Post to Reddit from Codex

Codex can post to Reddit through Postiz. Install the Postiz skill or add the Postiz MCP server to Codex, connect your Reddit account in Postiz, then name the subreddit and what to post. Codex checks the available flairs, picks the post type, writes a title, and schedules one post or several across communities.

Setup Guide GitHub

Please make sure there is always a human in the loop.

Last updated: September 2026

How do I post to Reddit from Codex?

Set up Codex once with the Postiz skill or the Postiz MCP server, connect Reddit in Postiz, then ask. The whole setup takes a few minutes.

Setup, then just ask

# One-time setup, option A: Postiz skill + CLI
npx skills add gitroomhq/postiz-agent
export POSTIZ_API_KEY=your_api_key   # or: postiz auth:login

# One-time setup, option B: Postiz MCP server (OAuth, no key)
codex mcp add postiz --url https://mcp.postiz.com/mcp-oauth-dynamic
codex mcp login postiz

# Then just ask Codex:
> Post our tutorial to r/programming
  with the "Tutorial" flair, tomorrow at 9am

Codex: Done! Your Reddit post is scheduled.

Reddit-Specific Features

🎯

Subreddit Targeting

Post to one or multiple subreddits simultaneously. Target the exact communities where your content belongs.

📝

Post Types

Create self posts, link posts, image posts, or video posts. Each type is optimized for Reddit's native rendering.

🏷

Flair Support

Automatically discover and apply required flairs for each subreddit. Never have a post rejected for missing flair again.

🔄

Cross-Posting

Share content across multiple subreddits in a single request. Each subreddit gets its own title and flair configuration.

🔗

Link & Media Posts

Share URLs, images, or videos directly. Link posts drive traffic while media posts maximize engagement within Reddit.

📅

Scheduled Posting

Schedule Reddit posts for peak activity times. Hit the front page by posting when your target subreddits are most active.

How does Codex post to Reddit?

You describe what you want in plain language and Codex handles the Postiz calls for you. Here is how a typical conversation goes.

Find Your Reddit Integration

Ask Codex whether your Reddit account is connected. It can also look up available flairs for any subreddit before posting.

Example conversation

> Is my Reddit account connected to Postiz?

Codex: Yes — your Reddit account is connected
  and ready. Want me to post something?

Choose Your Post Type

Reddit supports multiple post types. Self posts contain text, link posts share URLs, and image/video posts upload media directly. Pick the right type for your content.

Example conversation

> Draft a Reddit post about our new
  feature launch

Codex: Here's a draft for Reddit:
  "We just shipped something big..."
  Want me to add media and schedule it?

Create Your Post

Schedule a Reddit post with your content, target subreddit, post type, and flair. You can post to multiple subreddits at once by adding more items to the subreddit array.

Example conversation

> Yes — add screenshot.png and schedule
  it for tomorrow at 9am

Codex: Done! Scheduled on Reddit for
  tomorrow at 9:00 AM.

Reddit Settings Reference

Mention any of these in plain language and Codex sets them for you. These are the Reddit options it can apply to any post.

Field	Type	Required	Description
`__type`	string	Yes	Must be "reddit"
`subreddit`	array	Yes	Array of subreddit targets: [{value: {subreddit, title, type, url?, is_flair_required, flair?}}]
`subreddit[].value.subreddit`	string	Yes	Name of the subreddit to post to (without r/ prefix)
`subreddit[].value.title`	string	Yes	Title of the Reddit post
`subreddit[].value.type`	string	Yes	Post type: "self", "link", "image", or "video"
`subreddit[].value.url`	string	No	URL for link-type posts
`subreddit[].value.is_flair_required`	boolean	Yes	Whether the subreddit requires a flair
`subreddit[].value.flair`	object	No	Flair object with id and name (required if is_flair_required is true)
`subreddit[].value.flair.id`	string	No	Flair template ID from the subreddit
`subreddit[].value.flair.name`	string	No	Display name of the flair

Common Configurations

Ask Codex for any of these common Reddit scenarios and it applies the matching settings.

Simple Self Post

Just ask

> Post it with: Simple Self Post

Codex: Got it. Applying:
  subreddit: {'subreddit': 'programming', 'title': 'Check out this new AI scheduling tool', 'type': 'self', 'is_flair_required': False}

Link Post with Flair

Just ask

> Post it with: Link Post with Flair

Codex: Got it. Applying:
  subreddit: {'subreddit': 'webdev', 'title': 'How we built our scheduling engine', 'type': 'link', 'url': 'https://example.com/blog/scheduling-engine', 'is_flair_required': True, 'flair': {'id': 'abc123', 'name': 'Article'}}

Cross-Post to Multiple Subreddits

Just ask

> Post it with: Cross-Post to Multiple Subreddits

Codex: Got it. Applying:
  subreddit: {'subreddit': 'programming', 'title': 'New AI social media scheduler', 'type': 'self', 'is_flair_required': False}, {'subreddit': 'artificial', 'title': 'We just launched our AI social media scheduler', 'type': 'link', 'url': 'https://example.com/launch', 'is_flair_required': False}

Image Post

Just ask

> Post it with: Image Post

Codex: Got it. Applying:
  subreddit: {'subreddit': 'dataisbeautiful', 'title': 'Social media engagement trends 2025', 'type': 'image', 'is_flair_required': True, 'flair': {'id': 'def456', 'name': 'OC'}}

What is Codex?

Codex is OpenAI's coding agent. It runs as the Codex CLI in your terminal (npm install -g @openai/codex), as an IDE extension, and in the cloud, and it can run shell commands and call MCP servers, which is how it drives Postiz. Codex is not ChatGPT: ChatGPT is the chat assistant on chatgpt.com and connects to Postiz differently (see the ChatGPT guide). For the full setup, start at the Codex + Postiz hub.

💻

Terminal & IDE Native

Codex runs in your terminal or IDE. You type what you want in plain English and it handles Postiz for you — no extra configuration needed.

🔧

Autonomous Execution

Codex runs commands inside a sandbox with approval rules you control, and works through multi-step tasks like discovering channels, uploading media, and scheduling Reddit posts.

⚡

Parallel Tasks

Run multiple Codex tasks simultaneously. Schedule posts to different platforms in parallel while Codex handles other coding work.

How Postiz Works with Codex

Codex discovers Postiz two ways: the postiz skill, which it loads from .agents/skills or ~/.agents/skills and which you can invoke with $postiz, or the Postiz MCP server added with codex mcp add. Either way it learns the available tools and chains them for Reddit workflows.

✓Install the Postiz skill with npx skills add, or add the Postiz MCP server with codex mcp add
✓Codex loads skills from .agents/skills and reads SKILL.md to learn the Postiz CLI
✓Authenticate with POSTIZ_API_KEY or postiz auth:login; the MCP route uses OAuth instead
✓Codex runs commands in its sandbox and asks for approval based on your permission settings
✓Works alongside your coding tasks in parallel

Install Postiz

# Install the Postiz skill
npx skills add gitroomhq/postiz-agent

# Set your API key
export POSTIZ_API_KEY=your_api_key

# Or add the Postiz MCP server instead (OAuth, no API key)
codex mcp add postiz --url https://mcp.postiz.com/mcp-oauth-dynamic
codex mcp login postiz

# Then ask, interactively or headless
codex "list my social media integrations"
codex exec "post today's changelog to Reddit"

Reddit Posting with Codex

Tell Codex what to post from your terminal or IDE — it discovers your integrations via Postiz and handles the entire publishing workflow.

💻

Just Ask Codex

Terminal and IDE integration

Tell Codex what to post from your terminal or IDE — it discovers your integrations via Postiz and handles the entire publishing workflow.

Codex CLI

$ codex "Post to Reddit about our
  new feature launch, schedule for
  tomorrow at 9am"

Codex: I'll handle that.
  Found your Reddit integration.
  Composing and scheduling the post.

  Done! Your post is scheduled.
  Post ID: abc-123

💻

Parallel Tasks

Multiple tasks at once

Codex can handle multiple tasks in parallel. Schedule posts to different platforms while it works on other coding tasks simultaneously.

Codex Parallel Tasks

# Run multiple posting tasks in parallel
$ codex "Schedule a post about our
  launch to X for tomorrow 9am" &

$ codex "Write a LinkedIn article
  about our new feature and schedule
  for tomorrow noon" &

$ codex "Fix the bug in auth.ts"

# All three tasks run simultaneously

Why Codex + Postiz for Reddit

Codex's autonomous execution makes Postiz a natural fit. The agent reads the SKILL.md to understand every available command, then autonomously chains them together for Reddit workflows.

✓Runs in your terminal or IDE — just type what you want
✓Autonomous execution in sandboxed environments
✓Parallel task support — post while coding
✓Reads SKILL.md for automatic command discovery
✓Cross-post to Reddit + other platforms in a single session
✓Powered by OpenAI's most capable models

SKILL.md (loaded by Codex from .agents/skills)

---
name: postiz
description: Social media automation
  CLI for scheduling posts across
  30+ platforms including Reddit
homepage: https://docs.postiz.com/public-api/introduction
---

# Loaded by Codex from .agents/skills
# Invoke explicitly with $postiz

# Available Commands
- postiz integrations:list
- postiz integrations:settings <id>
- postiz integrations:trigger <id>
    getFlairs -d '{"subreddit":"..."}'
- postiz posts:create
- postiz upload <file>
- postiz analytics:platform <id>

# Reddit Settings
subreddit (array of targets),
type (self/link/image/video),
title, url, flair, is_flair_required

Also Works with Claude Code

Postiz works with any AI agent that can run commands or call MCP tools — you ask, the agent does the work. That includes Anthropic's Claude Code: see the Claude Code Reddit guide, or the Postiz Agent page for any other agent.

Claude Code

by Anthropic

Claude reads the Postiz skill so it knows what it can do, then autonomously discovers your Reddit integration, checks flair requirements, and schedules posts to the right subreddits.

Claude Code

> Post to r/programming and r/webdev
  about our new feature, schedule for
  tomorrow morning

Claude: Done! Scheduled on Reddit for
  tomorrow at 9:00 AM.

Can Codex post to Reddit and other platforms at once?

Schedule the same content to Reddit and other platforms in a single request. Each platform gets its own settings.

Example

> Post "Excited to announce our new feature!" to
  Reddit and LinkedIn tomorrow at 9am, then schedule
  a daily tip on Reddit every weekday at 10am

Codex: Done! Scheduled:
  - Reddit + LinkedIn: tomorrow 9:00 AM
  - Daily tips on Reddit: Mon-Fri 10:00 AM

What can I ask Codex to post on Reddit?

Codex takes plain-English prompts in an interactive session, as a one-off codex exec command, or through the $postiz skill. These are the kinds of prompts people type for Reddit.

Prompts for Reddit

> Post our tutorial to r/programming with the "Tutorial" flair
  tomorrow 9am, text post, body from ./posts/tutorial.md

$ codex exec "Share https://example.com/launch to r/SaaS and
  r/artificial as link posts titled 'We built an AI social scheduler'"

> $postiz What flairs does r/webdev require? Then post the
  release notes there with the right flair

What Reddit rules should Codex follow?

These are the Reddit limits and required settings Postiz enforces. Codex reads them from postiz integrations:settings, and you can mention any of them in your prompt.

✓Reddit titles are limited to 300 characters, and every post needs a title.
✓Each subreddit target needs a type: self (text), link, image, or video.
✓When is_flair_required is true, Codex must pick a flair id from postiz integrations:settings or Reddit rejects the post.
✓Subreddit names go without the r/ prefix; each target can have its own title, type, and flair.
✓Codex cannot bypass subreddit rules or moderation; check self-promotion policies before scheduling.

Codex and Reddit FAQ

How do I post to Reddit from Codex?

Install the Postiz skill with npx skills add gitroomhq/postiz-agent, or add the Postiz MCP server with codex mcp add postiz --url https://mcp.postiz.com/mcp-oauth-dynamic. Connect Reddit in Postiz once, then ask Codex in plain English what to post and when. Codex resolves the Reddit settings, uploads any media, and schedules the post.

How does Codex know which flair a subreddit requires?

It asks Postiz. Running postiz integrations:settings for your Reddit channel returns each subreddit's flair list and whether a flair is required. Codex picks the matching flair id and name, or asks you to choose if the names are ambiguous. If is_flair_required is true and no flair is set, Reddit rejects the post.

Can Codex post the same content to several subreddits at once?

Yes. The Reddit settings accept an array of subreddit targets, each with its own title, post type, optional URL, and flair. Say "post this to r/programming and r/webdev" and Codex builds one entry per community. Use different titles per subreddit when their rules differ; Codex can adapt each one.

Can Codex post to Reddit on a schedule without me watching?

Yes. Postiz stores scheduled Reddit posts and publishes them at the chosen time, so Codex does not need to stay open. For unattended runs, call codex exec with your prompt from a script or cron job. Keep a human reviewing the output, since Codex will publish exactly what it is told to publish.

Do I need a Postiz API key to post to Reddit from Codex?

Not with the MCP route. Run codex mcp login postiz and Codex signs in to your Postiz account over OAuth, so it only reaches channels you already connected, including Reddit. The CLI skill route needs either postiz auth:login or a POSTIZ_API_KEY environment variable. Your Reddit login itself never leaves Postiz.

Is posting to Reddit from Codex the same as posting from ChatGPT?

No. Codex is OpenAI's coding agent for your terminal and IDE, and it reaches Postiz through the Postiz skill or MCP server. ChatGPT is the chat assistant on chatgpt.com, which connects to Postiz as an app or custom MCP connector. Both can publish to Reddit; see the ChatGPT guide for that setup.