Background: Routine monitoring of depression symptoms and suicide risk is essential for appropriate treatment planning and risk management, but not well implemented by clinicians. We developed a brief online monitoring tool to address this issue. Aims: To investigate whether the online tool can feasibly improve monitoring; whether it is acceptable and useful for young people and their clinicians; and to determine whether a shorter tool could be implemented. Method: In a naturalistic longitudinal cohort study, 101 young people with depression completed the online tool on a tablet, prior to their consultation. Their results were immediately available to their clinician. Clients and clinicians answered questionnaires about acceptability and usefulness. Results: The tool was feasible to implement. Young people and clinicians found the tool acceptable and useful for understanding symptoms and risk. A brief three-item suicidal ideation screening measure correlated well with a validated measure of suicidal ideation. Conclusion: The online tool facilitates the quick exchange of key information about suicide risk, allowing clinicians to immediately address this. This level of responsiveness is likely to improve treatment outcomes. The brief version allows full integration into clinical practice to support clinicians managing those at risk of suicide.