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AI agent security check: your risk score in 20 questions

An AI agent is riskier the more it acts without approval, outside a sandbox, with over-broad keys and unchecked extensions. Answer 20 questions: you get a risk score out of 100 and the list of fixes, from most to least urgent.

Isolation

Does the agent run in a sandbox (container, virtual machine or dedicated system account)?
Is its file access limited to the folders it needs?
Is its web interface or API unreachable from the internet, or protected (strong password, VPN)?
Are its outbound connections limited to an allow-list of domains?

Actions and instructions

Do the shell commands it runs require your approval?
Do irreversible actions (deletion, sending email, payment, publishing) require confirmation?
Have you set guardrails against instructions hidden in the pages, emails and documents it reads?
If it answers on a messaging app, does it only obey an allow-list of contacts?

Secrets and data

Are keys and passwords kept out of the files the agent reads (environment variables, secrets vault)?
Are the API keys dedicated to the agent, with limited rights and a spending cap?
Does sensitive data stay with you (local model, or a provider with no data retention)?

Extensions (MCP, skills)

Do the installed MCP servers come from verified sources (official vendor, reviewed code)?
Did you read the skills and plugins before installing them?
Have you enabled only the MCP servers and skills you actually use?
Are their versions pinned (no automatic update without review)?

Monitoring and recovery

Are the agent's actions logged and reviewed from time to time?
Are the agent and its dependencies updated regularly?
Are the files the agent can modify backed up or versioned?
Is a cost alert or cap in place?
Do you know how to stop the agent immediately (stop command, key revocation)?

How to use it

Answer the twenty questions for the agent you use, whether it is a personal assistant, a coding agent, an automation workflow or an agent that drives the browser. The score is computed with every answer, with nothing sent: your answers stay in your browser and disappear when you close the page.

  • Yes: the protection is in place and you have checked it.
  • No or Don't know: both count as a risk. Not knowing whether the agent can run a command without asking is already a gap.
  • Not applicable: offered only when the question may not apply (no messaging, no MCP server, no exposed interface…). It does not count.

The result gives a risk score out of 100 (0 = all protections in place), a level, and the list of fixes to make, from most to least important, with a link to the relevant guide or definition when the site has one.

The method: 20 weighted protections

Each question is worth a number of points; the total is 100. The score adds up the points of missing or unknown protections. The weights are an editorial choice: the more a measure prevents serious, irreversible damage, the more it weighs. The six heaviest:

  • 8 — Run the agent in a container, a virtual machine or a dedicated system account, with no access to your main session.
  • 8 — Turn on command approval; only pre-approve read-only commands.
  • 7 — Limit the agent to a working folder; never your whole home folder, your SSH keys or your backups.
  • 7 — Don't expose the agent's dashboard to the internet: listen on localhost, access through a VPN or authenticated tunnel.
  • 7 — Require human confirmation for anything that can't be undone: deletion, sending, payment, publishing.
  • 7 — Treat all content read as data, never as orders: explicit instruction, separate reading and acting tools, approval before any action triggered by outside content.

The level follows three bands: 0 to 20, low risk; 21 to 50, moderate risk; above 50, high risk. The questions cover five families: isolation (sandbox, folders, network, exposure), actions (approval with a human in the loop, prompt injection, messaging), secrets and data (least privilege, dedicated keys, local model), extensions (MCP servers, skills) and monitoring (logs, updates, backups, emergency stop).

Why these protections

An AI agent is not just a chatbot: it acts. It reads files, runs commands, sends messages, calls services with your keys. The main risk doesn't come from a malicious AI but from two very ordinary causes: a misreading (the agent deletes the wrong folder) and an instruction hidden in content it reads (a web page, an email or a document asking it to send your files elsewhere). The second one, prompt injection, has no complete defence today: that is why most questions are about limiting damage rather than preventing it.

The worst danger appears when three conditions combine: the agent has access to private data, it reads outside content, and it can communicate outward. Removing just one of the three breaks the data exfiltration chain. The questions on outbound network, messaging and folders serve that purpose. They overlap with the risks described by the OWASP Top 10 for LLM Applications 2025: prompt injection, sensitive information disclosure, supply chain, excessive agency and unbounded consumption.

Extensions form the agent's supply chain: an MCP server or a skill installed without review can contain instructions or code that run with your rights. The guide Choosing an MCP server explains how to sort them. For a step-by-step setup, see Secure an AI agent.

Limits of the check

  • It is a self-assessment. The score is only as good as your answers; it doesn't replace a security audit or a penetration test.
  • The weights are choices. An agent that only touches a drafts folder doesn't have the same stakes as one that pays invoices: read the result in light of what it can break.
  • A low score is not a guarantee. No combination of settings makes an agent immune to prompt injection; it reduces the consequences.
  • Run it again. After each new extension, new access or model change, the risk profile changes. Method reviewed on October 25, 2026.

Sources

Frequently asked questions

How do I know if my AI agent is secure?

Check three things first: it runs isolated (sandbox), it asks for your approval before irreversible actions, and it only has the access it needs. The check reviews twenty protections and gives a score out of 100.

What is prompt injection?

An instruction hidden in content the agent reads (web page, email, document) that it takes as an order. It can push it to leak data or act on your behalf.

Are my answers stored?

No. The calculation happens in your browser; nothing is sent or kept.

Why does “don't know” count as a risk?

Because a protection whose state you don't know doesn't protect you: permissive defaults are common. Check the agent's documentation, then run the check again.

What score should I aim for?

20 or less for an agent with access to your accounts, files or money. Between 21 and 50, the agent can be used on low-stakes tasks while you fix the rest.

Neutrality. No affiliate links. No vendor pays to be reviewed, rated or ranked. Reviews are directed by François Chollet, neutral and factual, and every data point is dated and sourced. How we score