Remove a user or user-override ticker entry. Bundled defaults cannot be removed; removing a user-override reverts the entry back to its bundled default. Persists the change to {dataRoot}/market/underlyings.json.
AI agents call unregister_underlying to permanently remove resources in Tradeblocks — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
An AI agent that decides to call unregister_underlying doesn't hesitate, doesn't double-check, and doesn't stop at one. Whatever it removes from Tradeblocks is gone — there is no undo for destructive operations.
Attacks that exploit this kind of access
Remove a user or user-override ticker entry. Bundled defaults cannot be removed; removing a user-override reverts the entry back to its bundled default. Persists the change to {dataRoot}/market/underlyings.json. It is categorised as a Destructive tool in the Tradeblocks MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Tradeblocks MCP server in PolicyLayer and add a rule for unregister_underlying: 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 Tradeblocks. Nothing to install.
unregister_underlying is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the unregister_underlying 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 unregister_underlying. 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.
unregister_underlying is provided by the Tradeblocks MCP server (tradeblocks-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.