Cancel an active offer you made on an ENS name. Returns unsigned Seaport cancel() calldata. Only the bidder (the order's offerer) can cancel. If the offer was cross-posted to OpenSea, you signed a second 'opensea' variant — pass BOTH order hashes as alsoCancel so one tx kills both. Cancelling rel...
Part of the Name Whisper — ENS Intelligence Layer server.
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AI agents may call cancel_offer to permanently remove or destroy resources in Name Whisper — ENS Intelligence Layer. Without a policy, an autonomous agent could delete critical data in a loop with no way to undo the damage. PolicyLayer blocks destructive tools by default and requires explicit human approval before enabling them.
Without a policy, an AI agent could call cancel_offer in a loop, permanently destroying resources in Name Whisper — ENS Intelligence Layer. There is no undo for destructive operations. PolicyLayer blocks this tool by default and only allows it when a human explicitly approves the action.
Destructive tools permanently remove data. Block by default. Only enable with explicit approval workflows.
{
"version": "1",
"default": "deny",
"hide": [
"cancel_offer"
]
}See the full Name Whisper — ENS Intelligence Layer policy for all 42 tools.
These attack patterns abuse exactly the kind of access cancel_offer gives an agent. Each links to the full case and the policy that stops it:
Other destructive tools across the catalogue. The same approach applies to each: deny by default, or require human approval.
Cancel an active offer you made on an ENS name. Returns unsigned Seaport cancel() calldata. Only the bidder (the order's offerer) can cancel. If the offer was cross-posted to OpenSea, you signed a second 'opensea' variant — pass BOTH order hashes as alsoCancel so one tx kills both. Cancelling releases the WETH you'd committed to the offer — the buyer's wallet keeps its WETH balance free to bid elsewhere once the Seaport order is invalidated. For cancelling your own listings, use cancel_listing.. It is categorised as a Destructive tool in the Name Whisper — ENS Intelligence Layer MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Name Whisper — ENS Intelligence Layer MCP server in PolicyLayer and add a rule for cancel_offer: 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 Name Whisper — ENS Intelligence Layer. Nothing to install.
cancel_offer 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 cancel_offer 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 cancel_offer. 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.
cancel_offer is provided by the Name Whisper — ENS Intelligence Layer MCP server (https://namewhisper.ai/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 42 Name Whisper — ENS Intelligence Layer tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
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