WhatsApp chatbot: official API or a connected phone (and why it matters)
There are two technical ways to put a bot to work on WhatsApp, and they cost you very different things. From the outside they look alike: a number, a chat, automatic replies. Underneath they have nothing in common, and the difference only shows once you have paid, once the volume climbs, or the Tuesday morning your number stops working. This explains both routes, what breaks in each one, and what to ask before you sign.
The two routes, briefly
The official route runs on Meta's WhatsApp Business API. There is a registration in your business's name, with verification along the way, and conversations travel over Meta's infrastructure with its permission. It is the route Zepai takes, and Zepai is an Official Meta Partner. The exact requirements are Meta's and Meta changes them when it wants, so you check them when the project starts. That is the deal: you accept rules and paperwork, and in return you get a recognised channel for handling a lot of people.
The other route hooks up a phone, or an emulator pretending to be one, to a program that reads and writes for you. It is usually sold as needing nothing from Meta, no permissions and no verification, and it goes up fast. What nobody mentions is that there is no agreement with the platform behind it: the program behaves like a person holding a phone, on an ordinary user account, which is not what Meta offers businesses for handling customers. Everything that follows comes from that single detail.
What breaks when the bot runs through a phone
The first risk is the number itself. A user account is not built to be run by a program, and nobody outside Meta knows what the detection looks at. The decision is the platform's, and you find out afterwards. If the number goes down, you appeal as a private user, not as a registered business, and you control neither the timing nor the outcome. And the number that gets blocked is not a minor asset: it is the one printed on your signage, your invoices and every ad you have paid for.
The second is concurrency. A user account is one person's account, built for that person to handle their own conversations. A support channel with many messages at once is a different problem, and the setup layered on top does not always hold. You can end up with queues, late replies or crossed conversations. In a quiet business none of that shows. It shows on the good day, the promotion day or the bank holiday, which is the worst possible day for it to show.
The third is that you do not know whether the message arrived. The official route is an integration: your system asks Meta's to send and gets an answer back, so there is a trace. On the other one, you have an assumption. If a message does not arrive, you find out when the customer complains, or you never find out at all. For a marketing blast that may not matter. For confirming a booking or sending an appointment reminder, it matters a lot.
Meta sets the rules of the channel
On the official route you do not write whenever you feel like it. Meta separates the conversation the customer opens from the one you open: when somebody writes to you there is a window in which you can reply normally, and outside that window restarting contact stops being free-form. That is where templates come in: messages written in advance that have to go through approval before you use them. The timings and the requirements are Meta's and have changed over time, so you check them when you build. The logic is clear enough: to stop the channel filling up with companies writing to people who never asked.
That rule changes how the bot is designed. An appointment reminder, an order confirmation or a note that a slot has opened up tomorrow are not improvised: they are written and approved beforehand, not on the day the idea occurs to you. It also changes how you think about alerts: writing first becomes a decision. Whoever builds the unofficial version works with none of this, and that is the fragile part: where there are no rules to follow, there is nothing backing you either.
Which number you register
This one is worth understanding upfront rather than afterwards. A number registered on the API stops being used the way it was: the conversation moves into the tool connected to the API, and that is where your team replies when a human is needed. Do not assume you will have it on the bot and on the manager's phone at the same time. Ask what happens to that number and what it would take to undo it, because undoing it is work too.
The practical consequence is that you have to choose which number gets registered. If the phone the owner carries in his pocket is the one that appears everywhere, registering it means changing how the whole team works. Sometimes it is worth it and sometimes it is not, which is why the normal thing is to discuss it before touching anything: a new number for the automated channel, the usual one for whatever stays human. It is a short conversation, and it belongs at the start.
What the official route takes away from you
The official route is slower to start and more rigid. You have to verify the company, wait for approvals, write the templates carefully and expect that some will not pass first time. It is no use for cold-messaging a purchased list, and for anyone who wanted exactly that, it is a no. If your plan was mass messaging people who never gave you their number, neither route works for you; with the other one you are also risking the number.
And there is a more awkward case: you may not need a bot at all. If you get few messages a day and you answer them well, automating adds a layer to maintain without taking work off your plate. Sometimes the answer is not to automate, or to automate only the boring part, the opening hours and the address, and leave whatever actually closes a sale to a person. We would rather say that on the first call than charge for it and watch you switch it off.
How to spot the fragile version being sold to you
Some of the signs show up in the quote itself. Nobody asks you to verify the company or to get access to a business manager. You are told you can keep using your usual number, exactly as it is, on the phone and on the bot at the same time. The word template never appears, nor a single line about the rules Meta sets for what you are about to build. Nor a business account in your name, because that setup does not need one.
Another sign is what happens when you ask about failure. Ask what happens if the number gets blocked, and listen to the answer. If it is «we will swap it for another one», you now know that changing numbers is part of the plan, and that means changing what you have advertised everywhere. Ask, too, whose name whatever gets registered is under, and where the history sits if you part ways tomorrow. That is your customers' data: who holds it, and under what agreement, has to be in writing.
What to ask whoever quotes you
Four questions help tell a serious quote from a fragile one. First: does this run on the official WhatsApp Business API, yes or no? Second: whose name is the business account under, mine or yours? Third: which templates are we registering, and who writes them? Fourth: what happens when somebody replies on Monday to something from Friday, with the conversation already closed? Anyone working on the official route has those answered already: they are the decisions you have to make to build it. If instead they explain why the questions do not matter, that is an answer too.
At Zepai we build WhatsApp chatbots on the official API, and we are an Official Meta Partner. Most projects go live in five to seven working days, and we reply in under twenty-four hours. The price depends on the channels, the volume and what has to be integrated, so it is something to talk through. When we finish, we train you so you can change wording and flows without calling us. Write to info@zepaiagency.com or call +34 604 14 09 97.
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