> ## 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.

# Add Member

> Add a user to a group conversation

Adds a user to a group conversation. Only group conversations support explicit member management — this endpoint returns a 400 for direct and space conversations.

The caller must be an active `admin` of the conversation. The target user must belong to the same project.

If the user was previously a member who left or was removed, they are re-activated (their `isActive` is set back to `true` and `lastReadAt` is reset to now).

## Path Parameters

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

## Body Parameters

<ParamField body="userId" type="string" required>
  The ID of the user to add. Must belong to the same project.
</ParamField>

## Response

Returns the [ConversationMember](/data-models/conversation-member) record for the added user.

## Error Responses

<AccordionGroup>
  <Accordion title="Not Found — 404">
    ```json theme={null}
    { "error": "Conversation not found.", "code": "chat/not-found" }
    ```
  </Accordion>

  <Accordion title="Invalid Type — 400 Bad Request">
    ```json theme={null}
    { "error": "Members can only be added to group conversations.", "code": "chat/invalid-type" }
    ```
  </Accordion>

  <Accordion title="Forbidden — 403">
    ```json theme={null}
    { "error": "Only group admins can add members.", "code": "chat/not-a-member" }
    ```
  </Accordion>

  <Accordion title="Invalid Member — 400 Bad Request">
    ```json theme={null}
    { "error": "Target user does not belong to this project.", "code": "chat/invalid-member" }
    ```
  </Accordion>
</AccordionGroup>