Twilio provides several tools for investigating the interaction between your application and Twilio, including the Debugger, Alerts, and Request Inspector in our Project Console site. These tools allow developers can use to quickly see how well their application is performing. 

Error Logs

The Error Logs contain a detailed log of activity within your application. This log can help you dive deeper and and understand what Twilio resources were impacted and by whom. A detailed log, such as the one exposed via Events can be useful in understanding the root cause of a problem. 

Alarms

Alarms are flagged on specific Twilio requests that generate an error or warning. Calls and Messages with alarms are highlighted in red, making them easy to spot in your Call Logs and SMS Logs.

Clicking the timestamp of an alarmed call or message will give you a more details view of the alarm flagged.

Request Inspector

The Request Inspector lists all requests made between Twilio and your application for a call or SMS. To view the Request Inspector, just access your Call Logs or SMS Logs, and click a recent call or SMS timestamp. The Request Inspector details are found at the bottom of the details view.

Notice: For SMS, Message Request Inspector details are only available for 7 days. If the message is older than 7 days you will see this information box:

In addition, only the failed requests will be shown on Request Inspector. For success requests, the message "There were no HTTP Requests logged for this event." will be shown.

Notice: For Calls, Call Request Inspector details are only available for 30 days. If the call is older than 30 days you will see that no HTTP Requests were logged for the event:

For Calls you can also use the Request Replay feature to replay a request and see a side-by-side difference between the saved request and the new request.  The replayed request is identical to the original; Twilio will send all the same header and request information.