The X MCP server
Let Claude, ChatGPT, Cursor or any MCP client schedule tweets and threads on X through the official API, without an X developer account of your own.
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Claude scheduling to X through Postbase
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PostbaseHow posting to X works
- Length
- 280
- Characters per post, counted the way X counts: links are 23 and most emoji are 2.
- Threads
- 25 posts
- Send a thread array and Postbase publishes it as a chain of replies.
- Links
- 20 to 75 a month
- X charges per post with a link, so those are capped by plan. Plain posts and threads are unlimited.
- API access
- Included
- Postbase posts through its own X API app, so you don't need X API keys or a paid developer tier.
Problems go back to the agent, not out to your followers
- Too long
- A scheduled post over 280 weighted characters is refused when the agent calls the tool, with the reason, so it can shorten it.
- In the past
- A time in the past is refused rather than posted straight away.
- Link allowance
- Near the monthly link allowance, the call returns a warning the agent can pass on. Linked posts past the allowance aren't sent until it resets.
The tools
The same ten tools on every network.
list_channelsRead onlyList channelsPostbaseThe accounts connected to the workspace: id, network, handle and status. The agent calls it first to get channel ids.
No arguments.
create_postWritesCreate or schedule a postPostbaseSaves a draft, or schedules a post or a thread, on one or more channels. The post lands on your Postbase calendar and publishes through each network's official API.
body or thread, channel_ids, scheduled_at (ISO 8601 with an offset) or schedule_in_minutes, media_ids from list_media or media_urls, channel_bodies for per-channel text, and an idempotency_key so a retried call can't post twice. Leave both times out to save a draft.
get_postRead onlyGet a postPostbaseOne post and how it went on each channel: published with its live link, or failed with the reason and when it will be retried.
post_id, from create_post or list_scheduled.
update_postWritesEdit a postPostbaseEdits or reschedules a draft or scheduled post before it goes out. Only the fields you pass change.
post_id, plus any of create_post's fields. scheduled_at null turns it back into a draft.
retry_postWritesRetry failed channelsPostbaseSends a post again to the channels where it failed. Channels where it already published are left alone.
post_id.
get_analyticsRead onlyGet post analyticsPostbaseHow published posts performed: impressions, likes, comments, shares and saves per channel, with totals for the range.
from and to (YYYY-MM-DD, default the last 30 days), or post_id; channel_id, platform, sort (date or a metric), order, limit.
list_mediaRead onlyList mediaPostbaseThe images and videos in your Postbase media library, newest first. The agent passes their ids to create_post to attach them.
type (optional): image or video. search (optional): part of a file name.
add_mediaWritesAdd media from a URLPostbaseAdds an image or video to your media library from a public link, for attaching to posts.
url (https). name (optional).
list_scheduledRead onlyList scheduled postsPostbasePosts in the workspace with their text, time and channels. Scheduled posts by default, or drafts, published or failed ones.
status (optional): scheduled, draft, published or failed.
cancel_postWritesCancel a scheduled postPostbaseCancels a scheduled post before it goes out. It goes back to being a draft, so nothing is deleted.
post_id, from list_scheduled.
Frequently asked questions
Do I need an X developer account?
No. You connect your X account to Postbase with X's own sign-in, and Postbase publishes through its API app. The AI tool only ever talks to Postbase.
Can it attach images or video to a tweet?
Yes. Upload them to your Postbase media library and ask the agent to attach them: up to four images, or one video or GIF, per post.
Can it reply to or like other people's posts?
No. The server schedules your own posts and threads. There are no tools for replies to others, likes, follows or DMs.
Related
- Claude + X
Set up Claude to post to X.
- Claude Code + X
Set up Claude Code to post to X.
- Cursor + X
Set up Cursor to post to X.
- LinkedIn MCP server
Characters per post. Only the first few lines show before "see more".
- Bluesky MCP server
Characters per post, counted as you'd count them by eye. Links are made clickable for you.
- Mastodon MCP server
Characters per post, the default on most instances. Hashtags work as you type them.
- YouTube MCP server
The agent finds the video with list_media and attaches it by id. Postbase uploads it to YouTube when it's due.
- X (Twitter) scheduler
Tweets and threads up to 25 posts, with images and video.
From the blog
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