Approve or revoke an operator for ENS contract interactions. An approved operator can transfer ANY token owned by the approver on the specified contract. This is setApprovalForAll — it covers all tokens, not just one. Contracts: - **base_registrar** — ERC-721 tokens (unwrapped .eth names) - **n...
Part of the Name Whisper MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents use approve_operator to create or modify resources in Name Whisper. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call approve_operator repeatedly, creating or modifying resources faster than any human could review. Intercept's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Name Whisper.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
tools:
approve_operator:
rules:
- action: allow
rate_limit:
max: 30
window: 60See the full Name Whisper policy for all 34 tools.
Agents calling write-class tools like approve_operator have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Write risk category across the catalogue. The same policy patterns (rate-limit, validate) apply to each.
Approve or revoke an operator for ENS contract interactions. An approved operator can transfer ANY token owned by the approver on the specified contract. This is setApprovalForAll — it covers all tokens, not just one. Contracts: - **base_registrar** — ERC-721 tokens (unwrapped .eth names) - **name_wrapper** — ERC-1155 tokens (wrapped names and subnames) - **ens_registry** — ENS node ownership Common use cases: - Approve NameWrapper on BaseRegistrar before wrapping a name - Approve a marketplace contract for trading - Approve a management contract for batch operations - Revoke a previously approved operator Contract addresses: - BaseRegistrar: 0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85 - NameWrapper: 0xD4416b13d2b3a9aBae7AcD5D6C2BbDBE25686401 - ENS Registry: 0x00000000000C2E074eC69A0dFb2997BA6C7d2e1e WARNING: Only approve addresses you trust. An approved operator can move ALL your names on that contract.. It is categorised as a Write tool in the Name Whisper MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Add a rule in your Intercept YAML policy under the tools section for approve_operator. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Name Whisper MCP server.
approve_operator is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the approve_operator rule in your Intercept 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 Intercept policy for approve_operator. 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.
approve_operator is provided by the Name Whisper MCP server (namewhisper/ens-tools). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Open source. One binary. Zero dependencies.
npx -y @policylayer/intercept