substack

Substack Integration for Autohive

Integration with Substack for searching publications, reading posts and comments. No authentication required — all actions use Substack's public APIs.

Overview

This integration provides read-only access to public Substack content. It allows you to:

• Browse and paginate a publication's post archive
• Fetch full post content including body HTML
• Search for publications across the entire Substack platform
• Search posts within a specific publication by keyword
• Retrieve comments on any post

Note: Substack has no official public API. This integration uses internal endpoints that are widely used but undocumented and subject to change.

Authentication

No authentication required. All 5 actions work without credentials.

Actions

get_publication_posts

List posts from a Substack publication's archive. Supports sorting, keyword filtering, and pagination.

Inputs:

Field	Type	Required	Description
publication_url	string	Yes	Base URL of the publication, e.g. https://example.substack.com or a custom domain
sort	string	No	Sort order: new (default) or top
search	string	No	Optional keyword filter
offset	integer	No	Number of posts to skip for pagination (default: 0)
limit	integer	No	Maximum posts to return, 1–50 (default: 12)

Example:

{
  "publication_url": "https://on.substack.com",
  "sort": "top",
  "limit": 5
}

Output:

{
  "posts": [
    {
      "id": 12345678,
      "slug": "my-post-title",
      "title": "My Post Title",
      "subtitle": "A subtitle",
      "post_date": "2024-01-01T00:00:00.000Z",
      "canonical_url": "https://example.substack.com/p/my-post-title",
      "audience": "everyone",
      "paywall": false,
      "reading_time_minutes": 5,
      "like_count": 42,
      "comment_count": 8,
      "type": "newsletter"
    }
  ],
  "count": 1
}

---

get_post

Fetch the full content of a specific post by its slug. Returns body HTML. Paywalled posts return truncated content for non-subscribers.

Inputs:

Field	Type	Required	Description
publication_url	string	Yes	Base URL of the publication
slug	string	Yes	Post slug from the URL (e.g. my-post-title from .../p/my-post-title)

Example:

{
  "publication_url": "https://on.substack.com",
  "slug": "introducing-the-substack-recording"
}

Output:

{
  "id": 190636964,
  "slug": "introducing-the-substack-recording",
  "title": "Introducing the Substack Recording Studio",
  "subtitle": "Pre-record your show, plus new tools for going live",
  "body_html": "<p>Full post content here...</p>",
  "post_date": "2026-03-12T17:01:34.272Z",
  "canonical_url": "https://on.substack.com/p/introducing-the-substack-recording",
  "audience": "everyone",
  "paywall": false,
  "reading_time_minutes": 3,
  "like_count": 120,
  "comment_count": 15,
  "type": "newsletter"
}

---

search_publications

Search for Substack publications by keyword across the entire platform.

Inputs:

Field	Type	Required	Description
query	string	Yes	Search query
page	integer	No	0-based page number (default: 0)
limit	integer	No	Results per page, 1–100 (default: 10)

Example:

{
  "query": "technology startups",
  "limit": 5
}

Output:

{
  "publications": [
    {
      "id": 1234,
      "name": "Tech Newsletter",
      "subdomain": "technewsletter",
      "description": "Weekly tech insights",
      "subscriber_count": 15000,
      "logo_url": "https://..."
    }
  ],
  "more": true
}

---

search_posts

Search posts within a specific Substack publication by keyword.

Inputs:

Field	Type	Required	Description
publication_url	string	Yes	Base URL of the publication
query	string	Yes	Search query
offset	integer	No	Pagination offset (default: 0)
limit	integer	No	Maximum results, 1–50 (default: 10)

Example:

{
  "publication_url": "https://on.substack.com",
  "query": "writers",
  "limit": 5
}

Output:

{
  "posts": [
    {
      "id": 99887766,
      "slug": "matching-post",
      "title": "Matching Post",
      "post_date": "2024-06-01T00:00:00.000Z",
      "canonical_url": "https://on.substack.com/p/matching-post",
      "audience": "everyone",
      "paywall": false,
      "like_count": 30,
      "comment_count": 4,
      "type": "newsletter"
    }
  ],
  "count": 1
}

---

get_post_comments

Fetch comments for a specific post. Requires the numeric post id (not the slug).

Inputs:

Field	Type	Required	Description
publication_url	string	Yes	Base URL of the publication
post_id	integer	Yes	Numeric post ID — the id field from get_publication_posts or get_post
sort	string	No	Sort order: best (default) or newest
all_comments	boolean	No	Return all comments (default: true)

Example:

{
  "publication_url": "https://on.substack.com",
  "post_id": 190636964,
  "sort": "newest"
}

Output:

{
  "comments": [
    {
      "id": 55443322,
      "body": "Great post!",
      "date": "2024-01-02T00:00:00.000Z",
      "author_name": "Alice",
      "author_id": 99,
      "like_count": 3,
      "children": []
    }
  ],
  "count": 1
}

---

Notes

• publication_url accepts both https://example.substack.com and bare hostnames like example.substack.com
• Custom domains (e.g. https://newsletter.example.com) are supported
• get_post_comments requires the numeric post_id, not the slug — get it from get_publication_posts or get_post
• Paywalled post body_html is truncated for non-subscribers
• Substack's undocumented APIs may change without notice