Refreshed circuits model documentation

docs/models/circuits/provider.md

@@ -1,5 +1,40 @@
 # Providers
 
-A circuit provider is any entity which provides some form of connectivity of among sites or organizations within a site. While this obviously includes carriers which offer Internet and private transit service, it might also include Internet exchange (IX) points and even organizations with whom you peer directly. Each circuit within NetBox must be assigned a provider and a circuit ID which is unique to that provider.
+A provider is any entity which provides some form of connectivity of among sites or organizations within a site. While this obviously includes carriers which offer Internet and private transit service, it might also include Internet exchange (IX) points and even organizations with whom you peer directly. Each [circuit](./circuit.md) within NetBox must be assigned a provider and a circuit ID which is unique to that provider.
 
-Each provider may be assigned an autonomous system number (ASN), an account number, and contact information.
+## Fields
+
+### Name
+
+A unique human-friendly name.
+
+### Slug
+
+A unique URL-friendly identifier. (This value can be used for filtering.)
+
+### ASN
+
+The AS number assigned to this provider.
+
+!!! warning "Legacy field"
+    This field is being removed in NetBox v3.4. Users are highly encouraged to use the [ASN model](../ipam/asn.md) to track AS number assignment for providers.
+
+### ASNs
+
+The [AS numbers](../ipam/asn.md) assigned to this provider (optional).
+
+### Account Number
+
+The administrative account identifier tied to this provider for your organization.
+
+### Portal URL
+
+The URL for the provider's customer service portal.
+
+### NOC Contact
+
+Contact details for the provider's network operations center (NOC).
+
+### Admin Contact
+
+Administrative contact details for the provider.