Post to Listmonk from Codex

Codex drafts it. You approve it. PostDelegate posts it.Listmonk: Email campaigns through your own Listmonk.

How to post to Listmonk from Codex

Add PostDelegate to Codex. Add the server to ~/.codex/config.toml as below. Run codex mcp login postdelegate and sign in in your browser.
~/.codex/config.toml
```
[mcp_servers.postdelegate]
url = "https://app.postdelegate.com/mcp-oauth-dynamic"
```
Connect Listmonk in PostDelegate. You need a running Listmonk reachable from the internet over http:// or https://, and a Listmonk username and password that can read settings and lists and create campaigns.
Ask Codex for a draft. Describe the post in plain words. Codex checks your Listmonk channel's rules, creates the post and sends back a preview link.

Teach Codex the posting rules

Add PostDelegate’s AGENTS.md to your repository, so Codex knows the MCP tools, the REST API and the safety rules when it works there. Agent files has the steps.

What to ask Codex

Mention any Listmonk setting in plain words and Codex fills it in. Codex can also read text files in your project, such as a changelog or a draft in Markdown.

Draft a Listmonk campaign for the newsletter list, subject “November update”, with a preview line.
Schedule the campaign for Tuesday at 7:00 with the Default template.
Write this month’s newsletter from CHANGELOG.md and docs/roadmap.md, as a draft campaign.

What Codex can do on your Listmonk channel

Check the rules first. Before writing, it reads your Listmonk channel's length limit and required settings.
Draft, schedule or post. It creates a draft, a scheduled post or an immediate post, and runs the same checks as the app.
Use your media. It attaches files from your media library or adds one from a public link.
Review and fix. It lists what is scheduled, changes the Listmonk settings of a post that has not gone out, and deletes posts you no longer want.

Listmonk is newsletter software you host yourself. Connecting it lets PostDelegate create a campaign in your Listmonk and start it on a schedule, so a newsletter can sit on the same calendar as the social posts that announce it.

Listmonk settings Codex can fill in

Setting	Notes
Subject	Required. The email subject.
Preview	The preview text shown next to the subject in many inboxes.
List	Required. Choose from the lists in your Listmonk.
Template	Optional. Choose a Listmonk template, or Default.

Before you start

Publishing starts the campaign. When the post goes out, PostDelegate creates a regular campaign on your chosen list and sets it to running, which sends it.
Use a PostDelegate draft to hold a campaign back, and send a test through Listmonk itself first.

The Listmonk channel guide has every field, and MCP tools lists exactly what an assistant can and cannot do.

Questions

Will Codex publish to Listmonk without asking me?

Not unless you ask it to. Ask for a draft and the post waits on your calendar until you schedule it, and your workspace's approvals apply as usual. Tools that change data are marked as such, so Codex can ask you before it schedules or deletes anything.

Do I need an API key to connect Codex?

No. Codex signs in with your PostDelegate account through your browser. An API key is only for clients that cannot sign in, as described in MCP clients.

Does it cost extra to use Codex with PostDelegate?

No. The MCP server is on every plan, and Codex runs on your own Codex account, so PostDelegate never charges for AI. Every plan starts with a 7-day free trial with no card.

Can Codex attach images or video to a Listmonk post?

It can use files already in your media library, or add one from a public link. It cannot fetch files from your computer, so upload those in the app first. See MCP tools.

Does PostDelegate send the email itself?

No. PostDelegate creates a regular campaign in your own Listmonk and sets it to running, and your Listmonk sends it. Use a draft in PostDelegate to hold a campaign back, and send a test through Listmonk first.

Can I attach files to a Listmonk campaign?

No. Attachments are not sent. Put pictures inside the HTML content where they should appear, using images from the media library.

Listmonk from other assistants

Other networks from Codex

Prefer to plan Listmonk posts yourself? See the Listmonk scheduler.