Post to Mastodon from Claude
Connect Claude to Mastodon with the Postbase MCP server and schedule Mastodon posts and threads from a chat. No API key, and every post lands on a calendar you can check.
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Connect Claude from the Developers page
Use your API key to automate Postbase — hook up an AI agent over MCP, script it from the CLI, or call the REST API directly.
API keys
A key authenticates the MCP server, the REST API, and the CLI. Shown once — store it safely.
pb_live_…9c1eMCP client configuration
Connect the Postbase MCP server to your AI tool so it can schedule and publish for you.
Authentication
No key to manage — your tool signs in through Postbase.
Client
In Claude: Settings → Connectors → Add custom connector, and paste this URL. You'll sign in to Postbase in a browser window — no API key.
https://mcp.postbase.so/mcpAdd to ClaudeCopyConnected apps
Tools you've signed in to Postbase from. Revoking cuts off their access immediately.
Set up in three steps
- 1
Connect Mastodon to Postbase
On your instance, open Preferences → Development, create an application with read and write access and copy its access token. Paste it with your instance URL on the Channels page.
- 2
Add the connector
In Claude on the web or desktop, open Settings → Connectors → Add custom connector. Name it Postbase and paste the server URL.
- 3
Ask for Mastodon posts and threads
Tell Claude what to post on Mastodon and when. Everything it schedules shows up in your Postbase calendar.
https://mcp.postbase.so/mcpWhat to ask Claude
A few Mastodon requests that work well.
“Write a plain, friendly Mastodon post about our open-source release, with two relevant hashtags.”
“Turn these release notes into a short Mastodon thread and schedule it for 10am.”
“What have I got scheduled on Mastodon this week?”
How Claude's posts work on Mastodon
- Length
- 500 characters per post, the default on most instances.
- Instances
- Works with any server you've connected in Postbase: mastodon.social, fosstodon.org or your own.
- Threads
- Ask for a thread and each post is published as a reply to the one before.
Tips for better Mastodon posts
- Mastodon readers expect plain, human posts. Ask for no marketing language.
- Use a few relevant hashtags at the end: they're how people find posts on Mastodon.
- Ask for a separate, shorter version for X rather than sharing the 500-character text.
Frequently asked questions
Does it work with my Mastodon instance?
Yes. Connect your account in Postbase with your instance URL and an access token, and the agent can post to it like any other channel.
Can it post to Mastodon and Bluesky together?
Yes. Ask for both, and it can send one post to both channels or a separate version to each.
Does Claude need my Mastodon password?
No. You connect Mastodon to Postbase once, and Claude signs in to Postbase, not to Mastodon. You can revoke Claude's access from the Developers page at any time.
Can Claude delete my Mastodon posts?
No. It can list channels, create drafts and scheduled posts, list the queue and cancel a scheduled post. There's no tool for deleting anything.
Related
Ready to get started?
Connect Claude in a minute. It writes and schedules your Mastodon posts, and you see every one in your calendar.
Cancel anytime · or self-host for free
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pb_live_Qm7xT2vLr9KcH0sWbN8y…4f2aCopyAuthentication
Client