Codex + PostAxis

Schedule social media posts with Codex

Codex writes the code; let it write the announcement too. With the PostAxis MCP server, Codex can draft posts from your changes and schedule them to every channel you run.

Two commands, browser sign-in
Works in the Codex CLI and IDE extension
From pull request to post in one prompt

Connect Codex Start for $0

Set up Codex with PostAxis

Plug PostAxis into Codex once, then talk to it like you would to whoever runs your accounts. Every click is in the full guide below.

Plug in about a minute

Step 1 of 2

Add PostAxis to Codex

Two commands: one adds the server, one signs you in. Works in the Codex CLI and the IDE extension, which share the same config.

PostAxis account
A connected social account
Codex installed

Terminal

codex mcp add postaxis --url https://postaxis.io/api/mcp
codex mcp login postaxis

Talk

Step 2 of 2

Then tell Codex what you need

Codex picks the PostAxis tools it needs. Scheduled posts go out on time whether or not the chat is still open.

Try asking

Which accounts can you post to?
What goes out this week?
Keep that one as a draft

Write an X post and a LinkedIn post about the feature in this PR and schedule them for tomorrow 10:00 UTC.

Scheduled both for tomorrow 10:00 UTC. The X version is 201 characters; LinkedIn has a short bullet list of what changed.

via PostAxis

Example answer · lands in your PostAxis calendar

Full setup guide for Codex

Every step from a new PostAxis account to your first scheduled post. Takes about a minute once your accounts are connected. Want ready-made workflows? Read the full Codex guide

1
Create your PostAxis account
Sign up at app.postaxis.io. Every plan starts with a 7-day free trial and includes MCP access with OAuth sign-in. Create an account
2
Connect your social accounts
Open Accounts in PostAxis and connect the networks you want to post to: Instagram, TikTok, YouTube, X, LinkedIn, Facebook, Threads or Telegram. Your agent can only post to accounts connected here, and it never sees your social media passwords. Open Accounts
3
Add the server
Run this in your terminal. It writes PostAxis into ~/.codex/config.toml.
Copy this
```
codex mcp add postaxis --url https://postaxis.io/api/mcp
```
4
Sign in
Run the login command, then approve access on the PostAxis page that opens in your browser.
Copy this
```
codex mcp login postaxis
```
5
Check it’s connected
Start Codex and type /mcp. postaxis should be listed with its tools.
6
Ask Codex to post
Ask from the CLI or the IDE extension. Codex asks for approval before calling tools that create or change posts.

What can Codex do with PostAxis?

Everything PostAxis does in the dashboard that makes sense to do by asking: writing, scheduling, editing, publishing and checking your queue.

Sentences in, posts out

Describe the post in your own words. Codex turns it into posts and PostAxis handles the scheduling.

Every network you run

Instagram, TikTok, YouTube, X, LinkedIn, Facebook, Threads and Telegram, from a single message.

Checked before it’s saved

Caption length, media count, video length and format are checked for every network before anything is saved.

Weeks ahead in one go

Ask for a week or a month. Codex can dry-run up to 50 posts at once, show you the plan, then schedule it.

Your images and video

Attach images and videos from a link, or get a one-time upload link for files on your computer.

Your accounts, your call

Codex signs in as you and can only reach accounts connected in your workspace. Cut it off from Settings whenever you like.

What is Codex?

Codex is OpenAI’s coding agent. It runs in your terminal, in IDEs through an extension and in the cloud, and it can call MCP servers you add to its config.

With PostAxis added, Codex can write the announcement for the change it just made and schedule it to X, LinkedIn and your other channels.

What can you ask Codex to post?

Brief it like a person: what it’s about, where it goes, when. Four requests that work well with Codex:

Release notes
Turn a release into posts
Read CHANGELOG.md, write an X post and a LinkedIn post about this release and schedule both for 17:00 today.
To Codex
From a pull request
Announce what you merged
Summarise the feature in this branch as a short X post and a Threads post, and schedule them for tomorrow at 10:00.
To Codex
Weekly digest
Post a weekly changelog
Summarise this week’s commits as a “what’s new” post and publish it to Telegram and LinkedIn now.
To Codex
Check the queue
Fix what won’t publish
List my scheduled posts for this week and fix any that break Instagram’s or X’s rules.
To Codex

How does Codex talk to PostAxis?

Through MCP, the Model Context Protocol: an open standard for giving AI apps tools. PostAxis runs an MCP server; Codex connects to it and gets 11 tools that work on your account, nothing more. Full MCP reference

From your message to a scheduled post

What happens between you hitting enter and the post showing up in your calendar.

You write one message: what, where, when
Codex looks up your accounts and the limits of each network you named
It drafts a version per network and sends them to PostAxis
PostAxis checks every version and saves it as scheduled, a draft or live
The post sits in your calendar, editable until it goes out

Codex + PostAxis

Server: https://postaxis.io/api/mcp
Transport: Streamable HTTP
Sign-in: OAuth 2.1

Tools Codex discovers

list_workspacesYour PostAxis workspaces
list_accountsConnected social accounts per workspace
get_platform_rulesCaption limits and media rules per network
upload_media_from_urlPull an image or video into your media library
create_upload_linkOne-time link for uploading a local file
create_postDraft, schedule or publish one post
create_posts_bulkSchedule up to 50 posts in one call
list_postsPosts by status or date range
get_postOne post with its per-network status
update_postEdit text, media or time before it goes out
delete_postRemove a draft or scheduled post

Do the Codex CLI and IDE extension share the setup?

Yes. Both read ~/.codex/config.toml, so after codex mcp add and codex mcp login, PostAxis works in the CLI and the IDE extension.

Does Codex write a different version for each network?

It can, and it should: X counts characters, LinkedIn rewards a longer read, Telegram has no title. Name the networks in one request and Codex sends one post with a version per network. PostAxis rejects any version that breaks that network’s limits before it is saved.

Share the 2.0 release with the screenshot from our blog: a punchy line on X, a short story on LinkedIn, the full changelog on Telegram. All at 14:00.

Done. Here’s what I did:

X: 1 post, 212 characters, screenshot attached
LinkedIn: 1 post, 4 short paragraphs, screenshot attached
Telegram: the full changelog, screenshot attached
Scheduled together for 14:00, one post ID

via PostAxis

Example conversation

How does Codex sign in to PostAxis?

Codex signs in to PostAxis, never to your social networks. Your Instagram, X or LinkedIn accounts stay connected to PostAxis, and you can revoke Codex’s access at any time.

Every plan✓ Used by Codex

OAuth sign-in

Codex opens the PostAxis sign-in in your browser
You log in and click Approve
It gets access to your account only, until you revoke it

Best for apps you use yourself: ChatGPT, Claude, Cursor, Codex and most others

API add-on

API key

Create a key under Settings → API keys
Send it as Authorization: Bearer KEY, or in the URL for clients that only take a URL
Revoke the key any time and access stops at once

Best for servers and automations with no browser: n8n, Grok, Manus, headless agents

If something doesn’t work

The most common problems when connecting Codex, and how to fix them.

The agent says no accounts are connected

Connect at least one social account under Accounts in PostAxis. If you use several workspaces, tell the agent which one, for example “use my Acme workspace”.

401 Unauthorized or “sign in again”

The sign-in expired or was revoked. Reconnect from your agent (it opens the PostAxis sign-in again). With an API key, check the key is still active under Settings → API keys.

A post was rejected before saving

PostAxis checks each network’s rules first: caption length, media count, video length and format. The error says what to change; ask the agent to fix it and try again.

Posts are scheduled at the wrong time

Say the timezone in your request, for example “9:00 Europe/Berlin”. Without one, the agent uses the timezone it was told or UTC.

I want to stop an agent from posting

Open Settings → API keys in PostAxis. Revoke the agent under Connected agents, or revoke its API key. It loses access immediately.

Codex and PostAxis: questions

Is Codex the same as ChatGPT here?

They share the PostAxis MCP server, but Codex is OpenAI’s coding agent for the terminal and IDE, while ChatGPT is the chat app. Use whichever you work in.

Where does Codex keep the server config?

codex mcp add writes the server to your Codex config (~/.codex/config.toml). codex mcp login stores the OAuth token.

Can I use an API key?

Yes. Configure the server with an Authorization: Bearer header carrying a PostAxis API key (requires the API add-on).

What is the PostAxis MCP server?

It’s a remote Model Context Protocol server at https://postaxis.io/api/mcp that gives AI agents 11 tools to list your accounts, upload media and create, schedule, edit and delete posts in PostAxis.

Which social networks are supported?

Instagram (posts, Reels, carousels), TikTok (videos and photo posts), YouTube Shorts, X, LinkedIn, Facebook Pages, Threads and Telegram channels.

How much does it cost?

MCP access with OAuth is included in every PostAxis plan, and every plan starts with a 7-day free trial. API keys need the API add-on.

What stops an agent from posting something wrong?

PostAxis checks every post against each network’s rules before saving, the agent can preview bulk plans without saving them, everything shows up in your calendar, and you can revoke an agent at any time in Settings → API keys.