This record as markdown: /tools/io-github-portel-dev-ncp/delete-key.md
What delete_key does on Ncp
AI agents call delete_key to permanently remove resources in Ncp, typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
Why delete_key is rated Critical
Deleting a Redis key permanently removes data from the cache/store with no built-in undo mechanism. This is an irreversible operation that could cause data loss or service degradation if misused by an AI agent (e.g., deleting critical session keys, cache entries, or configuration). High severity due to potential blast radius in production systems relying on Redis.
From the tool's definition Tool name is 'delete_key' and description states 'Delete Redis key' — the verb 'Delete' combined with the fact that Redis key deletion is irreversible makes this a destructive operation.
Attacks that exploit this kind of access
The rule that runs delete_key safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Ncp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For delete_key, this is the rule to start with:
delete_key is removed from the agent's tool list entirely, so the agent never calls it. The rest of the server keeps working.
The button opens the PolicyLayer dashboard: create your workspace, connect Ncp, apply this rule, and every delete_key call is checked against it from then on.
Questions about delete_key
Delete Redis key. It is categorised as a Destructive tool in the Ncp MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Ncp MCP server in PolicyLayer and add a rule for delete_key: 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 Ncp. Nothing to install.
delete_key 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 delete_key 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 delete_key. 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.
delete_key is provided by the Ncp MCP server (@portel/ncp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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