diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 512fb6ca8..91cc5bddf 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -3076,31 +3076,65 @@
 
 /** \def MBEDTLS_SSL_MAX_CONTENT_LEN
  *
- * Maximum fragment length in bytes.
+ * Maximum length (in bytes) of incoming and outgoing plaintext fragments.
  *
- * Determines the size of both the incoming and outgoing TLS I/O buffers.
+ * This determines the size of both the incoming and outgoing TLS I/O buffers
+ * in such a way that both are capable of holding the specified amount of
+ * plaintext data, regardless of the protection mechanism used.
  *
- * Uncommenting MBEDTLS_SSL_IN_CONTENT_LEN and/or MBEDTLS_SSL_OUT_CONTENT_LEN
- * will override this length by setting maximum incoming and/or outgoing
- * fragment length, respectively.
+ * To configure incoming and outgoing I/O buffers separately, use
+ * #MBEDTLS_SSL_IN_CONTENT_LEN and #MBEDTLS_SSL_OUT_CONTENT_LEN,
+ * which overwrite the value set by this option.
+ *
+ * \note When using a value less than the default of 16KB on the client, it is
+ *       recommended to use the Maximum Fragment Length (MFL) extension to
+ *       inform the server about this limitation. On the server, there
+ *       is no supported, standardized way of informing the client about
+ *       restriction on the maximum size of incoming messages, and unless
+ *       the limitation has been communicated by other means, it is recommended
+ *       to only change the outgoing buffer size #MBEDTLS_SSL_OUT_CONTENT_LEN
+ *       while keeping the default value of 16KB for the incoming buffer.
+ *
+ * Uncomment to set the maximum plaintext size of both
+ * incoming and outgoing I/O buffers.
  */
 //#define MBEDTLS_SSL_MAX_CONTENT_LEN             16384
 
 /** \def MBEDTLS_SSL_IN_CONTENT_LEN
  *
- * Maximum incoming fragment length in bytes.
+ * Maximum length (in bytes) of incoming plaintext fragments.
  *
- * Uncomment to set the size of the inward TLS buffer independently of the
- * outward buffer.
+ * This determines the size of the incoming TLS I/O buffer in such a way
+ * that it is capable of holding the specified amount of plaintext data,
+ * regardless of the protection mechanism used.
+ *
+ * If this option is undefined, it inherits its value from
+ * #MBEDTLS_SSL_MAX_CONTENT_LEN.
+ *
+ * \note When using a value less than the default of 16KB on the client, it is
+ *       recommended to use the Maximum Fragment Length (MFL) extension to
+ *       inform the server about this limitation. On the server, there
+ *       is no supported, standardized way of informing the client about
+ *       restriction on the maximum size of incoming messages, and unless
+ *       the limitation has been communicated by other means, it is recommended
+ *       to only change the outgoing buffer size #MBEDTLS_SSL_OUT_CONTENT_LEN
+ *       while keeping the default value of 16KB for the incoming buffer.
+ *
+ * Uncomment to set the maximum plaintext size of the incoming I/O buffer
+ * independently of the outgoing I/O buffer.
  */
 //#define MBEDTLS_SSL_IN_CONTENT_LEN              16384
 
 /** \def MBEDTLS_SSL_OUT_CONTENT_LEN
  *
- * Maximum outgoing fragment length in bytes.
+ * Maximum length (in bytes) of outgoing plaintext fragments.
  *
- * Uncomment to set the size of the outward TLS buffer independently of the
- * inward buffer.
+ * This determines the size of the outgoing TLS I/O buffer in such a way
+ * that it is capable of holding the specified amount of plaintext data,
+ * regardless of the protection mechanism used.
+ *
+ * If this option undefined, it inherits its value from
+ * #MBEDTLS_SSL_MAX_CONTENT_LEN.
  *
  * It is possible to save RAM by setting a smaller outward buffer, while keeping
  * the default inward 16384 byte buffer to conform to the TLS specification.
@@ -3110,11 +3144,8 @@
  * The specific size requirement depends on the configured ciphers and any
  * certificate data which is sent during the handshake.
  *
- * For absolute minimum RAM usage, it's best to enable
- * MBEDTLS_SSL_MAX_FRAGMENT_LENGTH and reduce MBEDTLS_SSL_MAX_CONTENT_LEN. This
- * reduces both incoming and outgoing buffer sizes. However this is only
- * guaranteed if the other end of the connection also supports the TLS
- * max_fragment_len extension. Otherwise the connection may fail.
+ * Uncomment to set the maximum plaintext size of the outgoing I/O buffer
+ * independently of the incoming I/O buffer.
  */
 //#define MBEDTLS_SSL_OUT_CONTENT_LEN             16384