diff --git a/docs/configuration/https.md b/docs/configuration/https.md
index b1e078cdd..1799739d0 100644
--- a/docs/configuration/https.md
+++ b/docs/configuration/https.md
@@ -36,6 +36,9 @@ tls_server_config:
   # Server policy for client authentication. Maps to ClientAuth Policies.
   # For more detail on clientAuth options:
   # https://golang.org/pkg/crypto/tls/#ClientAuthType
+  #
+  # NOTE: If you want to enable client authentication, you need to use
+  # RequireAndVerifyClientCert. Other values are insecure.
   [ client_auth_type: <string> | default = "NoClientCert" ]
 
   # CA certificate for client certificate authentication to the server.
diff --git a/go.mod b/go.mod
index 498cc4872..4e482af36 100644
--- a/go.mod
+++ b/go.mod
@@ -48,7 +48,7 @@ require (
 	github.com/prometheus/client_golang v1.11.0
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.29.0
-	github.com/prometheus/exporter-toolkit v0.6.0
+	github.com/prometheus/exporter-toolkit v0.6.1
 	github.com/scaleway/scaleway-sdk-go v1.0.0-beta.7.0.20210223165440-c65ae3540d44
 	github.com/shurcooL/httpfs v0.0.0-20190707220628-8d4bc4ba7749
 	github.com/shurcooL/vfsgen v0.0.0-20200824052919-0d455de96546
diff --git a/go.sum b/go.sum
index dc7d0db2a..102b2b711 100644
--- a/go.sum
+++ b/go.sum
@@ -1094,8 +1094,8 @@ github.com/prometheus/common v0.26.0/go.mod h1:M7rCNAaPfAosfx8veZJCuw84e35h3Cfd9
 github.com/prometheus/common v0.29.0 h1:3jqPBvKT4OHAbje2Ql7KeaaSicDBCxMYwEJU1zRJceE=
 github.com/prometheus/common v0.29.0/go.mod h1:vu+V0TpY+O6vW9J44gczi3Ap/oXXR10b+M/gUGO4Hls=
 github.com/prometheus/exporter-toolkit v0.5.1/go.mod h1:OCkM4805mmisBhLmVFw858QYi3v0wKdY6/UxrT0pZVg=
-github.com/prometheus/exporter-toolkit v0.6.0 h1:rGoS9gIqj3sXaw+frvo0ozCs1CxBRqpOCGsbixC52UI=
-github.com/prometheus/exporter-toolkit v0.6.0/go.mod h1:ZUBIj498ePooX9t/2xtDjeQYwvRpiPP2lh5u4iblj2g=
+github.com/prometheus/exporter-toolkit v0.6.1 h1:Aqk75wQD92N9CqmTlZwjKwq6272nOGrWIbc8Z7+xQO0=
+github.com/prometheus/exporter-toolkit v0.6.1/go.mod h1:ZUBIj498ePooX9t/2xtDjeQYwvRpiPP2lh5u4iblj2g=
 github.com/prometheus/procfs v0.0.0-20180125133057-cb4147076ac7/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20190117184657-bf6a532e95b1/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=