> ## 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.

# Create Comment

> Create a new comment or reply on an entity

Creates a new comment on an entity, or a reply to an existing comment. The comment is attributed to the authenticated user. Notifications are sent to the entity owner, parent comment author (for replies), and mentioned users.

**Authentication required.**

## Body Parameters

<ParamField body="entityId" type="string" required>
  The UUID of the entity this comment belongs to.
</ParamField>

<ParamField body="content" type="string">
  The text content of the comment. At least one of `content`, `gif`, or `attachments` must be provided.
</ParamField>

<ParamField body="gif" type="object">
  A GIF to attach to the comment. At least one of `content`, `gif`, or `attachments` must be provided.

  ```json theme={null}
  {
    "id": "gif-id",
    "altText": "laughing cat",
    "gifUrl": "https://media.giphy.com/...",
    "gifPreviewUrl": "https://media.giphy.com/...",
    "url": "https://giphy.com/...",
    "aspectRatio": "16:9"
  }
  ```
</ParamField>

<ParamField body="attachments" type="object[]">
  An array of generic attachment objects. At least one of `content`, `gif`, or `attachments` must be provided.
</ParamField>

<ParamField body="parentId" type="string">
  The UUID of the parent comment. When provided, this comment is treated as a reply to that comment. The parent comment's author receives a reply notification.
</ParamField>

<ParamField body="referencedCommentId" type="string">
  The UUID of a comment being quoted or referenced. Used for quote-replies.
</ParamField>

<ParamField body="foreignId" type="string">
  Your application's identifier for this comment.
</ParamField>

<ParamField body="mentions" type="object[]">
  Users or spaces mentioned in the comment. Each mentioned user receives an in-app notification.

  * `{ type: "user", id: string, username: string, foreignId?: string }`
  * `{ type: "space", id: string, slug: string }`
</ParamField>

<ParamField body="metadata" type="object">
  A free-form JSON object for any custom data your application needs alongside the comment.
</ParamField>

<ParamField body="userId" type="string">
  Attribute the comment to a specific user. **Service or master key only.** Useful for backfilling comments from external systems.
</ParamField>

<ParamField body="createdAt" type="string">
  ISO 8601 datetime to backfill a creation timestamp. **Service or master key only.**
</ParamField>

<ParamField body="updatedAt" type="string">
  ISO 8601 datetime for `updatedAt`. Requires `createdAt`. Must be ≥ `createdAt`. **Service or master key only.**
</ParamField>

## Response

Returns `201 Created` with the new [Comment](/data-models/comment) object, populated with the author's user profile.

## Error Responses

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

  <Accordion title="Missing User — 400">
    ```json theme={null}
    { "error": "Missing user ID", "code": "comment/missing-user-id" }
    ```
  </Accordion>

  <Accordion title="No Content — 400">
    Returned when none of `content`, `gif`, or `attachments` is provided.
  </Accordion>
</AccordionGroup>