Let your assistant hold the calendar. You keep the final say on what goes out.

What the assistant can actually do

Five tools, each mapping to something the dashboard already does:

Tool	What it does
list_channels	Your connected accounts, and whether each one is healthy
list_queue	Upcoming scheduled posts
get_best_times	Recommended posting windows for a set of platforms
schedule_post	Stages a scheduled post — never publishes on the spot
reschedule_post	Moves an already-scheduled post to a new time

That list is deliberately short. An assistant with a generic "call any endpoint" tool is hard to reason about and harder to trust; five named tools mean the set of things it can do to your calendar is something you can read in one sitting.

Why writes stage instead of publishing

An assistant that can publish is an assistant that can publish the wrong thing at 2am, to the wrong channel, with no undo. Social platforms do not have a real edit-after-post story, so the damage is permanent.

So schedule_post always produces a scheduled post. It lands on your calendar, it shows up in the dashboard queue, and you can move it or delete it right up to the publish time. If you asked for something in ten minutes, you have ten minutes.

Setting it up in Cursor and ChatGPT

Both follow the same shape as Claude Desktop: find the custom connector or MCP server setting, give it the endpoint, and approve in the browser when it opens.

https://app.postonus.com/api/mcp

No JSON config to edit, and nothing to keep in sync when a token rotates. The dashboard's AI Assistants page lists what you have connected and how much each one is being used, which is usually the fastest way to confirm a new connector took.

What it does not do

Being straight about the edges, since finding them by trial is annoying:

• No media upload. Attaching images or video is the CLI's job (postonus media upload) or the dashboard's.
• No channel connecting. Adding a social account needs an OAuth hop, which belongs in a browser.
• One workspace at a time. It follows your default. Agencies running a workspace per client switch defaults rather than pointing one assistant at several.

If you need any of those from a script, the CLI and API keys cover them.

On "the only one"

Worth saying plainly, because a lot of marketing copy in this category is not: Postonus is not the only scheduler with an MCP server. Buffer, Hootsuite, Metricool, Postiz, and RecurPost all ship one. If you are shopping for MCP alone, you have options.

What we would point at instead is the shape of ours — five tools rather than a thin wrapper, writes that stage instead of publish, and availability on every plan rather than a tier you have to reach first.