AI agents call expand_cidr to retrieve information from TinyFn without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
| Parameter | Type | Required | Description |
|---|---|---|---|
limit | integer | — | Maximum IPs to return |
network | string | Yes | Network in CIDR notation |
Parameters from the server's own tool schema.
This tool retrieves and transforms existing data (a CIDR block notation) into a derived form (individual IP addresses). It is deterministic and read-only, performing network notation parsing similar to other utility tools on the server (validation, conversion, encoding). No data is created, modified, deleted, or external operations triggered.
From the tool's definition Tool name is 'expand_cidr' and description states it 'Expand[s] a CIDR to list of individual IPs' — a pure data transformation/query operation that reads and parses network notation into a list, with no side effects, modifications, or code execution.
Attacks that exploit this kind of access
Expand a CIDR to list of individual IPs. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.
expand_cidr accepts 2 parameters: limit, network. Required: network. The full parameter table on this page comes from the server's own tool schema.
Register the TinyFn MCP server in PolicyLayer and add a rule for expand_cidr: 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 TinyFn. Nothing to install.
expand_cidr 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 expand_cidr 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 expand_cidr. 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.
expand_cidr is provided by the TinyFn MCP server (https://api.tinyfn.io/mcp/all/). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
expand_cidr is one line of TinyFn's registry record.
The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.
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