diff --git a/include/openthread/commissioner.h b/include/openthread/commissioner.h
index facbae7d9..ca2d54a89 100644
--- a/include/openthread/commissioner.h
+++ b/include/openthread/commissioner.h
@@ -96,7 +96,7 @@ OTAPI otError OTCALL otCommissionerStop(otInstance *aInstance);
  * @retval OT_ERROR_INVALID_ARGS  @p aExtAddress or @p aPSKd is invalid.
  * @retval OT_ERROR_INVALID_STATE The commissioner is not active.
  *
- * @note Only use this after successfully started the Commissioner role by otCommissionerStart().
+ * @note Only use this after successfully starting the Commissioner role with otCommissionerStart().
  *
  */
 OTAPI otError OTCALL otCommissionerAddJoiner(otInstance *aInstance, const otExtAddress *aExtAddress,
@@ -113,7 +113,7 @@ OTAPI otError OTCALL otCommissionerAddJoiner(otInstance *aInstance, const otExtA
  * @retval OT_ERROR_INVALID_ARGS  @p aExtAddress is invalid.
  * @retval OT_ERROR_INVALID_STATE The commissioner is not active.
  *
- * @note Only use this after successfully started the Commissioner role by otCommissionerStart().
+ * @note Only use this after successfully starting the Commissioner role with otCommissionerStart().
  *
  */
 OTAPI otError OTCALL otCommissionerRemoveJoiner(otInstance *aInstance, const otExtAddress *aExtAddress);
@@ -143,7 +143,7 @@ OTAPI otError OTCALL otCommissionerSetProvisioningUrl(otInstance *aInstance, con
  * @retval OT_ERROR_NO_BUFS       Insufficient buffers to generate an Announce Begin message.
  * @retval OT_ERROR_INVALID_STATE The commissioner is not active.
  *
- * @note Only use this after successfully started the Commissioner role by otCommissionerStart().
+ * @note Only use this after successfully starting the Commissioner role with otCommissionerStart().
  *
  */
 OTAPI otError OTCALL otCommissionerAnnounceBegin(otInstance *aInstance, uint32_t aChannelMask, uint8_t aCount,
@@ -178,7 +178,7 @@ typedef void (OTCALL *otCommissionerEnergyReportCallback)(uint32_t aChannelMask,
  * @retval OT_ERROR_NO_BUFS       Insufficient buffers to generate an Energy Scan Query message.
  * @retval OT_ERROR_INVALID_STATE The commissioner is not active.
  *
- * @note Only use this after successfully started the Commissioner role by otCommissionerStart().
+ * @note Only use this after successfully starting the Commissioner role with otCommissionerStart().
  *
  */
 OTAPI otError OTCALL otCommissionerEnergyScan(otInstance *aInstance, uint32_t aChannelMask, uint8_t aCount,
@@ -209,7 +209,7 @@ typedef void (OTCALL *otCommissionerPanIdConflictCallback)(uint16_t aPanId, uint
  * @retval OT_ERROR_NO_BUFS       Insufficient buffers to generate a PAN ID Query message.
  * @retval OT_ERROR_INVALID_STATE The commissioner is not active.
  *
- * @note Only use this after successfully started the Commissioner role by otCommissionerStart().
+ * @note Only use this after successfully starting the Commissioner role with otCommissionerStart().
  *
  */
 OTAPI otError OTCALL otCommissionerPanIdQuery(otInstance *aInstance, uint16_t aPanId, uint32_t aChannelMask,
diff --git a/include/openthread/openthread.h b/include/openthread/openthread.h
index 920a0ba52..84c097d29 100644
--- a/include/openthread/openthread.h
+++ b/include/openthread/openthread.h
@@ -102,6 +102,7 @@ extern "C" {
  * @defgroup api-joiner         Joiner
  * @defgroup api-thread-router  Router/Leader
  * @brief This module includes functions for Thread Routers and Leaders.
+ * @defgroup api-server         Server
  * @defgroup api-tmf-proxy      TMF Proxy
  *
  * @}
diff --git a/include/openthread/server.h b/include/openthread/server.h
index 50a4a9343..1d3a9a6d3 100644
--- a/include/openthread/server.h
+++ b/include/openthread/server.h
@@ -115,7 +115,7 @@ OTAPI otError OTCALL otServerGetNextService(otInstance *aInstance, otNetworkData
  *
  * @param[in]  aInstance A pointer to an OpenThread instance.
  *
- * retval OT_ERROR_NONE  Successfully queued a Server Data Request message for delivery.
+ * @retval OT_ERROR_NONE  Successfully queued a Server Data Request message for delivery.
  *
  * @sa otServerAddService
  * @sa otServerRemoveService