Set a rule for a particular `visitor_id`, `browser_id`, `visitor_fingerprint`, `browser_fingerprint`, `hardware_fingerprint`, `network_fingerprint`, `cidr_block`, `asn`, or `country_code`. This is helpful in cases where you want to allow or block a specific user or fingerprint. You should be careful when setting rules for `browser_fingerprint`, `hardware_fingerprint`, or `network_fingerprint` as they can be shared across multiple users, and you could affect more users than intended. You may not set an `ALLOW` rule for a `country_code`. Rules are applied in the order specified above. For example, if an end user has an `ALLOW` rule set for their `visitor_id` but a `BLOCK` rule set for their `hardware_fingerprint`, they will receive an `ALLOW` verdict because the `visitor_id` rule takes precedence. If there are conflicts between multiple `cidr_block` rules (for example, if the `ip_address` of the end user overlaps with multiple CIDR blocks that have rules set), the conflicts are resolved as follows: - The smallest block size takes precedence. For example, if an `ip_address` overlaps with a `cidr_block` rule of `ALLOW` for a block with a prefix of `/32` and a `cidr_block` rule of `BLOCK` with a prefix of `/24`, the rule match verdict will be `ALLOW`. - Among equivalent size blocks, `BLOCK` takes precedence over `CHALLENGE`, which takes precedence over `ALLOW`. For example, if an `ip_address` overlaps with two `cidr_block` rules with blocks of the same size that return `CHALLENGE` and `ALLOW`, the rule match verdict will be `CHALLENGE`.