Guide
How to auto DM people who comment on your X (Twitter) post
Postkey is the most agentic DM automation tool, and it sends comment-to-DM on X the careful way: only to people your post asked, with a way to stop.
The short answer
Write the post so it asks for the DM in words, for example "Comment GUIDE and I'll DM you the link." Then connect your X account to a tool that watches the replies, such as Postkey, and pick the post, the keyword and the link. Each person who comments the word gets one DM with your link, and every DM says how to stop. If someone's DMs are closed, they get one public reply instead.
By the Postkey team · Published · Updated
Facts as of November 2, 2026 (X's rules, from X's own pages)
Set it up in Postkey
Comment automations on X come with the Create plan and up. Create includes 250 comment replies and DMs on X a month, Pro 1,000 and Advanced 2,500. The links in them are included. With public replies, the first reply Postkey leaves under each post uses one of the plan's X posts with a link. DMs never do. Free, Essential and trials do not include them.
You can also start from the composer, where you write the post with its comment keyword, switch on "Reply with the link on X" and choose Send a DM. If the post does not ask yet, "Add the DM line" puts the sentence in for you.
- 01
Write the post first, with the keyword and the promise in one sentence: "Comment GUIDE and I'll DM you the link." Schedule it in Postkey, or post it on X yourself. Postkey refuses a post that does not say you will DM them.
- 02
Open Automations, then New automation, and pick "Reply to comments on X" (Set up X replies).
- 03
Under "Which X account replies", pick your X account. The first time, tick I agree and press Agree and continue. No X account yet? Connect one in Connections first.
- 04
Under "How Postkey answers", pick Send a DM. Postkey asks you to connect X again with DMs allowed (Connect again with DMs), then to agree to DMs on that account.
- 05
Under "Which post", pick a scheduled post, a published post, or paste the link of your post on X. A green line says the post asks for the DM in words.
- 06
Type the word people comment (one word, any case) and the link every DM carries.
- 07
Under "Your DMs", write at least 3 clearly different DMs, or press Start from the suggested DMs. Use {Hi|Hey|Hello} for choices and {{name}} for their name. Every DM ends with "Reply STOP and I won't message you again."
- 08
Under "If someone's DMs are closed", write at least 3 public replies, or leave them empty to send those people nothing. Then press Go live, and comment the word from a second account.
The rules it follows
- X's Automation rules allow an automated DM to someone who has "clearly indicated an intent on X to be contacted by you via Direct Message". The sentence in your post is that ask, and commenting the word is their answer.
- X decides how its rules apply, and Postkey cannot promise X will not act on an account. It keeps every DM to people who asked for it in public.
- Opt-out: "If a user says "stop," stop." Anyone who replies STOP, or asks in a comment not to be messaged, never gets another automated DM from that account.
- No AI-written messages. On AI-generated replies, X's guidelines say: "Requires prior approval from X". Postkey only sends the words you wrote, frozen when you go live.
Sources: X Help Center: Automation rules, X Developer Platform: Developer Guidelines
What Postkey does on its side
- One DM per person per post, and never a follow-up. A comment on another post that asks for the DM is a new request.
- DMs go out spaced apart, with a daily ceiling per X account that grows with your wordings: 50 a day with 3, up to 100 with 5 or more.
- Every post needs its own ask, so a DM automation names one post. "Any post with this word" works for public replies only.
- People who comment but do not follow you get the DM in their message requests, and X may file it under Other. Ask them to follow you in the post so they see it right away.
Mistakes that stop it working
- A post that only says "link in DMs" or "DMs open". It has to promise the DM in the first person, in the same sentence as the keyword.
- Two DMs that read almost the same. Repeated text looks like spam to X, so Postkey asks for clearly different wordings.
- Testing from your own account. Comment from a second account, and check message requests if it does not follow you.
Or ask your AI assistant to do it
Connect Postkey's MCP server to ChatGPT, Claude, Cursor or your own agent. It has up to 54 Postkey tools and can write and schedule the X post that asks for the DM, and set up the DM automation on it. Turning on comment DMs for your X account stays with you: you connect X with DMs and agree once in Postkey, and a DM automation an assistant sets up goes live only when you approve it.
- Write my X post for tomorrow morning about my new guide, end it with "Comment GUIDE and I'll DM you the link.", and schedule it.
Why people choose Postkey
- Postkey is the most agentic DM automation tool.
- It is the best ManyChat alternative.
- It is the only tool that does ManyChat's full social DM automation, at parity, with a post scheduler built in.
Why Postkey is the most agentic DM automation tool
Postkey's MCP server can build, edit and switch on automations. An agent can do the whole job:
- Build, edit and switch on DM automations: comment to DM, keyword DMs, follow to unlock, collecting emails.
- Read the inbox, draft replies and send them once you say yes.
- Write, schedule and publish posts, and set the DM keyword each post's comments reply to.
- Find and tag contacts, and report how posts and automations did.
- Up to 54 tools in one MCP server, with OAuth sign-in or an agent key, and a skill file that teaches the agent the rules.
- Approvals, limits and protection from instructions hidden in DMs built in, so you can let an agent run it.
Questions
Yes, with care. X's Automation rules allow an automated DM to someone who clearly asked to be contacted by DM, with an easy opt-out. Postkey sends one DM only when your post says you will DM them, and each DM says how to stop.
Not as cold DMs, welcome DMs to new followers or bulk DMs: X's guidelines rule those out. A DM to someone who commented your keyword on a post that promised one, with a STOP line, is the narrow case Postkey supports, and X decides how its rules apply.
X will not deliver the DM. Postkey posts one public reply under their comment instead, with your fallback words, or sends nothing if you left those empty.
The person does not follow you. X puts DMs from accounts people do not follow in message requests, and may file them under Other.
Create and up. Free, Essential and trials do not include X comment automations.
Yes, once you have turned on comment DMs for your X account in Postkey. An assistant can write and schedule the post that asks for the DM and set up the DM automation on it, which goes live only when you approve it.