Reddit is the single most-cited domain in AI answers. One analysis of over 150,000 LLM citations found Reddit accounted for 40.1% of cited sources — ahead of Wikipedia, YouTube, and Google's own results.

So of course every marketer on earth now wants to be on Reddit.

And of course Reddit noticed. The platform is now running its own LLMs to hunt brands planting fake conversations designed to get repeated back by ChatGPT.

That's the tension this guide sits in. I wanted to build a Reddit content generator that was actually useful — and the first thing I had to accept is that the obvious version of it is worthless.

The obvious version takes a topic and spits out a post. That post gets removed, or it sits at zero, or it gets you shadowbanned. I checked out a handful of the free tools in this category and most of them are exactly that: a thin wrapper that produces something with the shape of a Reddit post and the soul of a press release.

The version worth building is different. It's a drafting assistant that knows a specific subreddit's rules, has read how the regulars actually write, and hands you three angles to choose from — which you then edit, because you're the one whose name is on the account.

This guide walks through building that. I'll cover the rules you're designing around, the four components the agent needs, the full role prompt I landed on, and how to test it before you post anything.

What a Reddit Post Generator Actually Is

There are two very different products hiding under the same name.

The first is a mockup tool. You type text, it renders a fake Reddit post image for a slide deck or an ad. Useful, totally unrelated to what we're doing here.

The second is a drafting agent. You give it a subreddit, a thing you want to talk about, and some context about who you are. It gives you post drafts calibrated to that community.

This guide is about the second one. And within that, there's a further split that matters more than any feature:

Approach	What it does	What happens
Autopost bot	Generates and publishes on a schedule with no human in the loop	Removed by AutoMod, or eventually banned. Also likely violates Reddit's developer terms.
Drafting assistant	Generates 2-3 angles you read, edit, and post yourself	Cuts your drafting time by most of it, keeps a human accountable for what gets published

I'm going to be blunt: build the second one. Not because of some vague appeal to authenticity, but because the first one doesn't work anymore and carries real account risk. More on that below.

The Rules You're Building Around

Before writing a line of prompt, it's worth knowing the actual constraints. Most "Reddit automation" content skips this entirely, which is why so much of it is advice that would get you banned.

Reddit's API is expensive and gated

Since the 2023 pricing change, high-volume API access runs about $0.24 per 1,000 calls, and commercial use requires an actual contract with Reddit. The Developer Terms have been tightened repeatedly since.

The practical effect: a tool that continuously scrapes Reddit at scale is either expensive, unapproved, or both. GummySearch — one of the better-known Reddit research tools — shut down in late 2025 after failing to land a commercial agreement.

This is a bigger deal than it sounds, and it shapes the design. Your generator should not depend on live Reddit scraping. You feed it context manually, or from sources you're allowed to use. That's a constraint, but it's also freeing — it means you can build this on a normal no-code stack without an API contract.

Every subreddit sets its own gates

There is no sitewide karma floor. Each community configures AutoModerator however it likes. Roughly, what you're looking at:

Community type	Typical comment karma gate	Typical account age gate
Open / general	0	None
Hobby and niche subs	0-50	~7 days
Mid-size communities	50-200	~30 days
Large or strict subs	200-2,000	30-90 days

Comment karma is weighted more heavily than post karma in most AutoMod configs, because comment karma is evidence you actually participate. The two gates are checked independently — clearing one doesn't help if you fail the other.

No generator fixes this. If your account is three days old with two karma, the best post in the world gets auto-removed before a human sees it.

AI disclosure rules are spreading

Reddit's sitewide Content Policy doesn't categorically ban AI-generated text. It bans spam, deception, and coordinated inauthentic behavior — which is a different thing, and an important distinction.

The restrictions that bite are at the community level. A CHI 2025 study characterizing subreddit AI policies found the number of subreddits with explicit AI rules more than doubled in a single year, concentrated in larger communities and creative ones. Cornell researchers separately documented how AI content has become a compounding problem for volunteer moderators.

Subs like r/writing, r/ChangeMyView, and r/worldbuilding have hard bans or disclosure requirements. Others don't care at all.

This is exactly the kind of thing your agent should be checking for you — and it's the feature almost no generic tool has.

The 90/10 guideline still holds

The old community norm — roughly nine parts participation to one part self-promotion — remains the working standard across most subs. A generator that only writes your promotional posts will get you removed. One that helps you write genuinely useful comments too is a different proposition.

Why Most Reddit Content Generators Produce Slop

Merriam-Webster made "slop" its word of the year for a reason. And Reddit readers are unusually good at spotting it — the whole site is people arguing about whether things are real.

Here's what actually goes wrong with the tools I looked at.

They have no idea which subreddit you're posting to. A post that works in r/smallbusiness would be flamed in r/Entrepreneur and removed outright from r/marketing. Community fit is the entire game, and most tools treat the subreddit as a decorative dropdown.

They write in LLM house style. Em-dash-heavy, tidy three-part structures, "it's not just X, it's Y," a closing paragraph that summarizes what you just read. Reddit readers have developed a strong allergy to this. It reads as inauthentic even when the underlying point is good.

They have no specifics. Good Reddit posts are load-bearing on detail: real numbers, real timelines, the part where it went wrong. A generator with no access to your actual experience produces a post about the general shape of a topic, which is exactly the thing that gets zero upvotes.

They optimize for the post, not the thread. On Reddit, the comments are the content. A post that doesn't invite a reply is a dead post. Most generators end with a summary instead of a question.

Fixing these four things is basically the whole build.

What Your Generator Has to Know

Three inputs, and you need all three.

Rules — what the mods remove. The sidebar rules, the AutoMod behavior, whether self-promotion is allowed, whether AI disclosure is required, post flair requirements, title format requirements. This is a document you write once per subreddit and reuse forever.

Voice — how the regulars write. Not "casual and friendly." The actual texture: do top posts open with a one-line hook or three paragraphs of context? Do people use headers? How long is a typical top post? Are numbers expected? You get this by pasting in five or six real high-scoring posts as reference material.

Story — what only you can say. Your numbers, your mistake, your timeline, your specific client situation. This comes in at generation time, from you, every time. It's the input people skip, and skipping it is why the output is generic.

An agent with rules and voice but no story writes plausible nothing. An agent with story but no rules writes something good that gets removed. You need the set.

Building It: Step by Step

I built this on Pickaxe because the four things I need — instructions, a knowledge base, structured inputs, and a deployable interface — are in one place and none of it requires code. The same structure works anywhere you can set a system prompt and attach reference documents.

There's also a Reddit Post Generator template in the library if you want a running start rather than a blank page.

Step 1: Pick two or three subreddits, not twenty

This is the step people rush. A generator tuned to three communities you actually participate in will outperform one that nominally handles anything.

Pick subs where you'd be a credible poster — where you could answer a follow-up question without googling. Write them down. Everything else builds on this list.

Step 2: Build the rules document

For each subreddit, create a short document. Mine looks like this:

• Subreddit: r/example — 340k members
• Self-promotion: Allowed only in the Saturday thread. Links in post body = removed.
• AI policy: No explicit rule. Regulars are hostile to obvious AI writing.
• Title format: No clickbait. Questions do well. No all-caps.
• Flair: Required — one of Discussion / Question / Case Study.
• AutoMod gates: 30 days account age, 50 comment karma.
• What gets removed: Anything reading as a case study for your own product. Surveys. "What tools do you use" posts (asked daily).
• What does well: Specific failure stories with numbers. Long-form process breakdowns. Contrarian takes with evidence.

Ten minutes per subreddit, sitting in the sidebar and scrolling the top posts of the month. This document is the single highest-value thing in the whole build.

Step 3: Add voice samples to the knowledge base

Paste in five or six genuinely high-scoring posts from each target sub, as plain text. Label them with the score and the subreddit.

You're not asking the model to copy them. You're giving it a distribution to match — length, opening move, formatting density, how much hedging is normal.

If you're new to this part, our guide on adding a knowledge base to an AI agent covers how chunking and retrieval actually work under the hood, and why a handful of well-chosen documents beats a giant dump.

One warning: don't paste in posts from people you're trying to imitate stylistically to the point of impersonation. You're calibrating register, not cloning a person.

Step 4: Write the role prompt

This is where the four failure modes get closed off. Here's the prompt I settled on — copy it and swap in your own details:

You are a Reddit drafting assistant. You write DRAFTS for a human
to edit and post under their own account. You never claim a post is
ready to publish as-is.

## Your process, every time

1. Read the rules document for the target subreddit in your knowledge
   base. If the subreddit has no rules document, say so and stop —
   do not guess at the rules.
2. Check the user's story input. If they have given you no specific
   detail — no number, no timeline, no concrete situation — ask ONE
   question to get it before writing anything.
3. Draft THREE distinct angles on the same underlying material.
   Not three drafts of the same post. Three genuinely different
   entry points, for example: a failure story, a specific how-to,
   and a contrarian observation.
4. For each angle, give: two title options, the post body, and the
   suggested flair.
5. End with a RULE CHECK section listing each rule from the rules
   document and whether the draft complies.

## How to write

- Match the length and structure of the voice samples for that
  subreddit. If top posts there are 200 words, do not write 900.
- Open with the most specific concrete detail, not context.
- Use the user's real numbers and details. Never invent a statistic,
  a client, a result, or a timeline. If you need a number you do not
  have, write [NUMBER NEEDED] and move on.
- End the body with a real question that a reader could answer from
  experience. Not "what do you think?" — something specific.
- No em dashes. No "it's not just X, it's Y." No closing summary
  paragraph. No headers unless the voice samples use headers.
- Write at the reading level of a smart person typing quickly, not
  an editor. Contractions, sentence fragments, and a tangent are all
  fine.

## Hard rules

- If the subreddit's rules document says self-promotion is not
  allowed, do not include a link, a product name, or a description
  of the user's product. Not even subtly.
- If the subreddit requires AI disclosure, add the required
  disclosure line to every draft and flag it in the RULE CHECK.
- Never write anything presented as a first-hand experience the user
  did not tell you they had.

The details doing the heavy lifting: three angles instead of one (you pick, which makes you an editor rather than a rubber stamp), the [NUMBER NEEDED] rule (kills invented statistics), and the RULE CHECK section (turns compliance into visible output you can scan in five seconds).

If you want to go deeper on why prompts like this are structured the way they are, we wrote a full breakdown on prompt engineering for AI agents.

Step 5: Add structured inputs

Free-text-only is a mistake here. Give yourself fields, so you can't skip the story input:

• Target subreddit — dropdown of the two or three you set up
• What happened — the specific thing, with numbers
• What you want out of it — discussion, feedback, visibility, hiring
• Anything you cannot say — client names, unreleased details, numbers under NDA

That last field matters more than it looks. It's the difference between a tool you can use for client work and one you can't.

Step 6: Pick a model that writes like a person

This is genuinely a model-selection problem, not just a prompt problem. Some models have a much stronger pull toward tidy, structured, obviously-AI prose, and no amount of "write casually" fully overrides it.

Test the same prompt across a few. Pickaxe lets you switch models per agent without rebuilding anything, so it's a two-minute experiment — see the model comparison for what's available, and our writeup on mixing models across one workflow if you want different models handling drafting versus rule-checking.

My rough finding: the more capable reasoning models are better at the rule check, and slightly worse at sounding like a person typing. Splitting those two jobs across two models is a real improvement if you want to bother.

Testing It Before You Post Anything

Do not ship this straight to a live account. The failure mode is expensive — a removed post is nothing, a banned account is months of rebuilding.

Run these four tests:

The historical test. Feed it the details behind a post you already made that did well. Does it produce something in the same neighborhood? If its draft is obviously worse than what you wrote, your voice samples aren't doing their job.

The rules test. Give it a story that clearly violates one of the rules — a promotional angle in a no-promo sub. It should refuse, or strip the promotion and flag it. If it happily writes the violating post, your hard rules aren't hard enough.

The invention test. Give it a vague input with no numbers. It should ask you a question or emit [NUMBER NEEDED]. If it invents a plausible statistic, that's a serious problem — you'd have posted it.

The smell test. Read a draft out loud. If you wouldn't say it that way, the model is still in house style. Tighten the "how to write" section.

Our guide on testing and debugging AI agents before deploying goes further on building a repeatable test set rather than spot-checking.

The Step You Cannot Automate

You still have to read it, change it, and post it yourself.

This isn't a moral position, it's a practical one. The edit is where your actual knowledge enters the post — the aside the model couldn't know, the number it got slightly wrong, the sentence that sounds like you.

It's also the step that keeps you out of trouble. A human reading every post before it goes out is the difference between "using AI to write faster" and "running an inauthentic behavior campaign," and Reddit's enforcement increasingly turns on exactly that distinction.

In practice, the workflow costs about three minutes: generate, pick an angle, rewrite two sentences, post. Versus twenty-five minutes staring at an empty text box. That's the actual win — not volume, just a much lower activation energy for posting at all.

If you want the general framing on where to put the human checkpoint in an agent workflow, we covered it in human-in-the-loop AI agents.

Extending It

Once the core generator works, three additions are worth the effort.

A comment generator. Same rules document, different prompt: given a thread and your relevant experience, draft a genuinely helpful reply. This is the one that actually builds the karma you need, and it's where the 90/10 ratio gets satisfied. Honestly, if you only build one of the two, build this one.

A weekly idea digest. Rather than scraping Reddit, point a scheduled agent at your own material — support tickets, client calls, your notes — and have it surface three things worth posting about this week. Our guide on agents that run on a schedule covers the setup.

A rules refresher. Subreddit rules change whenever mods decide they do. Put a recurring reminder in your calendar to re-read the sidebars of your target subs and update the rules documents. Ten minutes a quarter.

If you're building a broader content operation rather than just Reddit, the same architecture generalizes — we walked through it in building an AI content factory.

Mistakes I'd Warn You About

Building for volume. Five posts a week across three subs is not a strategy, it's a ban timeline. The generator should make each post better, not make more posts.

Skipping the karma work. No prompt overcomes an account that AutoMod won't let through. Comment for two weeks before you post anything.

Letting it invent. The single worst outcome here is confidently posting a fabricated statistic to a community of specialists. The [NUMBER NEEDED] rule exists for this.

Using one generic prompt for every sub. If your prompt doesn't change between r/smallbusiness and r/devops, you've built the generic tool you were trying to avoid.

Posting the first draft. It's a draft. It says draft. Read it.

FAQ

Is using an AI Reddit content generator against the rules?

Reddit's sitewide Content Policy doesn't ban AI-assisted writing. It bans spam, deception, and coordinated inauthentic behavior. Individual subreddits may ban or require disclosure of AI content, and that's the level that matters — check the sidebar of every sub you post in, and build those rules into the agent.

Can I have it post automatically?

Technically possible, practically a bad idea, and depending on scale it runs into Reddit's Developer Terms. The value is in the drafting, not the publishing. Keep a person in the loop.

How much karma do I need before this is useful?

Depends entirely on your target subs. Small and niche communities often have no gate at all. Large ones commonly want 200-500 comment karma and 30+ days of account age. Build the comment generator first and the karma takes care of itself.

Will people be able to tell it's AI?

If you post the raw output, often yes — Reddit readers are unusually sensitized to LLM cadence. If you supply real specifics and edit the draft, no, because at that point the substance is yours and the model just saved you the blank-page problem.

Do I need the Reddit API for this?

No, and I'd argue you shouldn't design around it. You supply the context manually. That keeps you clear of the commercial API approval process and costs nothing.

Wrapping Up

The reason to build a Reddit content generator in 2026 isn't that Reddit is easy to game. It's that Reddit is hard to write for — the bar for specificity is high, the tolerance for marketing is near zero, and every community has its own unwritten register.

A generator that encodes those constraints turns a twenty-five minute task into a three minute one. A generator that ignores them produces things that get removed.

The difference is entirely in what you put into it: a rules document per subreddit, real voice samples, and your own specifics at generation time. The prompt is maybe 20% of it.

If you want to build this yourself, Pickaxe handles the instructions, knowledge base, inputs, and hosting in one place — and if you'd rather not start from scratch, clone the Reddit Post Generator template and swap in your own rules documents.