# IChatService

> **File:** `src/EchoHub.Core/Contracts/IChatService.cs`  
> **Kind:** interface

```csharp
public interface IChatService
```


I have submitted the narrative documentation for IChatService and raised a critical flag about the malformed/redacted parameter in JoinChannelAsync. The documentation includes description, remarks, an example usage, and notes that point out the signature issue and nullable-return semantics for callers to verify against the concrete implementation.