> ## Documentation Index > Fetch the complete documentation index at: https://docs.signalmd.dev/llms.txt > Use this file to discover all available pages before exploring further. # Signals > Small observations about moments in a call, shown on the call page. They help explain an issue and are never an issue on their own. A signal is a small observation about one moment in a call, such as the agent saying a vehicle was added when nothing in the call added it. Signals appear in the **Signals** section of the call page. A signal is evidence. It is never an issue by itself. ## Signals and issues | | Signal | Issue | | - | - | - | | About | One moment in one call | A problem across calls | | Where you see it | The **Signals** section of a call page | **Issues** | | Ranked | No | Yes | Not every moment a signal notes needs fixing. Issues are the problems that cost your callers or your business something across calls, and signals help you see what happened on each call behind them. ## What a signal looks like Each signal has a short label that says what was noticed, such as **Said it was done, no tool behind it** when the agent claimed an action ("OK, I've added that vehicle") that nothing in the call performed. Hover a signal to see what was found, followed by how it is known: * **Confirmed in code.** The call record shows it directly. * **Judged by a model.** It is a reading of the conversation. Weigh it as a lead and check the moment yourself. ## How to use signals * **Play the moment.** Click a signal to play the call from that point. * **Follow it to the issue.** An arrow beside a signal opens the issue it feeds, when there is one. * **Read them in groups.** Signals with the same label are grouped with a count, so a moment that happened several times on one call shows once. * **Check a cause.** When an issue's cause points at a step or a tool, the signals on its calls show what happened there, call by call. Calls where the caller never spoke have no signals, because there was no conversation to check. SignalMD does not check every moment of every call, so a call with no signals is not proof that nothing went wrong. ## Next steps How problems across calls become one issue to fix. The call page where signals appear. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.