How to post to LinkedIn from Codex CLI
The agent that merged the change can explain it on LinkedIn, with room for 3,000 characters and a link that stays clickable.
How do I post to LinkedIn from Codex CLI?
Add the planpo.st MCP server to Codex CLI, connect LinkedIn once in the dashboard, then ask. The first three steps are one-time.
- 1
Create an API key and add planpo.st to Codex CLI
Make a scoped key in planpo.st under Settings. Add a [mcp_servers.planpost] table to ~/.codex/config.toml, or run codex mcp add and answer the prompts. The hosted form reads the token from the environment variable named in bearer_token_env_var, so export PLANPOST_API_KEY in your shell first.
- 2
Confirm the server is connected
Start Codex and run /mcp to check that planpost is connected.
- 3
Connect LinkedIn
Connect LinkedIn in the dashboard under Connections. A personal profile and a company page are separate connections with separate IDs, and get_connection_link gives the agent a URL to pass to you when one is missing.
- 4
Know what the post needs
A LinkedIn post needs text of 3,000 characters or fewer. Media is optional and nothing in platformSettings is required.
- 5
Ask in your terminal
Say what to post and when. Codex CLI finds the LinkedIn connection, creates the post, and tells you whether it was scheduled or kept as a draft, with the reason.
[mcp_servers.planpost]
url = "https://mcp.planpo.st/mcp"
bearer_token_env_var = "PLANPOST_API_KEY"[mcp_servers.planpost]
command = "npx"
args = ["-y", "planpost-mcp"]
[mcp_servers.planpost.env]
PLANPOST_API_KEY = "pk_live_xxx"Config location: ~/.codex/config.toml, or .codex/config.toml in a trusted project. Replace pk_live_xxx with your own key.
Hosted or local for Codex CLI?
For Codex CLI I would use hosted with bearer_token_env_var, since the config file then holds no secret and can be shared. Use local when you would sooner keep the key in the config file's env table than in your shell profile.
- The hosted form reads the token from an environment variable rather than the file, so export PLANPOST_API_KEY in your shell.
- `codex mcp add` does the same thing interactively if you would rather not edit TOML.
The full walkthrough is on the Codex CLI setup page.
What can Codex CLI do on LinkedIn?
It can publish text posts, single-image posts, multi-image posts of up to 9 images and video posts, to a personal profile or a company page. It cannot post PDF documents, polls or articles.
Text post
3,000Up to 3,000 characters with clickable links. The long cut of an idea belongs here, with platformContent.linkedin holding it when other networks get a shorter one.
Image or images
1 to 9One image, or several as a multi-image post. The first 9 are used.
Video
One video per post. When the first attachment is a video, that file is the post.
Profile or page
Decided by the connection ID. Pass the profile's ID, the page's ID, or both in two posts with different wording.
Attachments are optional on LinkedIn. When a post should carry one, Codex CLI can take it from disk: it calls upload_media for a presigned URL, PUTs the file there with a shell command, and passes the returned asset into create_post. Files already uploaded come back from list_media, ready to reuse.
Which settings does a LinkedIn post take?
The LinkedIn publisher reads nothing from platformSettings. Who the post is from is decided by the connection, and visibility is always public, so the table lists the post fields that do the work.
| Field | Allowed values | If you leave it out | Worth knowing |
|---|---|---|---|
| connectionIds | ID of a profile connection or a company page connection | None, required | This is the profile versus page switch. list_connections returns both with their IDs. |
| platformContent.linkedin | Text, 3,000 characters or fewer | The shared content | Over 3,000 here is rejected with a 400. Shared content over 3,000 saves the post as a draft with char_limit. |
| media, platformMedia.linkedin | Images (1 to 9) or one video | Text post | The first attachment decides the kind of post. Images after the ninth are left out. |
| platformSettings.linkedin.* | Not read | Does not apply | organizationUrn and isPersonal exist on the type and are ignored at publish. Use the connection ID. |
| Visibility | PUBLIC | PUBLIC | Fixed. There is no connections-only option. |
What do I type to post to LinkedIn from Codex CLI?
Plain requests work. Each example lists the tool calls Codex CLI makes in response.
1. Profile and company page, two voices
You say
Read the pull requests merged this week. Write two LinkedIn posts from it: first person for my profile, third person for the company page. Schedule both for Thursday 09:00.
Tool calls
list_connections()
create_post({ content: "<first person>", connectionIds: ["<profile id>"], schedule: "thursday 09:00" })
create_post({ content: "<third person>", connectionIds: ["<page id>"], schedule: "thursday 09:00" })Two scheduled posts on two connections. They are separate posts on purpose, because the wording differs and so will the numbers.
2. A carousel of images
You say
Open RELEASE_NOTES.md. Make a 7-slide carousel from it for LinkedIn and save the post as a draft so I can look first.
Tool calls
generate_carousel({ content: "<source text>", platform: "linkedin", maxSlides: 7 })
render_carousel({ slides: [...], family: "<id from list_carousel_styles>" })
get_carousel_render({ id: "<render id>" })
create_post({ content: "<caption>", media: [<7 assets>], connectionIds: ["<linkedin id>"], schedule: "draft" })Seven rendered PNG slides in your media library and a draft multi-image post. Seven fits; a tenth slide would be dropped, since LinkedIn gets the first 9 images.
3. Post with a tracked link
You say
Use the notes in TODO.md under Done. Write a LinkedIn post that ends with the link to the pricing page and schedule it at the best time this week.
Tool calls
get_best_times({ platform: "linkedin" })
create_post({ content: "<post ending in https://...>", connectionIds: ["<linkedin id>"], scheduledFor: "<ISO time from get_best_times>", campaign: "pricing-update" })A scheduled post with a clickable link and a campaign tag. Payments that follow a click on that link show up next to this post.
What stops a LinkedIn post from Codex CLI?
The tag on a card is the code that comes back in the tool result.
3,000 characters
char_limitChecked when the post is created. Too long and it is saved as a draft with the count, the limit and the field to shorten.
9 images, then it stops
A multi-image post uses the first 9 attachments. Extra images are left out without failing the post, so keep carousels at 9 or fewer.
Do not mix images and video
The first attachment decides the type. An image first makes it an image post; a video first makes it a video post with that one file.
No PDF documents
The swipeable document format is not supported. A rendered image carousel is the nearest thing and it publishes as a multi-image post.
Always public
Posts go out with public visibility. If you need connections-only, post that one by hand.
Profile and page are different connections
Sending a page announcement to your personal profile is one wrong ID away. Have the agent read list_connections back before the first post.
The token comes from your shell
Codex CLIThe hosted config names an environment variable, it does not hold the key. If PLANPOST_API_KEY is not exported in the shell that starts Codex, every call fails with an authorization error.
Can Codex CLI tell me what a LinkedIn post earned?
Yes. Links in LinkedIn posts are clickable, so a tracked link in the post gives a click to match against a later payment, and get_revenue_overview returns the totals and recent transactions. LinkedIn readers are mostly buying for a business, which usually means Stripe on the other end.
Codex CLI and LinkedIn: questions people ask
- How do I post to a company page instead of my profile?
- Pass the page's connection ID. The page and the profile are separate connections, and the post is authored by whichever one the ID belongs to. There is no setting for it.
- Can it post a document carousel?
- Not the PDF kind. It can render up to 9 slides as images and publish them as a multi-image post.
- What happens when Codex CLI sends a LinkedIn post that breaks a rule?
- It is told at once. The usual case on LinkedIn is text over 3,000 characters: the post is kept as a draft and the tool result carries char_limit plus the fix, which Codex CLI applies with update_post.
- Where does the config go?
- In ~/.codex/config.toml, or .codex/config.toml in a trusted project. It is TOML, not JSON, which trips people who paste a snippet from another client. Once it loads, the LinkedIn tools are available in every session.
- Does the key have to be in the file?
- Not for the hosted server. bearer_token_env_var names a variable and Codex reads the key from your environment, so the file can be shared. The local form puts it under [mcp_servers.planpost.env]. Neither choice changes what you can post to LinkedIn.
Keep going
LinkedIn from other agents
Other networks from Codex CLI