Post to X from Codex with the MCP server

Attach PostWharf's MCP server to Codex once, then publish or schedule X posts, threads and video by asking for them — and get a receipt saying what actually landed.

Connect it

Point the connector at the hosted server and the tools appear alongside the rest. One workspace key scopes every call to a single brand, so Codex can only ever reach the accounts in that workspace — not every account you run.

# Point the connector at:
https://mcp.postwharf.com/mcp
# with the header:
Authorization: Bearer YOUR_WORKSPACE_KEY

Ask for an X post

Once the server is attached the ask is a prompt, not a form — alongside whatever else the agent has been asked to finish:

"Turn these release notes into a four-post thread and queue it for 9am tomorrow."

Codex finds your connected X channel, checks the text against the 280-character ceiling before anything is queued, and hands back the queued time. Nothing publishes because a model decided it should.

Treat the post as the last step of a task rather than a task of its own. The agent already knows what it just did, which is most of what the announcement needs to say.

What X accepts

Character limit280
Counted onone post in a thread
Formatsposts, threads and video

A post takes up to four images or one video; X does not accept both in one post.

What comes back

Every post carries a delivery receipt per channel: the state, the live URL once it is out, and the platform's own reason if it failed. Deliveries are re-checked after publishing, so an X post removed later stops reporting as live instead of sitting in your history as a success. Ask Codex for the status and it reads that receipt back rather than guessing.

Questions

Can Codex post to X automatically?

Yes. Connect the PostWharf MCP server to Codex and it can publish or schedule to a connected X channel, then read the delivery receipt back. The workspace key limits it to the accounts in one workspace, and you keep the approval step.

What do I need before X will work?

A post takes up to four images or one video; X does not accept both in one post. Once the channel is connected in PostWharf, Codex reaches it the same way it reaches every other network.

How long can an X post be?

280 characters, counted on one post in a thread. PostWharf checks that before the post is queued, so an over-length post is refused immediately rather than failing at X after everything else in the same batch has already published.