Runtime Security for Agentic AI
AI Agent Access Control on Every Tool Call
PromptHalo sits inline on every inference, tool call, and agent handoff. Each action gets an allow, restrict, challenge, deny, or monitor decision in under 100ms.
- Signed agent passports with budget, scope and authority decay
- Block out-of-scope tool and API calls before they run
- Live in under a day, with no model retraining or code rewrite
Decision logs mapped to OWASP LLM Top 10, NIST AI RMF and the EU AI Act
Talk to us about agent access control
Tell us about your agents and what they can touch. A member of our team will follow up by email.
Why security teams use PromptHalo to control agent access
Authority is enforced outside the agent
Access is scoped per action and enforced externally. An agent cannot grant itself more access than you gave it.
A decision on every action
Septa runs inline on every inference, tool call and agent-to-agent handoff and returns allow, restrict, challenge, deny or monitor in under 100ms.
Agent passports that expire
Each agent carries a signed security passport with risk profiling, authority decay, and budget and scope limits, so access does not live forever.
Fewer false alarms for your team
ML-based detection catches over 95% of attacks at under 5% false positives, against roughly 35% catch and 15-20% false positives for rule-based checks.
Fits your stack, not the other way round
Connect through API gateway, agent mode or inline middleware. No model retraining, no code rewrite, and no access to your proprietary models.
Evidence your auditors can replay
Every decision is written append-only and tamper-evident with its reason, agent identity, session and timestamp, mapped to OWASP LLM Top 10, NIST AI RMF and the EU AI Act.
What AI agent access control looks like in practice
Agents call tools, pull from RAG sources and hand work to other agents. Firewalls, DLP and code scanners were never built to see those actions. PromptHalo puts one trust check in front of each one and decides, in under 100ms, whether it should run.
Litmus attacks your agents, RAG layers and tool chains the way an adversary would and turns what it finds into runtime defenses through a shared Threat Library. Septa then enforces those rules on every action, so protection gets stronger as you scale.
- Allow, restrict, challenge, deny or monitor decisions on each agent action
- Signed agent security passports with risk profiling and authority decay
- Budget and scope limits across time, steps and risk, with re-authorization when an envelope is exceeded
- Blocking of unintended, out-of-scope or dangerous tool and API calls
- Prompt injection, jailbreak and RAG poisoning detection using Threat Library signatures and classifier scoring
- Data leakage prevention across multi-step and multi-session conversations
- Behavioral drift detection across sessions using per-tenant session and memory state
- A configurable policy engine so you can flag, log or block responses with your own rules
- Agentic Commerce Trust for shopper agents across catalog, cart, checkout, payments and refunds, at design-partner stage
What happens after you send the form
Tell us about your agents
We look at what your agents do, which tools, APIs and data they touch, and where they run today.
See a live walkthrough
We show passports, budgets, scope limits and enforcement decisions against your own use case.
Pick a deployment path
Choose API gateway, agent mode or inline middleware. Deployment takes under a day with no code rewrite.
Frequently asked questions
How is this different from normal identity and access management?
IAM controls who signs in. PromptHalo controls what an agent may do at each step: every inference, tool call and agent-to-agent handoff gets its own decision, with scope and budget enforced outside the agent. It is purpose-built for the agentic attack surface that firewalls, DLP and code scanners were never designed to see.
Will access checks slow my agents down?
Septa makes its allow, restrict, challenge, deny or monitor decision in under 100ms per action. For commerce surfaces, the Agentic Commerce Trust check authorizes, scores and decides in under 50ms.
Do you need access to our models?
No. PromptHalo is model- and vendor-agnostic and works without access to your proprietary models. There is no model retraining and no code rewrite.
How long does it take to get running?
Under one day. You can connect through API gateway integration, agent or orchestration mode, or an inline middleware SDK. All three feed the same inspection and enforcement pipeline.
Can we write our own access rules?
Yes. The policy enforcement engine lets you define custom rules to flag, log or block in real time, applied per action, with each outcome recorded for later review.
What does it cost?
Pricing is not published. Tell us how many agents you run, which tools they call and how you want to deploy, and we will put a quote together for your setup.
See agent access control on your own agents
Send us a few details about your agentic AI setup. We will walk you through passports, scope limits and inline enforcement, then map out a deployment path that fits your stack.
- Signed agent passports with budget, scope and authority decay
- Block out-of-scope tool and API calls before they run
- Live in under a day, with no model retraining or code rewrite