perPage is the maximum number of results that may be returned per page.
For the API call you mention, I'd expect the result to be at most one of the structure below. The way the call is documented I can't see how it would return more than one. The list of clients is within the records[] element of the structure, which would not be paginated, i.e. the value of perPage makes no difference.
{
"clientId": "k74272e",
"mac": "22:33:44:55:66:77",
"manufacturer": "Apple",
"records": [
{
"network": {
"id": "N_24329156",
"organizationId": "2930418",
"name": "Main Office",
"timeZone": "America/Los_Angeles",
"tags": [ "tag1", "tag2" ],
"productTypes": [
"appliance",
"switch",
"wireless"
],
"enrollmentString": "my-enrollment-string",
"notes": "Additional description of the network",
"isBoundToConfigTemplate": false
},
"description": "Miles's phone",
"os": "iOS",
"user": "milesmeraki",
"ip": "1.2.3.4",
"ip6": "2001:db8:3c4d:15::1",
"firstSeen": 1518365681,
"lastSeen": 1526087474,
"vlan": "255",
"switchport": null,
"wirelessCapabilities": "802.11ac - 2.4 and 5 GHz",
"smInstalled": true,
"ssid": "My SSID",
"clientVpnConnections": [
{
"remoteIp": "1.2.3.4",
"connectedAt": 1522613355,
"disconnectedAt": 1522613360
}
],
"lldp": [
[
"System name",
"Some system name"
],
[
"System description",
"Some system description"
],
[ "Port ID", "1" ],
[
"Chassis ID",
"00:18:0a:00:00:00"
],
[
"Port description",
"eth0"
],
[
"System capabilities",
"Two-port MAC Relay"
]
],
"cdp": null,
"status": "Online"
}
]
}