> **For coding agents and LLMs:** This is one page from the Social Fetch docs (markdown export). For curated orientation and workflow guidance, start with [`/llms.txt`](https://www.socialfetch.dev/llms.txt); for agent onboarding and crawl rules, use [`/agents.txt`](https://www.socialfetch.dev/agents.txt); for the full endpoint list with links to pages like this one, use [`/llms-endpoints.txt`](https://www.socialfetch.dev/llms-endpoints.txt); for one platform's parameters and curls, use [`/llms-{platform}.txt`](https://www.socialfetch.dev/llms-tiktok.txt); use [`/llms.json`](https://www.socialfetch.dev/llms.json) when you need structured JSON for tool registration.

## This page

- **On-site (HTML):** <https://www.socialfetch.dev/docs/api/v1/substack/publications/publication/posts/get>
- **Markdown (.mdx) URL:** <https://www.socialfetch.dev/docs/api/v1/substack/publications/publication/posts/get.mdx>

## API base URL and authentication

- **API origin (from OpenAPI `servers`):** `https://api.socialfetch.dev`
- **Authentication:** send `x-api-key: sfk_...` on `/v1/**` and `/v2/**` routes unless the operation is explicitly anonymous (check OpenAPI `security`, the [API reference hub](https://www.socialfetch.dev/docs/api.mdx), [`/llms.txt`](https://www.socialfetch.dev/llms.txt), or [`/llms.json`](https://www.socialfetch.dev/llms.json) for each route).
- **OpenAPI JSON:** <https://www.socialfetch.dev/openapi.json>

## Recommended docs entrypoints (this site)

- [Documentation overview](https://www.socialfetch.dev/docs.mdx) — top-level orientation (markdown).
- [Quickstart](https://www.socialfetch.dev/docs/quickstart.mdx) — authenticate with `x-api-key`, validate auth with `whoami`, and understand the JSON envelope.
- [SDK](https://www.socialfetch.dev/docs/sdk.mdx) — official TypeScript SDK guide, including `SocialFetchClient`, `Result`, and `unwrap()`.
- [Capability matrix](https://www.socialfetch.dev/docs/capability-matrix.mdx) — every operation with identifiers, pagination, outcomes, media download, credits, and its SDK method. Generated from OpenAPI, so use it for route selection instead of scanning individual pages.
- [Recipes](https://www.socialfetch.dev/docs/recipes.mdx) — copyable workflows (brand monitoring, transcripts, Ad Library, creator scoring, Reddit research) with credit callouts and SDK examples.
- [Integrations](https://www.socialfetch.dev/docs/integrations.mdx) — MCP for AI clients, n8n verified node, Apify Store Actors, Make custom app, SDK, and REST API connection paths.
- [MCP product page](https://www.socialfetch.dev/mcp) — hosted MCP overview, OAuth, Skills install.
- [MCP integration](https://www.socialfetch.dev/docs/integrations/mcp.mdx) — hosted `/mcp` server, OAuth, Cursor/VS Code/Claude install snippets, 910 endpoint tools, plus docs_search/docs_read for implementation help.
- [n8n integration](https://www.socialfetch.dev/docs/integrations/n8n.mdx) — install `n8n-nodes-socialfetch`, credentials, and workflow examples.
- [Apify integration](https://www.socialfetch.dev/docs/integrations/apify.mdx) — Store Actors under @social-fetch, PPE billing, dataset export, and quick start.
- [Make integration](https://www.socialfetch.dev/docs/integrations/make.mdx) — custom app modules for Make scenarios, API key credentials, and module catalog.
- [`/llms-endpoints.txt`](https://www.socialfetch.dev/llms-endpoints.txt) — every documented operation with a direct link to that route's agent-readable markdown page (prefer this over parsing OpenAPI).
- [`/llms-{platform}.txt`](https://www.socialfetch.dev/llms-tiktok.txt) — per-platform endpoint files generated from OpenAPI (parameters, credits, curls).
- [`/agents.txt`](https://www.socialfetch.dev/agents.txt) — agent crawl/onboarding file with capabilities, auth rules, and allowlist.
- [`/llms.json`](https://www.socialfetch.dev/llms.json) — structured machine-readable operation inventory with parameter names, pagination, outcomes, credits, and SDK mapping.
- [API reference hub](https://www.socialfetch.dev/docs/api.mdx) — human-friendly index of operations with links into generated pages.
- [Errors](https://www.socialfetch.dev/docs/errors.mdx) — shared error envelope and HTTP status guidance.
- [Credits](https://www.socialfetch.dev/docs/credits.mdx) — metering, `402`, and planning batch jobs.
- Outcome semantics such as `found`, `not_found`, and `private` are documented in [Errors](https://www.socialfetch.dev/docs/errors.mdx) and on operation pages when present in the OpenAPI contract.

## Markdown docs convention

- Every docs page has a markdown twin: append **`.mdx`** to the docs pathname (for example `/docs/quickstart` → `/docs/quickstart.mdx`).
- Agents that send `Accept: text/markdown` on `/docs/**` HTML URLs may receive markdown directly (same URL, `Vary: Accept`).
- Published blog posts use the same convention: `/blog/{slug}` → `/blog/{slug}.mdx`, or `Accept: text/markdown` on the HTML URL (`Vary: Accept`).

---
# List Substack publication posts (https://www.socialfetch.dev/docs/api/v1/substack/publications/publication/posts/get)

## Summary

List the posts in a Substack publication archive.

**Tags:** `Substack`

## HTTP

- **Method:** GET
- **Path:** `/v1/substack/publications/{publication}/posts`
- **Base URL:** `https://api.socialfetch.dev`

## Capability summary

- **SDK mapping:** `client.substack.listPublicationPosts({ publication: "astralcodexten" })`
- **Accepted identifiers:** `publication` (path), `query` (query)
- **Pagination:** cursor via `cursor`, next cursor: `data.page.nextCursor`, has more: `data.page.hasMore`
- **Business outcome field:** `data.lookupStatus` with values `found`, `not_found`, `restricted`

## Credits

- **Base:** 1 credit per successful lookup.
- **Maximum on success (200):** 1 credit.
- **Failed requests (`lookup_failed`, `503`):** not charged.
- **Authoritative field:** `meta.creditsCharged`.

## Authentication

- **`x-api-key`**: API key (`sfk_...`)

## Parameters

### `publication` (path)

- **Required:** yes
- **Constraints:** type `string`; minLength: 1; maxLength: 400
- **Description:** A publication: its numeric id (`89120`), its Substack subdomain (`astralcodexten`), its host (`www.astralcodexten.com`) or its URL. A numeric id is refused with a 400 on the routes that need a subdomain, host or URL.

### `sort` (query)

- **Required:** no
- **Constraints:** type `string`; enum: new, top, pinned; default: `new`
- **Description:** Order. `oldest` is not supported.

### `query` (query)

- **Required:** no
- **Constraints:** type `string`; minLength: 1; maxLength: 200
- **Description:** Only posts whose text matches this string.

### `section` (query)

- **Required:** no
- **Constraints:** type `integer`; minimum: 0
- **Description:** Only posts in this section id (from the publication's sections).

### `page` (query)

- **Required:** no
- **Constraints:** type `integer`; default: `0`; minimum: 0; maximum: 100000; nullable
- **Description:** Page number, 0 to 100,000; leave it at 0 and follow `page.nextCursor`. A page above 0 is refused with a 400 because the archive pages by cursor.

### `cursor` (query)

- **Required:** no
- **Constraints:** type `string`; maxLength: 4096
- **Description:** Opaque cursor from the previous page's `page.nextCursor`. Omit it for the first page.

### `limit` (query)

- **Required:** no
- **Constraints:** type `integer`; default: `23`; minimum: 1; maximum: 23
- **Description:** Rows to return, 1 to 23.

## Pagination

This endpoint uses **cursor-based pagination** via the `cursor` query parameter.

- Read **hasMore** from `data.page.hasMore`.
- When that value is `true`, read **nextCursor** from `data.page.nextCursor` and pass it as the `cursor` query parameter on the **next** request (URL-encode when building a query string).
- Omit `cursor` on the **first** request.
- Stop when **hasMore** is `false` or **nextCursor** is null (end of list).

## Responses (status codes)

- **200**: Substack posts.
- **400**: Invalid request
- **401**: Missing or invalid API key
- **402**: Insufficient credits
- **500**: Unexpected or billing error
- **502**: Lookup could not be completed.
- **503**: Service temporarily unavailable; safe to retry with backoff.

## Response body (200)

Substack posts.

### Field outline

- **data** (required) — type `object`. Endpoint-specific response payload.
  - **lookupStatus** (required) — type `string`; enum: found, not_found, restricted. Whether the publication was found.
  - **restrictedReason** (required) — type `string`; enum: invite_only, flagged, paid, null; nullable. Why the publication is restricted, when it is.
  - **publicationId** (required) — type `integer`; nullable. Numeric publication id.
  - **posts** (required) — type `array`. The archive rows on this page.
    - _items:_
      - **id** (required) — type `integer`. Numeric post id.
      - **publicationId** (required) — type `integer`; nullable. Numeric publication id.
      - **slug** (required) — type `string`; nullable. The post's URL slug.
      - **title** (required) — type `string`; nullable. The post's title.
      - **subtitle** (required) — type `string`; nullable. The post's subtitle.
      - **description** (required) — type `string`; nullable. The post's short description.
      - **kind** (required) — type `string`; nullable. `newsletter`, `podcast`, `video` or `restack`.
      - **audience** (required) — type `string`; nullable. `everyone`, `only_paid`, `only_subscribers` or another value Substack uses.
      - **isPaywalled** (required) — type `boolean`; nullable. Whether the post is paid.
      - **url** (required) — type `string`; nullable. Canonical post URL.
      - **publishedAt** (required) — type `string`; nullable. ISO 8601 timestamp, or null when Substack does not publish one.
      - **updatedAt** (required) — type `string`; nullable. ISO 8601 timestamp, or null when Substack does not publish one.
      - **language** (required) — type `string`; nullable. The post's language code.
      - **bodyHtml** (required) — type `string`; nullable. Full body HTML for a free post; the preview only when `bodyIsPreview` is true.
      - **bodyIsPreview** (required) — type `boolean`. True when the audience is not `everyone`.
      - **previewText** (required) — type `string`; nullable. The public preview text.
      - **wordCount** (required) — type `integer`; nullable. The post's word count.
      - **commentCount** (required) — type `integer`; nullable. The number of comments on the post.
      - **replyCount** (required) — type `integer`; nullable. Replies to comments on the post.
      - **reactionCount** (required) — type `integer`; nullable. The number of reactions to the post.
      - **reactions** (required) — type `object`. Emoji to reaction count.
      - **restackCount** (required) — type `integer`; nullable. The number of restacks.
      - **commentPermission** (required) — type `string`; nullable. Who may comment on the post.
      - **coverImageUrl** (required) — type `string`; nullable. The post's cover image URL.
      - **coverImageIsSquare** (required) — type `boolean`; nullable. Whether the cover image is square.
      - **coverImageIsExplicit** (required) — type `boolean`; nullable. Whether the cover image is explicit.
      - **isGeoblocked** (required) — type `boolean`; nullable. Whether the post is geoblocked.
      - **blockedCountries** (required) — type `array`. Countries where the post is blocked.
        - _items:_
          - type `string`
      - **liveStreamId** (required) — type `string`; nullable. The live stream id, when the post is a live stream.
      - **isPublished** (required) — type `boolean`; nullable. Whether the post is published.
      - **isPinned** (required) — type `boolean`; nullable. Whether the post is pinned.
      - **seoTitle** (required) — type `string`; nullable. The title shown to search engines.
      - **seoDescription** (required) — type `string`; nullable. The description shown to search engines.
      - **socialTitle** (required) — type `string`; nullable. The title used for social previews.
      - **previousSlug** (required) — type `string`; nullable. The previous post's slug.
      - **nextSlug** (required) — type `string`; nullable. The next post's slug.
      - **section** (required) — type `object`; nullable. The section the post belongs to.
      - **tags** (required) — type `array`. The post's tags.
        - _items:_
      - **authors** (required) — type `array`. The post's authors.
        - _items:_
      - **podcast** (required) — type `object`; nullable. Podcast metadata, when the post is an episode.
      - **audio** (required) — type `object`; nullable. Audio, when the post has any.
      - **video** (required) — type `object`; nullable. Video, when the post has any.
  - **page** (required) — type `object`. Cursor pagination state for a publication archive page.
    - **offset** (required) — type `integer`; minimum: 0. The offset sent with this request, 0 on a cursor page.
    - **limit** (required) — type `integer`; minimum: 0. The page size requested.
    - **hasMore** (required) — type `boolean`. True when `nextCursor` holds another page.
    - **nextOffset** (required) — type `integer`; minimum: 0; nullable. Always null. Deeper offsets are no longer served; follow `nextCursor`.
    - **nextCursor** (required) — type `string`; nullable. Opaque cursor for the next page; null on the last page.
- **meta** (required) — type `object`. Metadata describing the request and billing outcome.
  - **requestId** (required) — type `string`; minLength: 1. Unique request identifier for tracing this API call.
  - **creditsCharged** (required) — type `integer`; minimum: 0. Credits charged for this request.
  - **version** (required) — type `string`; enum: v1. Public API version that served the response.

### Example JSON (found)

```json
{
  "data": {
    "lookupStatus": "found",
    "restrictedReason": null,
    "publicationId": 89120,
    "posts": [
      {
        "id": 223080029,
        "publicationId": 89120,
        "slug": "open-thread-458",
        "title": "Open Thread 458",
        "subtitle": "...",
        "description": "...",
        "kind": "newsletter",
        "audience": "everyone",
        "isPaywalled": false,
        "url": "https://www.astralcodexten.com/p/open-thread-458",
        "publishedAt": "2026-11-02T05:04:37.420Z",
        "updatedAt": null,
        "language": null,
        "bodyHtml": null,
        "bodyIsPreview": false,
        "previewText": null,
        "wordCount": 195,
        "commentCount": 474,
        "replyCount": 44,
        "reactionCount": 59,
        "reactions": {
          "❤": 59
        },
        "restackCount": 2,
        "commentPermission": "everyone",
        "coverImageUrl": "https://substack-post-media.s3.amazonaws.com/public/images/9d8ea239-2d80-4635-9f2b-5eca37328062_1536x1024.png",
        "coverImageIsSquare": false,
        "coverImageIsExplicit": false,
        "isGeoblocked": false,
        "blockedCountries": [],
        "liveStreamId": null,
        "isPublished": null,
        "isPinned": false,
        "seoTitle": null,
        "seoDescription": null,
        "socialTitle": "Open Thread 458",
        "previousSlug": null,
        "nextSlug": null,
        "section": null,
        "tags": [],
        "authors": [
          {
            "id": 12009663,
            "name": "Scott Alexander",
            "handle": "astralcodexten",
            "slug": null,
            "bio": null,
            "photoUrl": "https://substackcdn.com/image/fetch/f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fbucketeer-e05bbc84-baa3-437e-9518-adb32be77984.s3.amazonaws.com%2Fpublic%2Fimages%2F7b500d22-1176-42ad-afaa-5d72bc36a809_44x44.png",
            "badge": null,
            "badges": null,
            "bestsellerTier": 1000,
            "primaryPublication": null
          }
        ],
        "podcast": {
          "episodeNumber": null,
          "seasonNumber": null,
          "episodeType": null
        },
        "audio": {
          "url": null,
          "durationSeconds": null,
          "fileSizeBytes": null,
          "mediaType": null,
          "episodeImageUrl": null,
          "items": [
            {
              "postId": 223080029,
              "voiceId": "en-US-OnyxTurboMultilingualNeural",
              "audioUrl": "https://substack-video.s3.amazonaws.com/video_upload/post/223080029/tts/115189ed-03ba-445e-9698-4930d6dc7cee/en-US-OnyxTurboMultilingualNeural.mp3",
              "type": "tts",
              "status": "completed"
            }
          ]
        },
        "video": null
      }
    ],
    "page": {
      "offset": 0,
      "limit": 23,
      "hasMore": false,
      "nextOffset": null,
      "nextCursor": null
    }
  },
  "meta": {
    "requestId": "req_01example_substack_publications_publication_posts",
    "creditsCharged": 1,
    "version": "v1"
  }
}
```

### Machine-readable error codes

When an error JSON body is returned, it may include one of these `error.code` values (derived from the OpenAPI schemas for this operation; additional codes may exist at runtime):

- `bad_request`

## Error handling & retries

Interpret HTTP status codes using the descriptions below. Do not assume a JSON body unless the OpenAPI schema defines one for that status.

- **400**: Invalid request **Retry:** Fix the request; retrying the same invalid payload will not help.
- **401**: Missing or invalid API key **Retry:** Fix the API key first; retrying without changes will not help.
- **402**: Insufficient credits **Retry:** Do not retry without resolving billing/credits (retrying the same request will not help).
- **500**: Unexpected or billing error
- **502**: Lookup could not be completed. **Retry:** May be transient; a few retries with backoff are reasonable.
- **503**: Service temporarily unavailable; safe to retry with backoff. **Retry:** Usually safe to retry with exponential backoff and jitter.

### Suggested client defaults

- Send the API key using the `x-api-key` header on every request.
- On `503` (and sometimes `502`), retry with backoff; cap retries and surface a clear error to the user.
- On `402`, surface an actionable billing message rather than blind retries.

## Examples

### TypeScript SDK

```typescript
import { SocialFetchClient } from "@socialfetch/sdk";

const client = new SocialFetchClient({
  apiKey: process.env.SOCIALFETCH_API_KEY!,
});

const result = await client.substack.listPublicationPosts({
  publication: "astralcodexten",
});

if (!result.ok) {
  console.error(result.error);
} else {
  console.log(result.value.data);
}
```

### Node.js

```javascript
const response = await fetch(
  "https://api.socialfetch.dev/v1/substack/publications/astralcodexten/posts",
  {
    headers: {
      "x-api-key": "YOUR_API_KEY"
    }
  }
);

const data = await response.json();
console.log(data);
```

### cURL

```bash
curl "https://api.socialfetch.dev/v1/substack/publications/astralcodexten/posts" \
  -H "x-api-key: YOUR_API_KEY"
```

### Python

```python
import requests

response = requests.get(
    "https://api.socialfetch.dev/v1/substack/publications/astralcodexten/posts",
    headers={"x-api-key": "YOUR_API_KEY"},
)
data = response.json()
print(data)
```

### Example: next page (pagination)

After a successful response, if pagination is not finished, request the next page using `cursor` (URL-encode when composing the query string):

```javascript
const previous = await response.json();
const nextCursor = previous?.data?.page?.nextCursor;
const hasMore = previous?.data?.page?.hasMore;
if (!hasMore || nextCursor == null) {
  // no more pages
} else {
  const nextUrl = new URL("https://api.socialfetch.dev/v1/substack/publications/value/posts");
  nextUrl.searchParams.set("cursor", nextCursor);
  // optionally preserve sort: nextUrl.searchParams.set("sortBy", "latest");
  const nextResponse = await fetch(nextUrl.toString(), {
    headers: { "x-api-key": "YOUR_API_KEY" },
  });
  const nextData = await nextResponse.json();
}
```