The short answer
When someone comments a keyword on your post, Instagram can notify your app through a webhook, and your app can send that person a DM. It is an official, permitted flow — because the comment counts as the person starting the conversation. It is not cold outreach and must not be used as such.
Step by step
1Set the keyword and the reply
Pick a word people can type without thinking — LINK, GUIDE, PRICE. Write the DM you want sent. Keep it short and deliver what you promised in the post immediately; a DM that asks another question loses most people.
2Optionally reply publicly too
A short public reply under the comment ('sent!') does two things: it tells the commenter to check their requests folder, and it shows everyone else that the offer works.
3Say the keyword in the post itself
The mechanism only works if people know about it. Put the instruction in the caption and say it out loud in the Reel.
4Check the requests folder
DMs from accounts that do not follow you land in Requests, not the main inbox. Tell people that in the reply or half of them never see the message.
What catches people out
- Instagram only permits DMs inside a messaging window opened by the person contacting you. Automation that messages people who did not interact first is against policy and puts the account at risk.
- Sending the same DM twice for the same comment is a fast way to look like spam. A correct implementation deduplicates per comment.
- The automation must never reply to your own comments, or two accounts you own can trigger each other in a loop.
- Accounts that hold a role on the app itself (developer, tester) do not generate comment webhooks. If you are testing, comment from an unrelated account or you will conclude it is broken when it is not.
Related guides
Last checked 2026-09-01. Instagram changes its API without notice — if something here is wrong, tell us and we will fix it.
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