diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 18b37a9..7a28a19 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -419,11 +419,22 @@
 }
 mbedtls_ecp_keypair;
 
-/*
- * Point formats, from RFC 4492's enum ECPointFormat
+/**
+ * The uncompressed point format for Short Weierstrass curves
+ * (MBEDTLS_ECP_DP_SECP_XXX and MBEDTLS_ECP_DP_BP_XXX).
  */
-#define MBEDTLS_ECP_PF_UNCOMPRESSED    0   /**< Uncompressed point format. */
-#define MBEDTLS_ECP_PF_COMPRESSED      1   /**< Compressed point format. */
+#define MBEDTLS_ECP_PF_UNCOMPRESSED    0
+/**
+ * The compressed point format for Short Weierstrass curves
+ * (MBEDTLS_ECP_DP_SECP_XXX and MBEDTLS_ECP_DP_BP_XXX).
+ *
+ * \warning     While this format is supported for all concerned curves for
+ *              writing, when it comes to parsing, it is not supported for all
+ *              curves. Specifically, parsing compressed points on
+ *              MBEDTLS_ECP_DP_SECP224R1 and MBEDTLS_ECP_DP_SECP224K1 is not
+ *              supported.
+ */
+#define MBEDTLS_ECP_PF_COMPRESSED      1
 
 /*
  * Some other constants from RFC 4492
@@ -752,6 +763,9 @@
  *                  belongs to the given group, see mbedtls_ecp_check_pubkey()
  *                  for that.
  *
+ * \note            For compressed points, see #MBEDTLS_ECP_PF_COMPRESSED for
+ *                  limitations.
+ *
  * \param grp       The group to which the point should belong.
  *                  This must be initialized and have group parameters
  *                  set, for example through mbedtls_ecp_group_load().
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 0392bd4..e66a9f8 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -804,6 +804,9 @@
  *                  with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
  *                  specific key type, check the result with mbedtls_pk_can_do().
  *
+ * \note            For compressed points, see #MBEDTLS_ECP_PF_COMPRESSED for
+ *                  limitations.
+ *
  * \note            The key is also checked for correctness.
  *
  * \return          0 if successful, or a specific PK or PEM error code