diff --git a/trusty/coverage/coverage.cpp b/trusty/coverage/coverage.cpp
index 5eccdc5..9613d0f 100644
--- a/trusty/coverage/coverage.cpp
+++ b/trusty/coverage/coverage.cpp
@@ -130,7 +130,7 @@
     req.open_args.uuid = uuid_;
     auto ret = Rpc(&req, -1, &resp);
     if (!ret.ok()) {
-        return Error() << "failed to open coverage client: ";
+        return Error() << "failed to open coverage client: " << ret.error();
     }
     record_len_ = resp.open_args.record_len;
     shm_len_ = RoundPageUp(record_len_);
@@ -153,7 +153,7 @@
     req.share_record_args.shm_len = shm_len_;
     ret = Rpc(&req, dma_buf, &resp);
     if (!ret.ok()) {
-        return Error() << "failed to send shared memory: ";
+        return Error() << "failed to send shared memory: " << ret.error();
     }
 
     shm_ = shm;
diff --git a/trusty/fuzz/utils.cpp b/trusty/fuzz/utils.cpp
index f4cf0b6..3526337 100644
--- a/trusty/fuzz/utils.cpp
+++ b/trusty/fuzz/utils.cpp
@@ -113,7 +113,7 @@
     int rc = write(ta_fd_, buf, len);
     alarm(0);
     if (rc < 0) {
-        return Error() << "failed to read TIPC message from TA: ";
+        return Error() << "failed to write TIPC message to TA: ";
     }
 
     return {};