check_trust

THE RISK

Low Risk

Why check_trust needs a policy

The name 'check_trust' implies a verification or status-checking function, which would fall under Read category. However, with no description provided, confidence is substantially reduced. Given the context of an AgentOS server managing policy-compliant agents, this tool likely performs trust validation checks (a read operation).

From the tool's definition Tool name 'check_trust' suggests a query operation, but description is empty making direct assessment difficult.

Documented attack patterns abuse exactly the kind of access check_trust gives an agent:

POLICY

How to control check_trust

PolicyLayer is an MCP gateway — it sits between your AI agents and Agentos, and nothing reaches the server without passing your rules. This is the rule we recommend for check_trust:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "check_trust": {}
  }
}

check_trust is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Agentos — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

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Free to start. No card required.

EXPLORE

Related tools and policies

More Agentos tools

Execute deploy_agent Deploy an agent to start execution. Deployment environments: - local: Runs on your machin Execute agt_policy_check_text Run AGT poisoning, MCP, and prompt-defense checks against arbitrary text. Execute establish_handshake Initiate a trust handshake with a peer agent. Creates a cryptographic challenge, reco Write attach_policy Attach safety policies to an agent. Policies enforce rules and constraints on agent behavi Write create_agent Create a new AI agent from a natural language description. The agent will be configured wi Write create_policy Create a custom policy from a natural language description. Policies define rules that ag Write record_interaction Record an interaction outcome to update trust scores. Valid outcomes: success, failur Write request_approval Request human approval for a sensitive agent action. Use this when: - Policy requires hum

All 18 Agentos tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

Roll out MCP under one policy → Per-person scoped tokens, one central policy, and full audit across every server your team connects.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →
PolicyLayer vs alternatives → How deterministic, per-call MCP policy compares with gateways, identity layers, and authorisation platforms.

FAQ

Questions about check_trust

What does the check_trust tool do? +

check_trust. It is categorised as a Read tool in the Agentos MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on check_trust? +

Register the Agentos MCP server in PolicyLayer and add a rule for check_trust: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Agentos. Nothing to install.

What risk level is check_trust? +

check_trust is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit check_trust? +

Yes. Add a rate_limit block to the check_trust rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block check_trust completely? +

Set action: deny in the PolicyLayer policy for check_trust. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides check_trust? +

check_trust is provided by the Agentos MCP server (@microsoft/agentos-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Agentos tool call.

Start from Agentos, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →