diff --git a/NumLib/TimeStepping/Algorithms/EvolutionaryPIDcontroller.h b/NumLib/TimeStepping/Algorithms/EvolutionaryPIDcontroller.h
index 961fb6df51f085717194b4292e1903afca9864ff..9d18dfb6efcbf3e8bd61d659ed4ffc8902266360 100644
--- a/NumLib/TimeStepping/Algorithms/EvolutionaryPIDcontroller.h
+++ b/NumLib/TimeStepping/Algorithms/EvolutionaryPIDcontroller.h
@@ -91,7 +91,8 @@ public:
     /// Get a flag to indicate that this algorithm need to compute
     /// solution error.
     bool isSolutionErrorComputationNeeded() override { return true; }
-    /// Add specific times
+
+    /// \copydoc NumLib::TimeStepAlgorithm::addSpecifiedTimes
     void addSpecifiedTimes(
         std::vector<double> const& extra_specified_times) override;
 
diff --git a/NumLib/TimeStepping/Algorithms/TimeStepAlgorithm.h b/NumLib/TimeStepping/Algorithms/TimeStepAlgorithm.h
index 1ecfd586510aee4643cdd27a97b203991d008294..3dc899ab986ba0ebef7ca830291ea7681c2ebcba 100644
--- a/NumLib/TimeStepping/Algorithms/TimeStepAlgorithm.h
+++ b/NumLib/TimeStepping/Algorithms/TimeStepAlgorithm.h
@@ -86,7 +86,13 @@ public:
     /// solution error. The default return value is false.
     virtual bool isSolutionErrorComputationNeeded() { return false; }
 
-    /// Add specific times
+    /**
+     * Add specified times to the existing vector of the specified times.
+     * If there are specified times, they will be used as constraints in the
+     * computing of time step size such that the time step can exactly reach at
+     * the specified times. The function is mainly used to accept the specified
+     * times from the configuration of output.
+     */
     virtual void addSpecifiedTimes(std::vector<double> const& /*specified_times*/)
     {
     }