Substack MCP vs Upload Post
A side-by-side look at the Substack MCP and Upload Post MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Substack MCP for social media work as a local process; choose Upload Post for social media as a local process. You can also run both side by side in one mcpServers block.
Which MCP server should you choose?
Choose Substack MCP when
- You need dedicated capabilities in the Social Media domain.
- You prefer a local stdio subprocess transport.
- Its auth model fits you: other.
- You have the keys it needs:
SUBSTACK_PUBLICATION_URL, SUBSTACK_SESSION_TOKEN, SUBSTACK_USER_ID, SUBSTACK_MCP_HOME. - You want tools like
get_subscriber_count, list_published_posts, list_drafts.
Choose Upload Post when
- You need dedicated capabilities in the Social Media domain.
- You prefer a local stdio subprocess transport.
- You have the keys it needs:
UPLOAD_POST_API_KEY, UPLOAD_POST_STUDIO_CLIENTS. - You want tools like
upload_video, upload_photos, upload_text.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Social Media | Social Media |
| Quality signal | 68/100 · Great | 64/100 · Good |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | other | Not declared |
| Pricing | Free | Not declared |
| Required env vars | SUBSTACK_PUBLICATION_URLSUBSTACK_SESSION_TOKENSUBSTACK_USER_IDSUBSTACK_MCP_HOME | UPLOAD_POST_API_KEYUPLOAD_POST_STUDIO_CLIENTS |
| Verified owner | Community listing | Community listing |
| GitHub stars | 44 | 10 |
| Directory activity | 6 views 0 installs 0 upvotes | 1 views 0 installs 0 upvotes |
| Tools | 14 | 57 |
| Full listing | View Substack MCP | View Upload Post |
Tools & capabilities
Substack MCP tools 14
get_subscriber_countGet the current subscriber count for your Substack publication. Returns `precision`: 'exact' when the API reports a true count, 'approximate' when only Substack's rounded value is available (the real number is that or higher — render it hedged, e.g. '1,000+'), or 'unavailable' with count -1. Never treat an approximate value as exact.list_published_postsList published posts with pagination. Returns title, date, slug, and URL for each post.list_draftsList draft posts. Returns title, creation date, and audience for each draft.get_postGet the full content of a published post by ID. Returns title, body HTML, metadata.get_draftGet the full content of a draft post by ID. Returns title, body, metadata.get_post_commentsGet comments on a published post. Returns commenter name, comment body, date, and reaction counts.get_sectionsList your publication's sections (categories). Returns each section's id and name. Use a section id as `section_id` when creating or updating a draft to file it under that section.get_post_analyticsGet performance stats (views, emails sent/delivered/opened, signups, subscribes, estimated value, comments, reactions) for a published post by ID. Substack has no per-post stats endpoint, so this searches your 500 most recent published posts for the ID; returns a not-found note if it isn't among them.list_scheduled_postsList posts scheduled for future publication, soonest first. Read-only visibility into what's queued — scheduling itself is done in Substack's editor (this server does not schedule, publish, or delete long-form posts). Returns id, title, audience, and scheduled time (`trigger_at`).create_draftCreate a new draft post. Accepts markdown body which is converted to Substack's format. Does NOT publish — creates a draft only.update_draftUpdate an existing draft post. Only works on unpublished drafts. Accepts markdown body.upload_imageUpload an image to Substack's CDN. Provide exactly one of `image_base64` (a base64 data URI) or `image_path` (a local file path). Returns a hosted image URL that is publicly fetchable by anyone with the link (an unlisted asset — not attributed to you or added to your feed).- +2 more on the listing page
Upload Post tools 57
upload_videoPublish a video to one or more platforms. Use `videoPathOrUrl` only for public/signed HTTPS URLs, or for absolute local paths when the MCP server runs on the same machine as the file. `videoBase64` is only for clients that can provide raw bytes directly and is capped by UPLOAD_POST_MAX_INLINE_MB (default 100). Returns a `request_id` you can poll with `get_status`. Supports per-platform overrides (tiktokPrivacyLevel, youtubePrivacyStatus, youtubePlaylistId, youtubeThumbnailUrl, youtubeTags, facebookPageId, instagramMediaType, etc.). Reddit posting is currently unavailable (error_code=reddit_unavailable) until the Reddit app is restored. Do not use reddit as a publish target. A hosted MCP server cannot read files on the user's machine or chat attachments (`/mnt/data`, sandbox paths). To publish a local file: (1) if this client can run HTTP requests itself (for example a coding agent with a shell), stage it with `create_media_upload` (returns `upload_id` + `upload_url`), PUT the raw file bytes to `upload_url` with the same Content-Type, call `complete_media_upload` and pass the returned `media_url` as the media URL; (2) otherwise ask the user for a public HTTPS URL of the file, or tell them to publish it from the dashboard at https://app.upload-post.com. Staged media is deleted after 24 hours.upload_photosPublish one or more photos (single image or carousel). Each item in `photosPathsOrUrls` may be a public URL or a local path. Reddit posting is currently unavailable (error_code=reddit_unavailable) until the Reddit app is restored. Do not use reddit as a publish target.upload_textPublish a text-only post. `linkUrl` (or platform-specific *LinkUrl) attaches a link preview where supported. Reddit posting is currently unavailable (error_code=reddit_unavailable) until the Reddit app is restored. Do not use reddit as a publish target.upload_documentPublish a document (PDF / PPT / PPTX / DOC / DOCX) to LinkedIn. Title is required.get_statusCheck the status of an async upload by `request_id`. Poll this until `status` is 'success' or 'failed'.get_job_statusCheck the status of a scheduled or queued upload by `job_id`. Use this for posts created with `addToQueue` or `scheduledDate`.get_historyPaginated history of uploads across all profiles.get_mediaRetrieve recent media (videos, photos, text posts) pulled directly from a profile's connected social accounts. Supports instagram, tiktok, youtube, linkedin, facebook, x, threads, pinterest, bluesky, reddit. Useful for browsing what already exists on a platform before posting more. Paginated: the response carries `pagination` = { limit, next_cursor, has_more }; pass `next_cursor` back as `cursor` for the next page (the last page returns next_cursor null and has_more false).list_scheduledList all currently scheduled (not-yet-published) posts.cancel_scheduledCancel a scheduled post by its `job_id`.edit_scheduledEdit a pending scheduled post in place, keeping its job ID and media: reschedule it (scheduledDate/timezone) and/or fix its text. `title` and `caption` rewrite the text for EVERY platform of the post; to change only some platforms, send `platformContent` instead, e.g. {"instagram":{"caption":"..."},"tiktok":{"caption":"..."}} — platforms not listed keep their text. First comments cannot be edited on a pending post.get_analyticsAggregated analytics for a profile across selected platforms (followers, views, engagement). Instagram also returns two audience breakdowns with the same shape (age / gender / country / city): `follower_demographics` for the account's followers and `engaged_audience_demographics` for the accounts that engaged with its content.- +45 more on the listing page
Ready-to-paste client configs
Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.
Substack MCP
{
"mcpServers": {
"conorbronsdon-substack-mcp": {
"command": "npx",
"args": [
"-y",
"@conorbronsdon/substack-mcp"
],
"env": {
"SUBSTACK_PUBLICATION_URL": "YOUR_SUBSTACK_PUBLICATION_URL_HERE",
"SUBSTACK_SESSION_TOKEN": "YOUR_SUBSTACK_SESSION_TOKEN_HERE",
"SUBSTACK_USER_ID": "YOUR_SUBSTACK_USER_ID_HERE",
"SUBSTACK_MCP_HOME": "YOUR_SUBSTACK_MCP_HOME_HERE"
}
}
}
}
Upload Post
{
"mcpServers": {
"upload-post": {
"command": "npx",
"args": [
"-y",
"@upload-post/mcp"
],
"env": {
"UPLOAD_POST_API_KEY": "YOUR_UPLOAD_POST_API_KEY_HERE",
"UPLOAD_POST_STUDIO_CLIENTS": "YOUR_UPLOAD_POST_STUDIO_CLIENTS_HERE"
}
}
}
}
Frequently asked questions
Substack MCP is categorized under Social Media and uses a local stdio subprocess. Upload Post belongs to Social Media and uses a local stdio subprocess. Pick Substack MCP for social media work and Upload Post for social media.
Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.
Substack MCP is listed as free. Auth: other. Upload Post has no declared pricing — check the project's own site. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.
Yes. MCP clients support multiple servers: add conorbronsdon-substack-mcp and upload-post as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, Substack MCP has a quality signal of 68/100 (Great) with 6 views, 0 installs and 44 GitHub stars. Upload Post has 64/100 (Good) with 1 views, 0 installs and 10 GitHub stars.
