Naming conventions

Enable the conventions

The conventions are opt-in. Enable them in the .editorconfig file of your solution:

[*.cs]
taggedvalues.infer_tags_from_names = true

Most ids then need no attribute:

public sealed class Customer
{
    public Guid Id { get; set; }        // a CustomerId, from the name of the type
    public Guid AccountId { get; set; } // an AccountId, from the name of the property
}

public sealed class CustomerService
{
    public void Delete(Guid customerId) { } // a CustomerId, from the name of the parameter

    public void Archive(Customer id) { }    // a CustomerId, from the type of the parameter

    public void M(Customer customer)
    {
        Delete(customer.Id);        // ok
        Delete(customer.AccountId); // MFTV0002
    }
}

The conventions

• A property or a field named Id takes the name of its declaring type: Id on Order is an "OrderId", and Id on the interface IEntity is an "EntityId". When the member is inherited, it is also an id of every type between the receiver and the declaring type. When it overrides or implements an Id, it is also an id of the base type or of the interface.
• A property, a field, or a parameter named xxxId takes its name: projectId is a "projectId", which is the same tag as "ProjectId", as tags are compared ignoring case. The s_, t_, and m_ prefixes and the leading underscores of fields are ignored: s_projectId and _projectId are both "projectId".
• A parameter named id takes the name of its type: void Load(Order id) is an "OrderId", and void Load(OrderId id) is an "OrderId" too. A parameter named id whose type is a primitive, a string, a Guid, an enum, or another type of the System namespace such as Int128 or DateTimeOffset is not tagged, as its type does not say what it identifies.

Limits

• Explicit tags always win over the conventions.
• Collections and indexers are not tagged by convention.
• The conventions only apply to the declarations of the project, not to the declarations of referenced projects or assemblies. Tag the members a referenced project exposes explicitly when its consumers must see the tags.

Rules specific to the conventions

• Two types with the same name in different namespaces give their Id the same tag, for instance Sales.Order.Id and Billing.Order.Id. The analyzer reports it (MFTV0006): add an explicit tag to at least one of them.
• A [ValueTag] attribute that declares the tag the convention already infers is redundant (MFTV0007): the code fix removes it.