diff --git a/client/client.go b/client/client.go
index 529ce2d..6e19217 100644
--- a/client/client.go
+++ b/client/client.go
@@ -19,24 +19,15 @@ import (
 
 type Client struct {
 	http.Client
-	URL      string
-	PubKey   []byte
-	Sign     SignFunc
-	Validate ValidateFunc
-	Log      slog.Logger
+	URL    string
+	PubKey []byte
+	// Sign is a function which must be provided to an instance of Client so
+	// that it can sign request bodies using the PrivKey of the specified
+	// address.
+	Sign func(context.Context, string, stdaddr.Address) ([]byte, error)
+	Log  slog.Logger
 }
 
-// SignFunc is the signature of a function must be provided to an instance of
-// Client so that it can sign request bodies using the PrivKey of the specified
-// address.
-type SignFunc func(context.Context, string, stdaddr.Address) ([]byte, error)
-
-// ValidateFunc is the signature of a function which must be provided to an
-// instance of Client so that it can validate that HTTP responses are signed
-// with the provided pubkey. This package provides a default implementation of
-// ValidateFunc named ValidateServerResponse.
-type ValidateFunc func(resp *http.Response, body []byte, serverPubkey []byte) error
-
 func (c *Client) VspInfo(ctx context.Context) (*types.VspInfoResponse, error) {
 	var resp *types.VspInfoResponse
 	err := c.get(ctx, "/api/v3/vspinfo", &resp)
@@ -223,7 +214,7 @@ func (c *Client) do(ctx context.Context, method, path string, addr stdaddr.Addre
 			status, http.StatusText(status), respBody)
 	}
 
-	err = c.Validate(reply, respBody, c.PubKey)
+	err = ValidateServerSignature(reply, respBody, c.PubKey)
 	if err != nil {
 		return fmt.Errorf("authenticate server response: %v", err)
 	}
diff --git a/client/client_test.go b/client/client_test.go
index 8543caa..2f1f809 100644
--- a/client/client_test.go
+++ b/client/client_test.go
@@ -7,19 +7,10 @@ import (
 	"net/http/httptest"
 	"testing"
 
-	"github.com/decred/dcrd/txscript/v4/stdaddr"
 	"github.com/decred/slog"
 	"github.com/decred/vspd/types"
 )
 
-func NoopSign(ctx context.Context, message string, address stdaddr.Address) ([]byte, error) {
-	return nil, nil
-}
-
-func NoopValidate(resp *http.Response, body []byte, serverPubkey []byte) error {
-	return nil
-}
-
 // TestErrorDetails ensures errors returned by client.do contain adequate
 // information for debugging (HTTP status and response body).
 func TestErrorDetails(t *testing.T) {
@@ -68,11 +59,9 @@ func TestErrorDetails(t *testing.T) {
 			}))
 
 			client := Client{
-				URL:      testServer.URL,
-				PubKey:   []byte("fake pubkey"),
-				Sign:     NoopSign,
-				Validate: NoopValidate,
-				Log:      slog.Disabled,
+				URL:    testServer.URL,
+				PubKey: []byte("fake pubkey"),
+				Log:    slog.Disabled,
 			}
 
 			var resp interface{}