AI agents call pass__list_vaults to retrieve information from Proton-MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and returns information about available vaults without creating, modifying, deleting, or executing any operations. It is a simple enumeration/listing operation typical of Read category tools. Severity is low because listing vault metadata has minimal blast radius—it reveals structure but not vault contents themselves, and causes no state change.
From the tool's definition Tool name 'pass__list_vaults' combined with description 'List available Proton Pass vaults' indicates a retrieval operation with no side effects.
Documented attack patterns abuse exactly the kind of access pass__list_vaults gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Proton-MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for pass__list_vaults:
{
"version": "1",
"default": "deny",
"tools": {
"pass__list_vaults": {}
}
}pass__list_vaults is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
List available Proton Pass vaults. It is categorised as a Read tool in the Proton-MCP MCP Server, which means it retrieves data without modifying state.
Register the Proton- MCP server in PolicyLayer and add a rule for pass__list_vaults: 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 Proton-MCP. Nothing to install.
pass__list_vaults is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the pass__list_vaults 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.
Set action: deny in the PolicyLayer policy for pass__list_vaults. 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.
pass__list_vaults is provided by the Proton- MCP server (jorgenclaw/proton-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Proton-MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
36 Proton-MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.