A WhatsApp bot that can still write on day three
Interactive buttons, files up to 100 MB and an AI agent that answers in your voice — plus the one thing every other network refuses: a way back in after the 24-hour window shuts.
Start free for 7 daysAlmost everything written about building a WhatsApp bot skips the rule that decides whether it works: Meta only lets a business message someone freely for 24 hours after that person last wrote. Miss it and your carefully built flow has nowhere to go. This is not a limit any tool can engineer around — it is the platform, and it applies to us exactly as it applies to everyone else.
What differs is what happens when the window closes. On Instagram and Messenger, that is the end of the conversation until the person writes again. WhatsApp is the exception: with a template Meta has approved in advance, you can open a new one. It is the only network in Ignix where that is true, and it is the reason a WhatsApp bot behaves less like a reply machine and more like a channel you can actually plan around.
The rest of this page is what the bot can send and what it refuses, taken from the same capability table the composer and the flow builder enforce.
What a WhatsApp message can actually carry
These are the real limits, not marketing rounding. Each one is checked before the message is queued, so a file that WhatsApp would refuse comes back at you rather than failing silently later.
Interactive buttons
Reply buttons and link buttons, with media in the header — an image, a video or a document sitting above the text. This is where WhatsApp is more generous than Instagram, where a button can only carry an image.
Files up to 100 MB
Images, video, documents and audio. A PDF price list, a receipt, a catalogue — sent as the file itself, not as a link to somewhere else.
Audio, with one caveat
A voice note sends fine on its own. Attached to a message that also has buttons, WhatsApp returns a 400 and refuses it — so we send it as its own message rather than quietly downgrading your file to make the error go away.
Approved templates
Pre-approved messages, and the only way to start a conversation after the 24-hour window has closed. You manage them from inside Ignix rather than from Meta’s own console.
WhatsApp Flows
Forms that open inside the chat — a booking, a qualifying question, an address — so the person never leaves WhatsApp to fill something in.
The 24-hour window, and why WhatsApp is the exception
Every messaging network Meta owns has the same rule: a business may reply freely for 24 hours after the customer’s last message. After that, silence. It exists to stop businesses messaging people who have stopped talking to them, and it is a good rule.
On Instagram and Messenger that is genuinely the end. Ignix will tell you the window is closed rather than queue a message that cannot be delivered — which is more useful than a tool that accepts it and reports a failure the next morning.
On WhatsApp there is a door: a template message, approved by Meta before you ever use it, can open a new conversation. That is why WhatsApp is the channel worth building a longer sequence on. A reminder a week later, a delivery update, a renewal notice — none of those are possible on the other two, and all of them are ordinary here.
The bot answers, and then it knows when to stop
The AI agent learns your business from your own documents, your website and the answers you have already written, and replies in your voice rather than from a script someone else wrote. That part is the same agent that works your Instagram DMs and your website chat — one thing to teach, not three.
What matters more on WhatsApp is the handover. WhatsApp conversations get personal and specific faster than social DMs do, and the failure people actually remember is a bot that kept talking when it should have fetched someone. When the agent hits something it should not answer, the conversation is flagged for a human and the AI goes quiet on that thread until a person marks it handled.
It works the other way too: the moment an operator replies by hand, the AI stops on that conversation on its own. Nobody has to remember to mute it.
The same builder as everything else
A WhatsApp bot here is not a separate product with its own editor. It is the same visual flow builder that runs your Instagram comment-to-DM automations, pointed at a different channel — with conditions, delays, tags, custom fields and A/B branches, and with the nodes WhatsApp does not support simply not offered.
That last part is deliberate. WhatsApp has no comments, so there is no comment trigger and no comment-to-DM node. Rather than showing you a node that would fail at run time, the builder does not offer it on that channel at all.
Broadcasts and sequences work here too, and WhatsApp is the channel where they are worth the most — because it is the one where the template can reach someone whose window has closed.
On the official Business API
This runs on the WhatsApp Business API, the documented one. There is no phone in a drawer scanning a QR code, no unofficial library, and no account of yours quietly at risk of being banned for automating a personal number.
The practical consequence is that your business profile, your templates and your number live where Meta expects them to live, and the automation is something WhatsApp knows about rather than something it might notice.
Questions people ask
Is this a WhatsApp chatbot or a broadcast tool?
Both, and they share one contact list. The chatbot answers what comes in — keyword flows, buttons, an AI agent that replies from your own material. Broadcasts and sequences go the other way, out to people who have opted in, using approved templates so they land even when the 24-hour window has closed.
What happens 24 hours after someone messages me?
The free-form window closes and Meta stops accepting ordinary messages to that person. On WhatsApp you can still reach them with a template you had approved in advance; on Instagram and Messenger you cannot reach them at all until they write again. Ignix tells you which of the two you are in rather than queueing something that will bounce.
Can the bot send a PDF or a catalogue?
Yes — documents, images and video up to 100 MB, sent as the file rather than as a link. It can also sit as the header of a message that has buttons, so a price list and a “book a call” button arrive as one thing.
Do I need a separate phone number?
You need a number that is registered to the WhatsApp Business API, and it cannot be one already in use on the normal WhatsApp app on someone’s phone. Most businesses use a second number for this, which is also the honest answer to “can I automate my personal WhatsApp” — you should not, and this does not.
Can a person take over from the bot mid-conversation?
Yes, and it happens automatically: as soon as someone on your team replies by hand, the AI stops on that conversation. It stays quiet until the thread is marked as handled, so nobody has to remember to switch it off first.
Build the WhatsApp bot, keep the rest of the tool
WhatsApp is one of fourteen connected networks here, not a product you buy separately. The same flows, the same inbox, the same AI agent — and the calendar and analytics for everything you publish alongside it.
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