> [!NOTE]
> **Note:** If you are new to the Google Ads API, we recommend reading the [Getting
> Started](https://developers.google.com/google-ads/api/docs/get-started/make-first-call) guide first, which covers how to set up your account and make your first API call. Make sure to follow the *curl* tab.

While `Mutate`, `Search`, and `SearchStream` are the most common methods
in the Google Ads API, there are many others for specific purposes. All services and
their APIs are documented in the
[reference documentation](https://developers.google.com/google-ads/api/reference/rpc/v26/overview).

## Protocol buffer RPC to REST mappings

All the service endpoints (whether using REST and gRPC) are ultimately defined
in the
[.proto files of the services package](https://github.com/googleapis/googleapis/tree/HEAD/google/ads/googleads/v26/services)
using the
[proto3 Interface Definition Language](https://cloud.google.com/apis/design/proto3).

### Example: ListAccessibleCustomers

For example, the [`customer_service.proto`](https://github.com/googleapis/googleapis/tree/HEAD/google/ads/googleads/v26/services/customer_service.proto) file
defines a `ListAccessibleCustomers` method, in addition to the standard `Mutate`
. Its [`google.api.http`](https://google.aip.dev/127) annotation describes
how the method maps to HTTP. It uses an HTTP `GET` with the custom verb
`listAccessibleCustomers`:

```
rpc ListAccessibleCustomers(ListAccessibleCustomersRequest)
    returns (ListAccessibleCustomersResponse) {
  option (google.api.http) = {
    get: "/v26/customers:listAccessibleCustomers"
  };
}
```

This maps to the
[customers.listAccessibleCustomers](https://developers.google.com/google-ads/api/reference/rpc/v26/CustomerService/ListAccessibleCustomers)
REST method.

### Example: CreateCustomerClient

Another example from [`customer_service.proto`](https://github.com/googleapis/googleapis/tree/HEAD/google/ads/googleads/v26/services/customer_service.proto) is
the `CreateCustomerClient` method. Its `google.api.http` annotation describes an
HTTP `POST` using the custom verb `createCustomerClient`:

```
rpc CreateCustomerClient(CreateCustomerClientRequest)
    returns (CreateCustomerClientResponse) {
  option (google.api.http) = {
    post: "/v26/customers/{customer_id=*}:createCustomerClient"
    body: "*"
  };
  option (google.api.method_signature) = "customer_id,customer_client";
}
```

This maps to the [customers.createCustomerClient](https://developers.google.com/google-ads/api/reference/rpc/v26/CustomerService/CreateCustomerClient)
REST method.