Comments API: replies, user search, and webhook enrichment

Three additions to the Comments API that enable integrations to participate in comment threads and build richer comment notifications.

New endpoint: Create comment reply

The Create Comment Reply endpoint lets you post a reply to an existing comment thread programmatically.

Method: POST /beta/sites/{site_id}/comments/{comment_thread_id}/replies
Scope: comments:write
Author attribution: The reply is always attributed to the user who authorized the OAuth token.
Mentions: To @mention a user in a reply, include their user ID in double square brackets in the content, field such as [[userId]]. Use the new Search Users by Email endpoint to look up user IDs.

Creating a reply automatically fires the comment_created webhook.

New endpoint: Search users by email

The Search Users by Email endpoint lets you look up a workspace user by their exact email address, returning their Webflow user ID for use in comment @mentions.

Method: GET /beta/sites/{site_id}/comments/users?email={email}
Scope: comments:read
Search type: Exact email match only — no partial or fuzzy search.
Returns an empty array if no user with the specified email address is found.

Webhook enrichment: comment location data

The comment_created webhook payload now includes three new fields that identify where a comment is anchored on a page.

Field	Type	Description
`objectId`	`string`	The ID of the page or CMS collection item the comment is on
`objectType`	`page` \| `cms-item`	Whether the comment is on a page or a CMS item
`elementId`	`string`	The ID of the DOM element the comment pin is attached to

The existing pageId field is unchanged; it always contains the containing page ID. For comments on CMS items, objectId is the item ID, while pageId is the template page.

These fields are additive. Existing webhook consumers are not affected.