> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dmly.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Automate comments and comment-to-DM
> Reply to comments automatically, DM commenters privately, and hide or delete unwanted comments on Facebook, Instagram and TikTok.
Comment automation watches the comments under your posts and acts on them: a public reply,
a private DM to the commenter, a like, a hide, or a delete. It runs on three channels —
Facebook Pages, Instagram and TikTok — through four triggers in the flow builder:
| Trigger | Channel | Fires when |
| ------------------------- | --------- | ------------------------------------ |
| **Facebook comments** | Facebook | "User comments on your Post" |
| **Post or Reel comments** | Instagram | "User comments on your Post or Reel" |
| **Live comments** | Instagram | "User comments on your Live" |
| **Video comments** | TikTok | "User comments on your video" |
On Instagram the two triggers are interchangeable today: every Instagram comment — feed,
Reel or Live — fires automations built on *either* trigger. Pick whichever reads better;
don't build one automation on each expecting them to split the traffic, because both
will fire on the same comments.
A few things are true for every comment trigger:
* **Only brand-new comments fire it.** Edited comments and deleted comments do nothing, and
your own Page's or account's comments never trigger your own automations. Replies *under*
a comment count as comments too — someone answering another commenter can trigger your flow.
* **Every commenter becomes a Contact.** DMLY creates (or matches) a
[contact](/contacts/overview) for the commenter, named from their username. On Facebook and
Instagram, comments and DMs from the same person belong to the same contact but thread
separately in the [Inbox](/inbox/overview) — you'll see a comment thread alongside their DM
conversation. On TikTok, a commenter and a DMer are separate contacts (TikTok's API keeps
the two identities apart).
* **The comment thread is a real Inbox thread.** Your automated public replies appear there
as your Page's own comments, and your team can answer manually with **Write a public
reply…** in the composer.
The trigger's **Which posts?** setting offers **All posts** and **Specific** with a post
picker — but the **Specific** selection is not enforced today. An automation saved with
specific posts still fires on comments on *every* post on the account. Until this changes,
scope your automation with keywords, not posts — and be especially careful combining a
no-keyword trigger with **Delete Comment**, which would permanently delete matching
comments across all your posts.
## Reply to comments automatically
The simplest comment automation: when someone comments, post a public reply under their
comment.
Create a new automation on your Facebook, Instagram or TikTok channel in the
[flow builder](/automation/flow-builder) and pick the comment trigger for that channel —
for example **Post or Reel comments** on Instagram.
On the trigger, choose how the comment text is matched:
* **Any message (no keyword filter)** — fire on every comment
* **Message contains a keyword**
* **Message is an exact match**
* **Message starts with a keyword**
Matching is case-insensitive, so `Price`, `PRICE` and `price` all match. Leave the
keyword list empty and the automation fires on any comment.
The trigger also has **Only respond once per contact** — turn it on for giveaway-style
automations where each person should only ever get one response, however many times
they comment.
Comment-triggered flows get an extra palette group, **Comment actions**, with four
steps: **Reply to Comment**, **Like Comment**, **Hide Comment** and **Delete Comment**.
(The group only appears when the flow starts from a comment trigger — these steps need
a comment to act on.)
Drag in **Reply to Comment** and write the **Public reply**. It supports contact tokens —
`{{first_name}}` and the rest — but remember a fresh commenter's name is seeded from
their username, so `{{first_name}}` may resolve to a handle rather than a real first
name. The default text is "Thanks for your comment! 🙌 Check your DMs." — change it if
you're not also sending a DM.
If the reply is empty, the builder flags the step with an amber "Public reply text is
empty." warning. Heed it — the flow will still publish, and the empty reply only fails
when it runs.
[Publish the flow](/automation/publishing-bots), then comment on one of your posts
**from a different account** — your own Page's comments never trigger it. The public
reply appears under the comment, and in the Inbox the comment thread shows the reply as
your own comment.
## Comment-to-DM
The classic pattern: "Comment WANT and I'll DM you the link." This works on **Facebook and
Instagram** — a comment lets you open a DM with someone who has never messaged you.
Same as above: a **Facebook comments** or **Post or Reel comments** trigger, matching
mode **Message contains a keyword** (or **exact match** for a cleaner giveaway), keyword
`WANT` or whatever you announce in the caption.
Add **Reply to Comment** with something like "Check your DMs!". It isn't required for
the DM to work, but it tells everyone else scrolling the comments that the mechanic is
real — which is half the point of the pattern.
Add a **Send Message** step with the link or content you promised. In a comment-triggered
flow, the **first text message** of the run is delivered as a *private reply* to the
comment — a special Meta mechanism that opens the DM thread even though the commenter
has never messaged you, outside the normal 24-hour messaging window.
[Publish](/automation/publishing-bots), announce the keyword in your post caption, and
watch the comment thread and DM land per commenter in the Inbox.
The private reply has hard limits worth designing around:
* **One per comment.** Only the first message of the run uses it. Each new comment is
processed exactly once, so there is no way to get a second private reply out of the same
comment.
* **Text only.** The private reply carries plain text — no images, cards or buttons. If the
first message step in your flow is an image or a card, it skips the private-reply
mechanism entirely and is sent as a normal DM instead, which may not reach a commenter
who has never messaged you. **Make the first message a text message** containing what
matters (the link), and put media after it.
* **Later messages are ordinary DMs.** A comment opens a 24-hour messaging window, so
follow-up steps in the same flow are attempted normally — but their delivery is decided
by Meta at send time, and a rejection shows up in [Logs](/troubleshooting/logs). Front-load
the message that matters.
Not possible. TikTok has no comment-to-DM mechanism: a **Send a DM** step in a
**Video comments** flow can only deliver to someone who already has an open DM
conversation with you (within TikTok's 48-hour window) — for a pure commenter it fails.
TikTok also keeps commenters and DMers as separate contacts, so there is no thread to
open.
What works instead: put the payoff in the **Reply to Comment** step. The public reply is
the only reliable way to answer a TikTok commenter, so use it to point people at your
bio link or ask them to message you first.
## Moderate comments automatically
Keyword-triggered hide and delete keeps spam and abuse off your posts without a human
watching the comments.
Create a comment-triggered flow with **Message contains a keyword** and list the terms
you moderate — competitor links, slurs, crypto spam phrases. Keep the list specific:
matching is a substring check, so a short keyword like `win` also matches "winter".
They are genuinely different:
* **Hide Comment** — "Hides the comment from everyone except its author." The commenter
still sees their own comment and doesn't know it was hidden; everyone else stops
seeing it. Good for spam and negativity, because it doesn't provoke a reaction.
Facebook and Instagram only — on TikTok this step is skipped with a note in the
thread ("Hiding comments isn't supported on TikTok — skipped."), because TikTok has
no hide.
* **Delete Comment** — "Permanently deletes the comment. Use sparingly — this can't be
undone." Works on all three platforms. The commenter can see it's gone.
There is no un-hide, un-like or restore step in a flow — hide is reversed manually on
the platform, delete not at all.
Each moderated comment leaves a quiet system note in its Inbox comment thread — "Hid
the comment" or "Deleted the comment" — so your team can see what the automation did
and to whom.
## Message the commenter after moderating
You can chain moderation with a DM — hide or delete the comment, *then* privately tell the
person why: "We removed your comment because it broke our rules; here's how to reach us."
This works on Facebook and Instagram, because every comment step lets the flow continue —
a hide or delete (even a failed one) never stops the run, and the private-reply DM still
targets the original comment. Order matters, though:
* **Hide, then Send Message** — the safe chain. The comment still exists (hidden), so the
private reply lands normally.
* **Delete, then Send Message** — risky. A private reply to a comment that no longer exists
isn't something DMLY guards against, and Meta may reject it. If you want to delete *and*
notify, put the **Send Message** step **before** the **Delete Comment** step: the DM is
delivered first, then the comment is removed. Nothing in the builder enforces this
ordering — it's on you.
On TikTok the notify half isn't possible at all (no comment-to-DM, see above): you can
delete the comment, but you cannot message the commenter about it.
## What works where
| | Facebook | Instagram | TikTok |
| --------------------------------------- | --------------------- | -------------------------------------------- | ---------------------- |
| Trigger | **Facebook comments** | **Post or Reel comments**, **Live comments** | **Video comments** |
| **Reply to Comment** (public) | Yes | Yes | Yes |
| **Like Comment** | Yes | Yes | Yes |
| DM the commenter (private reply) | Yes | Yes | No |
| **Hide Comment** | Yes | Yes | No — step is skipped |
| **Delete Comment** | Yes | Yes | Yes |
| Commenter and DMer are the same contact | Yes | Yes | No — separate contacts |
The quick builder has the same triggers and equivalent actions — **Reply to comment**,
**Send a DM**, **Like the comment**, **Hide the comment**, **Delete the comment** — with
one difference in keyword matching: a flat comma-separated list, always
contains-matching, no match-mode choice ("Comma-separated. Leave empty to trigger on any
comment."). The DM action uses the same one-private-reply-per-comment mechanism.
If both a published flow and a quick automation match the same comment, **the flow wins**
and the quick automation does not fire. The quick builder also shows **Conditions** such
as **Comment / message text** and **First-time contact** — these are saved but not
applied while the automation runs as a quick automation; they only take effect after you
convert it with **Edit in Flow Builder**. Prefer the flow builder for anything beyond a
single canned reply.
## Troubleshooting
A failed reply, like, hide or delete does two things: it writes a system note in the
comment thread ("... failed — see Logs.") and records an error row in
[Logs](/troubleshooting/logs) under the **Errors** status, with the comment id and the
error Meta or TikTok returned. The flow itself keeps going — a failed comment action
never cancels the rest of the run, so a failed hide doesn't stop the DM step after it.
The usual suspects, in order of likelihood:
* You tested with **your own account** — the Page's or business account's own comments
are always ignored.
* You **edited** an existing comment — only brand-new comments fire the trigger.
* The bot is **paused for that contact** (a teammate took over the conversation).
* **Only respond once per contact** is on and that person already triggered it once.
* A previous run for that contact is **still active** on the same automation — a repeat
comment during an active run is suppressed.
* You expected **Specific posts** to include the post — post targeting is not enforced;
check the keywords instead.
The full checklist is at
[Automation not triggering](/troubleshooting/automation-not-triggering).
Check the first message step in the flow: if it's an image or a card, the private-reply
mechanism is skipped and the send goes out as a normal DM, which can fail for someone
who has never messaged you. Make the first step a plain text message. If it *is* text,
look for a send failure in [Logs](/troubleshooting/logs) → **Errors**. And on TikTok,
the DM step cannot reach a commenter at all — see the table above.
Every trigger, including the four comment triggers.
The canvas, nodes and ports in full.
Drafts, versions and the activation checks.
Where every send and comment action is recorded.