A bounded agent evaluates the user and the agent together, so the final permission set is the overlap of both. A shared integration identity evaluates only the integration, which means the acting user disappears from the control plane. The first model preserves delegation boundaries; the second silently pools access across users.
Why the distinction matters in practice
A bounded agent keeps the user and the acting agent visible as separate control inputs. That matters because the security decision can reflect both the requester’s entitlements and the agent’s own standing, which preserves delegation boundaries and makes least privilege enforceable at the point of action.
A shared integration identity collapses that distinction. The control plane sees the integration as the actor, so access is pooled across everyone who can drive it. That can simplify wiring, but it also makes it much harder to answer who really had the authority to do what, and under what conditions.
One useful way to think about the difference is that bounded delegation answers, “what may this user ask this agent to do?”, while a shared integration identity answers, “what may this integration do for anyone who can reach it?” The first is a policy problem with a user context; the second is a transport or credential problem with weaker attribution.
How permission evaluation changes
In a bounded model, permission is computed from two sides: the caller’s rights and the agent’s allowed envelope. That means the effective action set shrinks to the overlap, which is the main defense against accidental privilege amplification when an agent has broad tool access.
In a shared integration identity, the user-specific boundary disappears from the enforcement decision. If several users invoke the same integration, the system usually cannot distinguish whether a particular action was appropriate for one user but not another, unless you add separate approval, token exchange, or explicit policy checks around the handoff.
This is why shared integration identities often become hidden superusers over time. The integration may start as a convenience layer, but once it is reused across teams or workflows, its effective access tends to reflect the most permissive use case rather than the most constrained one.
Delegation, auditability, and control-plane visibility
The bounded model is stronger when you need clean delegation records, scoped approvals, or per-user accountability. It supports a clearer audit trail because the agent acts within a defined relationship to the originating user, rather than as an anonymous broker for many users.
Shared integration identities are easier to operationalise, but they weaken attribution. If the same credential or service identity is reused across users, you may still log an action, yet the logs often show the integration rather than the human or workload that triggered the action. That makes review, incident response, and access recertification harder.
For that reason, regulatory and audit perspectives on NHI governance are often a better fit for the shared-identity model than for the bounded one, because the central issue is ownership, traceability, and control over reused machine access.
Risk and Threat Considerations
Shared integration identities create concentration risk: one credential, token, or connection path can expose many users’ activity and many downstream systems at once. That raises the blast radius of misuse, makes overprivilege easier to miss, and can let an attacker hide inside apparently legitimate integration traffic.
Failure mechanism: When the acting user is not preserved in the control plane, the integration’s standing privilege becomes the effective privilege for every caller. That enables privilege pooling, weak attribution, and lateral abuse if the shared identity is compromised or granted too much access.
Impact: A single compromised integration can authorize actions that were never intended for all users, and investigators may struggle to prove which user, workflow, or request path was responsible. The result is higher blast radius, poorer accountability, and slower containment.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 addresses the attack and risk surface, while NIST SP 800-53 Rev 5 sets the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | IA-9 — Identification and Authentication (Service-to-Service) | Covers mutual authentication for integrations acting between systems. |
| AC-6 — Least Privilege | Applies because pooled integration access can exceed any one user's need. | |
| AU-2 — Event Logging | Relevant because delegated vs shared identity changes who must be attributable in logs. | |
| Recommendation — Bind each integration to a distinct authenticated service identity. Constrain shared integrations to the minimum permissions needed for each task. Log the originating user and the acting integration separately where possible. | ||
| OWASP Non-Human Identity Top 10 | NHI-05 — Overprivileged NHI | Shared integration identities often accumulate more access than any single user requires. |
| NHI-10 — Human Use of NHI | The question centers on whether humans are acting through a shared non-human identity. | |
| Recommendation — Review shared integrations for privilege that exceeds the narrowest legitimate use case. Prevent humans from reusing a single integration identity as a proxy for many users. | ||
Practitioner Guidance
What to verify: Confirm whether the authorization layer can still distinguish the originating user from the integration identity at enforcement time, not just in logs. If it cannot, treat the design as shared-credential governance, not delegated access governance.
Decision rule: Use bounded delegation when the action meaningfully depends on user context, approval state, or per-user entitlement. Use a shared integration identity only when the business truly accepts pooled authority and you have compensating controls for scope, review, and revocation.
What practitioners underestimate: The convenience of a shared integration identity often masks a governance debt that surfaces later as access sprawl, weak non-repudiation, and difficult offboarding. Once multiple teams depend on the same integration, disentangling authority is usually harder than building it correctly up front.
Practitioner takeaway: If you need to preserve who is acting on whose behalf, keep the user in the control plane; if you remove that relationship, you must assume pooled privilege and design for it explicitly.
Related resources from NHI Mgmt Group
- What is the difference between human identity governance and AI agent governance?
- What is the difference between workload identity and API keys for AI agents?
- What is the difference between governing human access and governing AI agent access?
- What is the difference between shared service-account access and cryptographically verifiable agent identity?