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+# NBErrorHandler API
+
+NoSQLBench provides a standard way of configuring error handling across
+driver implementations. This is provided by NBErrorHandler and associated
+classes.
+
+This error handler allows a chain of specific error handler behaviors to
+be invoked based on which type of error occurs. Additionally, the error
+handler is responsible for determining the cycle code to be used in
+advanced testing as well as for indicating whether or not an operation is
+eligible to be retried or not.
+
+The entire implementation is of this error handler is in package:
+
+    io.nosqlbench.engine.api.activityapi.errorhandling.modular
+
+The canonical example of using this API can be found in HttpAction.
+
+## NBErrorHandler Sketch
+
+As a feature that changes control-flow based on user input, it strongly
+suggests a specific type of flow within an action. The following
+pseudo-code explains this pattern.
+
+1. When an activity is initialized, also initialize an instance of
+   NBErrorHandler
+2. Each time an Action is called, loop while retries are not exhausted.
+    1. catch all exceptions and pass them to the error handler
+    2. Read the returned ErrorDetail.
+    3. If the error detail indicates that the error was retryable and
+       max_tries is not exhausted, retry the operation Otherwise, stop the
+       cycle.
+    4. In any case, when the cycle is complete, always return the cycle
+       code in the error detail, or 0 if no error was found
+