Delegated user authorization ties each action to a specific user’s existing permissions and narrows what the agent can do at runtime. Broad shared credentials give the system a wider standing capability that is harder to justify, monitor, and contain. For agent workflows, delegated authorization is safer because access stays scoped, attributable, and easier to revoke or review.
How delegated authorization changes what an AI agent can do
Delegated user authorization means the agent acts with a user-scoped allowance, not a blanket system-level capability. The practical difference is that the agent inherits only the permissions needed for the current task, so the runtime decision stays tied to a real principal, a narrower blast radius, and a clearer approval boundary.
That matters because agent workflows are not just about whether an action is technically possible, they are about whether the action is justified for this user, this session, and this task. The right model keeps access bounded and makes it easier to explain why a specific write, query, or transaction happened.
Broad shared credentials work differently: they collapse many actions into one standing secret or token, which makes the agent look more capable than the user who triggered it. Once that happens, every downstream action is harder to separate from the operator, harder to expire cleanly, and harder to reason about as an access decision rather than a system convenience.
Why broad shared credentials are a different security shape
Shared credentials are not just a weaker version of delegation, they change the trust model. A shared credential typically grants standing power that survives beyond one user session, one task, or one approval event, so the control problem shifts from “what is this user allowed to do?” to “who can use the shared secret, and when did it last get exposed?”
For agent systems, that creates a larger containment problem. If the credential is copied, reused, or embedded in tooling, it can be exercised outside the intended workflow, and the same access path may be reused across users, environments, or automations.
That is why shared credentials usually create more monitoring debt. The activity may be visible in logs, but attribution is weak because the secret represents the system, not the user, and revocation often has broader side effects than simply disabling one user’s delegated grant.
What practitioners should compare before choosing the model
The real comparison is not “delegation versus convenience,” but “per-action accountability versus standing power.” delegated authorization is the better default when the agent is acting on behalf of a person, when the action has business impact, or when you need to prove who approved the operation after the fact.
Shared credentials are sometimes used for legacy integrations or tightly controlled service flows, but they should be treated as a constrained exception. If a workflow can be redesigned so the agent receives a scoped, revocable, user-linked authorization instead of a durable shared secret, that is usually the safer architecture.
In agentic systems, the distinction also affects how you design escalation. A delegated model can let the agent request more access only when needed, while a shared-credential model tends to front-load excess privilege so the workflow does not break later. That trade-off usually favors the wrong side of least privilege.
Risk and Threat Considerations
Broad shared credentials increase the chance of overreach, abuse, and hard-to-contain compromise because one standing secret can unlock more action than any single user intended. In agent workflows, that can turn a narrow task into an environment-wide access problem if the credential is reused, leaked, or accepted by multiple tools.
Failure mechanism: The credential becomes a persistent capability rather than a user-specific authorization grant, so compromise, reuse, or misrouting can authorize actions outside the original business context.
Impact: You lose attribution, revocation becomes blunt, and any misuse can spread across sessions or automations instead of ending with one user’s permission boundary.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Agentic AI Top 10, OWASP Non-Human Identity Top 10 and OWASP API Security Top 10 address the attack and risk surface, while NIST SP 800-53 Rev 5 and NIST Zero Trust (SP 800-207) set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Agentic AI Top 10 | ASI03 — Identity & Privilege Abuse | Delegated vs shared access is an agent privilege boundary question. |
| Recommendation — Scope agent authority per action and avoid standing access that outlives the user task. | ||
| OWASP Non-Human Identity Top 10 | NHI-05 — Overprivileged NHI | Shared agent credentials can grant broader standing privilege than needed. |
| Recommendation — Reduce agent access to the minimum permissions required for the task. | ||
| NIST SP 800-53 Rev 5 | AC-6 — Least Privilege | The question is fundamentally about limiting what the agent can do. |
| IA-5 — Authenticator Management | Shared credentials and delegated tokens both depend on controlled credential lifecycle. | |
| IA-9 — Service Identification and Authentication | AI agents often authenticate as services or workloads when using shared credentials. | |
| Recommendation — Limit each agent action to the minimum necessary permissions. Manage issuance, rotation, and revocation so credentials do not become standing access. Use identity-specific authentication instead of reusable shared secrets where possible. | ||
| NIST Zero Trust (SP 800-207) | ZTA — Zero Trust Architecture | The comparison maps to verifying each action and removing standing trust. |
| Recommendation — Verify each request and remove standing privilege from agent workflows. | ||
| OWASP API Security Top 10 | API5 — Broken Function Level Authorization | Agent actions that exceed the caller's rights resemble function-level authorization failure. |
| API2 — Broken Authentication | Shared credentials weaken assurance about who is actually acting. | |
| Recommendation — Enforce per-function authorization checks on every agent-operated action. Bind authentication to the real principal so actions remain attributable. | ||
Practitioner Guidance
What to verify: Confirm whether the agent receives a user-linked, task-scoped authorization at runtime or a reusable shared secret that outlives the session. If the same credential can be used by multiple workflows or operators, treat that as a design smell, not a convenience feature.
Decision rule: If the agent is performing an action that should be explainable, revocable, or approval-bound, prefer delegated authorization. Reserve shared credentials for cases where there is no viable delegation path and you can compensate with tight isolation, short lifetime, and strong monitoring.
Practitioner takeaway: The safer design is the one that preserves the user boundary all the way through the agent’s action, because that is what keeps access understandable, reviewable, and containable when something goes wrong.
Related resources from NHI Mgmt Group
- What is the difference between managed identities and hardcoded secrets for AI agents?
- What is the difference between workload identity and API keys for AI agents?
- What is the difference between logging actions and logging intent for AI agents?
- What is the difference between delegated user access and machine authority for AI agents?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 30, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
