diff --git a/include/quiche.h b/include/quiche.h
index 0f63acb..6218877 100644
--- a/include/quiche.h
+++ b/include/quiche.h
@@ -58,10 +58,11 @@
     // There is no more work to do.
     QUICHE_ERR_DONE = -1,
 
-    // The provided buffer is too short.
+    // The provided buffer is too short. A quiche-specific internal error.
     QUICHE_ERR_BUFFER_TOO_SHORT = -2,
 
     // The provided packet cannot be parsed because its version is unknown.
+    // A quiche-specific internal error.
     QUICHE_ERR_UNKNOWN_VERSION = -3,
 
     // The provided packet cannot be parsed because it contains an invalid
@@ -72,7 +73,7 @@
     QUICHE_ERR_INVALID_PACKET = -5,
 
     // The operation cannot be completed because the connection is in an
-    // invalid state.
+    // invalid state. A quiche-specific internal error.
     QUICHE_ERR_INVALID_STATE = -6,
 
     // The operation cannot be completed because the stream is in an
@@ -82,10 +83,10 @@
     // The peer's transport params cannot be parsed.
     QUICHE_ERR_INVALID_TRANSPORT_PARAM = -8,
 
-    // A cryptographic operation failed.
+    // A cryptographic operation failed. A quiche-specific internal error.
     QUICHE_ERR_CRYPTO_FAIL = -9,
 
-    // The TLS handshake failed.
+    // The TLS handshake failed. A quiche-specific internal error.
     QUICHE_ERR_TLS_FAIL = -10,
 
     // The peer violated the local flow control limits.
@@ -100,7 +101,7 @@
     // The received data exceeds the stream's final size.
     QUICHE_ERR_FINAL_SIZE = -13,
 
-    // Error in congestion control.
+    // Error in congestion control. A quiche-specific internal error.
     QUICHE_ERR_CONGESTION_CONTROL = -14,
 };
 
@@ -411,7 +412,7 @@
     /// There is no error or no work to do
     QUICHE_H3_ERR_DONE = -1,
 
-    /// The provided buffer is too short.
+    /// The provided buffer is too short. A quiche-specific internal error.
     QUICHE_H3_ERR_BUFFER_TOO_SHORT = -2,
 
     /// Internal error in the HTTP/3 stack.
@@ -445,7 +446,7 @@
     /// QPACK Header block decompression failure.
     QUICHE_H3_ERR_QPACK_DECOMPRESSION_FAILED = -11,
 
-    /// Error originated from the transport layer.
+    /// Error originated from the transport layer. A quiche-specific internal error.
     QUICHE_H3_ERR_TRANSPORT_ERROR = -12,
 
     /// The underlying QUIC stream (or connection) doesn't have enough capacity
diff --git a/src/h3/mod.rs b/src/h3/mod.rs
index c6e456b..7936c5f 100644
--- a/src/h3/mod.rs
+++ b/src/h3/mod.rs
@@ -293,7 +293,7 @@
     /// There is no error or no work to do
     Done,
 
-    /// The provided buffer is too short.
+    /// The provided buffer is too short. A quiche-specific internal error.
     BufferTooShort,
 
     /// Internal error in the HTTP/3 stack.
@@ -327,11 +327,13 @@
     /// QPACK Header block decompression failure.
     QpackDecompressionFailed,
 
-    /// Error originated from the transport layer.
+    /// Error originated from the transport layer. A quiche-specific internal
+    /// error.
     TransportError(crate::Error),
 
     /// The underlying QUIC stream (or connection) doesn't have enough capacity
-    /// for the operation to complete. The application should retry later on.
+    /// for the operation to complete. The application should retry later on. A
+    /// quiche-specific internal error.
     StreamBlocked,
 
     /// Error in the payload of a SETTINGS frame.
diff --git a/src/lib.rs b/src/lib.rs
index 9f2cc90..9581ee1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -335,10 +335,11 @@
     /// There is no more work to do.
     Done,
 
-    /// The provided buffer is too short.
+    /// The provided buffer is too short. A quiche-specific internal error.
     BufferTooShort,
 
     /// The provided packet cannot be parsed because its version is unknown.
+    /// A quiche-specific internal error.
     UnknownVersion,
 
     /// The provided packet cannot be parsed because it contains an invalid
@@ -349,7 +350,7 @@
     InvalidPacket,
 
     /// The operation cannot be completed because the connection is in an
-    /// invalid state.
+    /// invalid state. A quiche-specific internal error.
     InvalidState,
 
     /// The operation cannot be completed because the stream is in an
@@ -359,10 +360,10 @@
     /// The peer's transport params cannot be parsed.
     InvalidTransportParam,
 
-    /// A cryptographic operation failed.
+    /// A cryptographic operation failed. A quiche-specific internal error.
     CryptoFail,
 
-    /// The TLS handshake failed.
+    /// The TLS handshake failed. A quiche-specific internal error.
     TlsFail,
 
     /// The peer violated the local flow control limits.
@@ -380,7 +381,7 @@
     /// The received data exceeds the stream's final size.
     FinalSize,
 
-    /// Error in congestion control.
+    /// Error in congestion control. A quiche-specific internal error.
     CongestionControl,
 }