Amazon Bedrock AgentCore Gateway can be configured for an on-behalf-of (OBO) token exchange with Microsoft Entra ID, enabling an AI agent to call the ServiceNow REST API while preserving the calling user’s identity, according to the post. It says that without identity propagation, API calls arrive at downstream services as the application itself rather than the user who initiated the action, breaking audit trails, bypassing user-level access controls, and violating the principle of least privilege. The architecture connects an AI agent application protected by Microsoft Entra ID through an OAuth application registration, a Model Context Protocol (MCP) server implemented using AgentCore Gateway between the agent and ServiceNow, and the ServiceNow REST API configured with an inbound OAuth integration tied to Microsoft Entra ID. In the flow, the user acquires a JSON Web Token (JWT) to invoke the agent; the agent authenticates to the gateway with a JWT token scoped to the agent’s own application registration; the gateway exchanges that token using the OBO flow for a new token scoped to the ServiceNow API connector with the original user’s identity preserved; and ServiceNow receives a valid token whose preferred_username claim maps to an existing ServiceNow user and applies that user’s permissions. The post states the pattern can be applied to other REST APIs protected by OAuth and that in production identity propagation can be paired with Amazon Bedrock Guardrails.