO) pattern preserves the original user's identity via the `sub` claim while binding the token to specific downstream audiences via the `aud` claim, enforcing cryptographic least privilege. AgentCore Gateway automatically intercepts tool calls and performs token exchanges against tenant-specific authorization servers
Analysis
TL;DR
- Amazon Bedrock AgentCore Identity natively supports OAuth 2.0 Token Exchange (RFC 8693) to solve identity propagation issues in multi-tenant generative AI agents.
- The On-Behalf-Of (OBO) pattern preserves the original user's identity via the
subclaim while binding the token to specific downstream audiences via theaudclaim, enforcing cryptographic least privilege. - AgentCore Gateway automatically intercepts tool calls and performs token exchanges against tenant-specific authorization servers, removing the need for custom exchange logic within the agent code.
- This approach mitigates the "confused deputy" problem by ensuring downstream APIs can independently validate tokens without blindly trusting the agent's service identity.
Why It Matters
This development addresses a critical security bottleneck in deploying enterprise-grade AI agents, specifically regarding secure identity management across multi-tenant environments. By standardizing on RFC 8693, AWS enables developers to build scalable agent architectures that maintain strict audit trails and granular access controls without complex custom authentication layers. This reduces the risk of privilege escalation and unauthorized data access, which are primary concerns for organizations adopting agentic workflows.
Technical Details
- Native RFC 8693 Support: Amazon Bedrock AgentCore Identity implements the OAuth 2.0 Token Exchange specification as a credential-provider grant type, allowing seamless integration with standard authorization servers like Okta.
- Claim Transformation: During the exchange, the inbound user token's
sub(subject) claim is preserved to identify the original caller, while theaud(audience) claim is rewritten to match the specific downstream API. Anact(actor) claim records the agent performing the action, separating authorization decisions from audit logging. - Gateway Interception: Bedrock AgentCore Gateway acts as an interceptor that identifies the target tenant and orchestrates the token exchange with the corresponding authorization server before the tool call is executed, keeping the agent code clean.
- Reference Implementation: The guide utilizes "TravelBot," a multi-tenant booking assistant serving tenants like Acme and Globex, demonstrating how distinct tokens are issued for each tenant's booking API to prevent cross-tenant token reuse.
Industry Insight
- Adopt Standardized Token Exchange: Organizations building multi-agent systems should prioritize RFC 8693 compliance to ensure interoperability with existing identity providers and reduce custom security overhead.
- Shift Security Left in Agent Design: Developers must design agent architectures with identity propagation in mind from the start, leveraging gateway-level interception rather than embedding authentication logic within individual agent models.
- Auditability as a Feature: The separation of
sub(user) andact(agent) claims provides a robust framework for compliance and forensic analysis, making it easier to demonstrate regulatory adherence in AI-driven business processes.
Disclaimer: The above content is generated by AI and is for reference only.