diff --git a/examples/http_client.cc b/examples/http_client.cc
index 9f4d55d..52dd807 100644
--- a/examples/http_client.cc
+++ b/examples/http_client.cc
@@ -5,8 +5,6 @@
 
 using namespace webcc;
 
-// -----------------------------------------------------------------------------
-
 #if (defined(WIN32) || defined(_WIN64))
 // You need to set environment variable SSL_CERT_FILE properly to enable
 // SSL verification.
@@ -15,9 +13,6 @@ bool kSslVerify = false;
 bool kSslVerify = true;
 #endif
 
-// -----------------------------------------------------------------------------
-// Examples
-
 void ExampleBasic() {
   webcc::HttpClientSession session;
 
diff --git a/webcc/http_client_session.cc b/webcc/http_client_session.cc
index c81ba9e..bf5ecc3 100644
--- a/webcc/http_client_session.cc
+++ b/webcc/http_client_session.cc
@@ -37,9 +37,9 @@ static void SetHeaders(const std::vector<std::string>& headers,
   }
 }
 
-HttpResponsePtr HttpClientSession::Get(const std::string& url,
-                                       const std::vector<std::string>& parameters,
-                                       const std::vector<std::string>& headers) {
+HttpResponsePtr HttpClientSession::Get(
+    const std::string& url, const std::vector<std::string>& parameters,
+    const std::vector<std::string>& headers) {
   HttpRequestBuilder builder{http::methods::kGet};
   builder.url(url);
 
@@ -53,9 +53,9 @@ HttpResponsePtr HttpClientSession::Get(const std::string& url,
   return Request(builder());
 }
 
-HttpResponsePtr HttpClientSession::Post(const std::string& url,
-                                        std::string&& data, bool json,
-                                        const std::vector<std::string>& headers) {
+HttpResponsePtr HttpClientSession::Post(
+    const std::string& url, std::string&& data, bool json,
+    const std::vector<std::string>& headers) {
   HttpRequestBuilder builder{http::methods::kPost};
   builder.url(url);
 
@@ -67,9 +67,9 @@ HttpResponsePtr HttpClientSession::Post(const std::string& url,
   return Request(builder());
 }
 
-HttpResponsePtr HttpClientSession::Put(const std::string& url,
-                                       std::string&& data, bool json,
-                                       const std::vector<std::string>& headers) {
+HttpResponsePtr HttpClientSession::Put(
+    const std::string& url, std::string&& data, bool json,
+    const std::vector<std::string>& headers) {
   HttpRequestBuilder builder{http::methods::kPut};
   builder.url(url);
 
@@ -81,8 +81,8 @@ HttpResponsePtr HttpClientSession::Put(const std::string& url,
   return Request(builder());
 }
 
-HttpResponsePtr HttpClientSession::Delete(const std::string& url,
-                                          const std::vector<std::string>& headers) {
+HttpResponsePtr HttpClientSession::Delete(
+    const std::string& url, const std::vector<std::string>& headers) {
   HttpRequestBuilder builder{http::methods::kDelete};
   builder.url(url);
 
@@ -91,9 +91,9 @@ HttpResponsePtr HttpClientSession::Delete(const std::string& url,
   return Request(builder());
 }
 
-HttpResponsePtr HttpClientSession::Patch(const std::string& url,
-                                         std::string&& data, bool json,
-                                         const std::vector<std::string>& headers) {
+HttpResponsePtr HttpClientSession::Patch(
+    const std::string& url, std::string&& data, bool json,
+    const std::vector<std::string>& headers) {
   HttpRequestBuilder builder{http::methods::kPatch};
   builder.url(url);
 
@@ -130,7 +130,7 @@ void HttpClientSession::InitHeaders() {
   // probably have called the second one "zlib" instead to avoid confusion with
   // the raw deflate compressed data format.
   // Simply put, "deflate" is not recommended for HTTP 1.1 encoding.
-  //
+
   headers_.Set(kAcceptEncoding, "gzip, deflate");
 
   headers_.Set(kAccept, "*/*");
@@ -145,7 +145,7 @@ HttpResponsePtr HttpClientSession::Send(HttpRequestPtr request) {
 
   const HttpClientPool::Key key{request->url()};
 
-  // Reuse a connection or not.
+  // Reuse a pooled connection.
   bool reuse = false;
 
   HttpClientPtr client = pool_.Get(key);
diff --git a/webcc/http_client_session.h b/webcc/http_client_session.h
index 4cad2c0..5180146 100644
--- a/webcc/http_client_session.h
+++ b/webcc/http_client_session.h
@@ -13,6 +13,10 @@
 
 namespace webcc {
 
+// HTTP requests session providing connection-pooling, configuration and more.
+// NOTE:
+// A session shouldn't be shared by multiple threads. Please create a new
+// session for each thread instead.
 class HttpClientSession {
 public:
   HttpClientSession();