The social media MCP server
One hosted server that lets Claude, ChatGPT, Cursor or any MCP client draft and schedule posts and threads to X, LinkedIn, Bluesky and Mastodon. Sign in with Postbase: no API key, and every post lands on a calendar you can check.
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Claude scheduling through Postbase, live on your calendar
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PostbaseThe server at a glance
- Endpoint
- https://mcp.postbase.so/mcp, over Streamable HTTP.
- Sign-in
- OAuth ("Sign in with Postbase"), so there's no key to paste. Or an API key from the AI & API page.
- Scope
- Each connection is tied to one workspace. Revoke it from the AI & API page at any time.
- Limits
- 60 posts an hour and 120 requests a minute per workspace, shared with the REST API.
Four tools, nothing destructive
The agent can read your channels and queue, create drafts and scheduled posts, and cancel one before it goes out. It can't delete anything.
list_channelsRead onlyThe accounts connected to the workspace: id, network, handle and status. The agent calls it first to get channel ids.
No arguments.
create_postWritesSaves 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, and scheduled_at (ISO 8601 with an offset) or schedule_in_minutes. Leave both times out to save a draft.
list_scheduledRead onlyPosts 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_postWritesCancels a scheduled post before it goes out. It goes back to being a draft, so nothing is deleted.
post_id, from list_scheduled.
Per network
What create_post does on each network, and what it checks first.
- X MCP server
280 characters per post, counted the way X counts: links are 23 and most emoji are 2.
- LinkedIn MCP server
Up to 3,000 characters. Only the first few lines show before "see more".
- Bluesky MCP server
300 characters per post, counted as you'd count them by eye.
- Mastodon MCP server
500 characters per post, the default on most instances.
Two ways to connect
Most AI tools take the hosted URL and sign you in with OAuth. If yours only runs local servers, use the npm package with an API key.
Hosted
RecommendedPaste the server URL into Claude, ChatGPT, Cursor or any client that supports remote servers, then sign in with Postbase. No key to copy or store.
https://mcp.postbase.so/mcp
Local
API keyFor clients that only run local servers: create a key on the AI & API page and run the open-source package with npx. Same four tools.
npx @postbasehq/mcp
Setup for your AI tool
Step-by-step guides, each about a minute.
- Claude
Add Postbase as a connector and let Claude post.
- ChatGPT
Add Postbase as an MCP app and let ChatGPT post.
- Claude Code
One command, then post straight from your terminal.
- Cursor
Install in one click and post from Cursor's agent.
- VS Code
Let GitHub Copilot draft and schedule your posts.
- Windsurf
Give Cascade a publish button for every network.
- Gemini CLI
One command, then schedule posts from Gemini CLI.
Frequently asked questions
What is the Postbase MCP server?
A hosted Model Context Protocol server that lets AI tools like Claude, ChatGPT, Cursor and Claude Code list your social channels, save drafts, schedule posts and threads, and cancel scheduled posts. Everything it creates shows up on your Postbase calendar.
Which networks can an AI post to through it?
X, LinkedIn, Bluesky and Mastodon. The tools send text and threads, so TikTok and YouTube, which need a video, can only be saved as drafts: add the video in Postbase and schedule it from there.
Do I need an API key?
No. Add https://mcp.postbase.so/mcp to your AI tool and sign in with Postbase. If your tool can't do OAuth, create an API key on the AI & API page and run the server locally with npx @postbasehq/mcp.
Can the agent delete posts?
No. It can create drafts and scheduled posts, list them and cancel a scheduled one, which turns it back into a draft. There's no tool that deletes anything or publishes past your review of the calendar.
Is it open source?
Yes. The npm package is at github.com/postbasehq/mcp and the hosted server is part of the Postbase app at github.com/postbasehq/postbase, both under AGPL-3.0. It's also in the official MCP registry as io.github.postbasehq/postbase.
Is there a free plan?
Every plan starts with a 7-day free trial and includes the MCP server and API. Drafts work without a plan; scheduling needs an active plan or trial.
Ready to get started?
Connect your agent in a minute. It drafts and schedules, and you see every post in your calendar.
Cancel anytime · or self-host for free
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