> ## Documentation Index
> Fetch the complete documentation index at: https://docs.replyke.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Mark as Read

> Advance the current user's read cursor to a given message

Updates the current user's `lastReadAt` timestamp on their conversation membership to the `createdAt` of the specified message. This reduces the unread count for the conversation.

The operation is monotonic — `lastReadAt` is never moved backward. If the provided message is older than the current `lastReadAt`, the call is a no-op.

## Path Parameters

<ParamField path="conversationId" type="string" required>
  The ID of the conversation.
</ParamField>

## Body Parameters

<ParamField body="messageId" type="string" required>
  The ID of the message to mark as read. The user's `lastReadAt` will be set to this message's `createdAt`.
</ParamField>

## Response

```json theme={null}
{ "message": "Marked as read." }
```

## Error Responses

<AccordionGroup>
  <Accordion title="Forbidden — 403">
    ```json theme={null}
    { "error": "You are not an active member of this conversation.", "code": "chat/not-a-member" }
    ```
  </Accordion>
</AccordionGroup>