Without a refresh token, every renewal depends on the original identity assertion and the IdP’s policy engine. When the access token expires, the client must re-present the assertion or obtain a new one from the IdP. That makes revocation more effective, but it also means latency, IdP outages, and policy changes can interrupt long running agent tasks.
Why token renewal becomes an availability and trust problem
When an enterprise agent must keep working for hours or days, the absence of a refresh token changes the reliability model. The agent is no longer holding a reusable renewal credential; instead, it depends on the original identity assertion and the IdP’s current policy decision each time the access token expires. That improves revocation leverage, but it also creates a hard dependency on the identity provider, the upstream assertion flow, and the policy state at renewal time. In agentic environments, that can turn routine expiry into an operational break point.
For security teams, the practical issue is not just whether the token can be renewed. It is whether the agent can survive policy drift, IdP latency, clock skew, and short-lived outages without stalling a business process. The control boundary is tighter, but the failure boundary moves closer to the runtime path. OWASP Top 10 for Agentic Applications 2026 is useful here because it frames agentic systems as execution environments that need explicit control over access, delegation, and failure handling. In practice, many security teams discover the operational cost of no-refresh-token designs only after long-running agent jobs begin failing at token expiry rather than during design review.
How repeated reauthorization changes the agent runtime
Without a refresh token, the agent cannot silently extend its session. Every new access token depends on some form of renewed authentication or delegated assertion exchange, and that means the agent’s continuity is tied to the identity provider’s availability and the freshness of the underlying trust decision. If the agent is acting on behalf of a person, that may be acceptable for short tasks. If the agent is acting as an enterprise workload, the same pattern can become fragile because the runtime assumes repeated success from a control plane that may not be designed for uninterrupted machine operation.
The operational effect is easiest to see in three places:
- Token expiry becomes a task boundary, not just a security setting.
- Policy changes can interrupt an in-flight workflow even if the agent was already active.
- IdP outages or higher latency can delay execution or force a hard stop.
This design is often used intentionally when organisations want stronger revocation, shorter abuse windows, and less value in a stolen bearer token. It also reduces the persistence value of a compromised session because there is no long-lived refresh credential to replay. But that benefit only holds if the renewal path itself is well governed and monitored. If the original assertion is weak, if renewal exceptions are poorly handled, or if the agent retries aggressively during an outage, the result can be repeated failure rather than safer continuity. NIST AI Risk Management Framework is relevant where the question is really about controlling autonomy, dependencies, and lifecycle risk in AI-enabled operations. Where the environment is built around human reauthentication rather than machine continuity, this guidance breaks down at scale.
When no-refresh-token designs are a good fit, and when they are not
Tighter renewal control often improves revocation and reduces credential replay exposure, requiring organisations to balance security gain against runtime fragility. That tradeoff is real, and there is no consensus that one pattern is universally better for every enterprise agent.
The pattern works best when the agent’s task window is short, the renewal path is cheap, and interruption is acceptable. It is also a strong fit when the organisation wants explicit reauthorisation for high-impact actions rather than indefinite delegated access. It is weaker when the agent must complete long workflows, operate across maintenance windows, or continue through IdP dependency outages. In those cases, the absence of a refresh token may create a failure mode that is operational rather than malicious: the agent simply cannot resume because renewal requires a live policy decision at the exact moment of expiry.
There is also a governance edge case. Some teams assume that removing refresh tokens automatically increases safety. That is only partly true. If the renewal path is poorly designed, organisations may compensate with oversized access tokens, exception handling, or manual reauthentication loops that create new exposure. The better question is whether the renewal model matches the task’s risk profile and recovery needs. For agentic access, OWASP Agentic AI Top 10 and MITRE ATLAS both help distinguish access-control fragility from broader adversarial abuse patterns. What works for a person’s interactive session is often the wrong model for a persistent enterprise agent.
Risk and Threat Considerations
The main risk is availability and control fragility, not just token expiry. If ongoing access depends on repeated reassertion of identity, the agent inherits the reliability of the identity provider, the policy engine, and the upstream assertion source. That can create a single point of failure for long-running automation, and it can also make policy changes take effect immediately in the middle of an operation.
Failure mechanism: When the access token expires, the client must obtain a new one through the original authorization path. If the IdP is slow, unavailable, or rejects the renewed assertion, the agent loses continuity. If the agent retries too aggressively or caches assumptions about prior approval, it can amplify load or keep failing until human intervention restores the flow.
Impact: Long-running jobs can halt, stateful workflows can desynchronise, and mission-critical automations can miss deadlines or partial-completion checkpoints. In some environments, the stronger revocation model is worth that tradeoff; in others, the renewal dependency becomes an operational bottleneck that effectively governs uptime.
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 and OWASP Non-Human Identity Top 10 address the attack surface, NIST AI RMF set the technical controls, and ISO/IEC 42001:2023 define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Agentic AI Top 10 | A1 — Agentic Access Control | Covers delegated agent access and renewal failure in autonomous workflows. |
| Recommendation — Constrain agent renewals to explicit trust decisions and deny silent continuity. | ||
| OWASP Non-Human Identity Top 10 | NHI-01 — Secrets and Credential Management | Applies because the question centers on token lifecycle and renewal credentials. |
| Recommendation — Reduce standing access by limiting token lifetime and renewal authority. | ||
| NIST AI RMF | MAP — Measure | Relevant to assessing agent dependency, lifecycle risk, and operational resilience. |
| GOV — Govern | Fits governance of agent autonomy, authorization boundaries, and escalation rules. | |
| Recommendation — Measure expiry failures and renewal latency as a model-risk signal. Govern when an agent may continue only after fresh authorization. | ||
| ISO/IEC 42001:2023 | A.6 — AI Risk Treatment | Addresses AI governance decisions where agent continuity depends on policy control. |
| Recommendation — Document renewal failure handling as an AI risk treatment decision. | ||
Practitioner Guidance
What to prioritise: Treat the renewal path as part of the agent’s runtime design, not as an authentication detail. If the task must survive interruptions, the team should decide early whether reauthorization events are acceptable failure points or whether the workflow needs a different trust model.
What to verify: Confirm how the agent behaves at expiry, during IdP degradation, and after a policy change. The important test is not whether renewal works once, but whether the system fails cleanly, retries safely, and preserves workflow state when renewal is denied or delayed.
Practitioner takeaway: No refresh token usually means stronger revocation and tighter control, but the organisation is paying for that with higher dependency on live identity infrastructure. The right design is the one whose failure mode matches the business tolerance for interruption.
