Substack Note Replies API
The reply branches under a note, each with its descendant comments.
GET /v1/substack/notes/{noteId}/replies1 credit Failed requests are free
About this endpoint
GET /v1/substack/notes/{noteId}/replies returns the reply branches for a note. data.root is the note the replies belong to, and data.replies[] holds branches of comment plus descendantComments[].
data.noteId names the note and data.moreBranches counts the reply branches not included in this response. lookupStatus is found or not_found. Each comment uses the note shape, so it carries body, author, engagement counts and attachments.
Substack Note Replies API FAQ
How is a reply branch shaped?
Each branch has a comment and a descendantComments array. The branch's first comment is the reply; the descendants are the replies under it.
What does moreBranches mean?
A response sometimes holds only some branches. moreBranches is the number left out, so you can tell a complete response from a partial one.
Does this include reactions on replies?
Yes. Each comment carries reactionCount, reactions, restackCount and replyCount when available.
How many credits does a replies lookup cost?
Pricing is documented on the operation in the API registry (shown on this page). Confirm on every response with meta.creditsCharged: that field is the billing source of truth.
Other Substack endpoints
- PublicationGET /v1/substack/publications/{publication}
- PostsGET /v1/substack/publications/{publication}/posts
- Post bodiesGET /v1/substack/publications/{publication}/posts/bodies
- Post indexGET /v1/substack/publications/{publication}/posts/index
- Search postsGET /v1/substack/publications/{publication}/posts/search
- RecommendationsGET /v1/substack/publications/{publication}/recommendations
- Publication feedGET /v1/substack/publications/{publication}/feed
- PostGET /v1/substack/posts/{post}