diff --git a/src/rpc/server.h b/src/rpc/server.h
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -225,8 +225,7 @@
     /**
      * Appends a CRPCCommand to the dispatch table.
      *
-     * Returns false if RPC server is already running (dump concurrency
-     * protection).
+     * Precondition: RPC server is not running
      *
      * Commands with different method names but the same unique_id will
      * be considered aliases, and only the first registered method name will
@@ -235,7 +234,7 @@
      * between calls based on method name, and aliased commands can also
      * register different names, types, and numbers of parameters.
      */
-    bool appendCommand(const std::string &name, const CRPCCommand *pcmd);
+    void appendCommand(const std::string &name, const CRPCCommand *pcmd);
     bool removeCommand(const std::string &name, const CRPCCommand *pcmd);
 };
 
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -315,14 +315,12 @@
     }
 }
 
-bool CRPCTable::appendCommand(const std::string &name,
+void CRPCTable::appendCommand(const std::string &name,
                               const CRPCCommand *pcmd) {
-    if (IsRPCRunning()) {
-        return false;
-    }
+    // Only add commands before rpc is running
+    CHECK_NONFATAL(!IsRPCRunning());
 
     mapCommands[name].push_back(pcmd);
-    return true;
 }
 
 bool CRPCTable::removeCommand(const std::string &name,