Zernio WhatsApp API - One API for WhatsApp: messaging, calling, and AI agents
You knew Zernio as the API for social media. Now it does WhatsApp too, the whole thing.
Connect a number and you've got the entire WhatsApp Business API behind it: messaging and broadcasts, in-chat forms, calls you can route to AI agents, chatbots, group chats, and numbers in 53 countries. Whatever you need to build on WhatsApp, it's one integration.
Made for developers and the agents they build: REST, SDKs, CLI, and a hosted MCP server.
Official WhatsApp Business API. Zero markup on usage.
Replies
Cutsio
Is any meta account linking required for these WhatsApp numbers? AFAIK, meta is really aggressive with marking things spam and with recent mass Instagram accounts banning fiasco, more so
Zernio
@rish404 Great question Rish! Yes, Meta Business account is required - you go through Meta's Embedded Signup to connect your WABA. But Zernio makes it quick: you can get a new number provisioned through Zernio or bring your own.
On the spam concern: since it's the official WhatsApp Business API, Meta's own quality controls apply. no risk!
I love Zernio! I'm really happy I've discovered it a few months ago which saved me tons of hours of Metas awful APIs. Zernio is now the backbone of my own app. Great work guys!
Zernio
@oliversch21 Really appreciate this feedback, Oliver! We will keep up the work 💪🏻
Zernio
@oliversch21 thank you, means a lot to us!
Zernio
This is an insane product and an amazing team effort! Let keep pushing!
Zernio
After seeing from the inside how the team built this WhatsApp integration, it was just amazing. I'm so excited for you all to enjoy it and try it! ❤️
This is really cool! Having messaging, calls, and AI agents all through one WhatsApp API is a huge deal for developers. Quick question — does it support sending media files like images or PDFs in messages, or is it mainly text-based for now?
Zernio
@doganakbulut thank you! Full media support, not just text. You can send images, videos, documents, and audio (incl. native WhatsApp voice message format)
Zernio
@lakshminath_dondeti thank you! For rate limits I think our docs provide a good picture on that - https://docs.zernio.com/guides/rate-limits#api-request-limits
and regarding the "who viewed your profile": not available, as there is no official LinkedIn API endpoint that allows developers to extract or see who viewed your profile
Blazly Backlinker
Hey Zernio team! 👋
Congratulations on the launch! 🎉
I love the idea of a unified social API. Handling multiple APIs and auth flows is a pain, so one layer for publishing, inbox, analytics, and account management is super valuable.
We're also launching Blazly Backlinker today, helping marketers automate backlink discovery, outreach, and guest posting from one workflow.
Would love to hear your thoughts if you get a chance to check us out as well. Best of luck with the launch! 🚀
The calling + AI agents combo in a single API is what makes this stand out - most WhatsApp integrations I've looked at just cover messaging. Been thinking about building something that handles voice callbacks automatically and the current options are painful. Question for the team: how does the rate limiting work when you're running outbound AI agent campaigns at scale? That's usually where these tools hit unexpected ceilings.
Zernio
@galdayan great question! Rate limits come from Meta's tier system, not Zernio. You start at 250 unique contacts/day (if you're a new account) and scale up automatically based on volume and quality history, with no hard cap once you're in higher tiers.
For calling specifically: outbound requires your number to be at the 2,000/day messaging tier. Also worth knowing that outbound calls are blocked by Meta for US, Canada, and a few other markets (inbound still works). So for voice callback campaigns at scale, a non-US number is the way to go. While the AI agent side is connected to Zernio separately and its rate depends on the provider you use.
Indie.Deals
The channel line up is crazy @dasha_nazarova1
Does this mean through Zernio, there could also be 2-way AI-assisted Whatsapp conversation also possible?
And we all know how tricky it is to get things done through Meta, would Zernio assist in the process in case there are issues connecting and setting up Meta + WhatsApp?
Excited to explore this further during the weekend.
Zernio
@adithya yes, fully supported. Zernio's Inbox API gives you incoming messages via webhooks (message.received) and lets you reply programmatically. So you can build an AI agent that receives a WhatsApp message, processes it, and replies, all via API
WhatsApp is such an important channel for SMB workflows because it mixes support, sales, reminders, and relationship management in one place. The MCP angle is interesting. How do you think about guardrails for AI agents using WhatsApp: template approvals, human handoff, and preventing an agent from over-messaging a customer?
Zernio
@rahulbhavsar great question! A few guardrails are built in by default: template approvals required outside the 24h window (Meta's own anti-spam layer), and a native Handoff node to transfer to a human at any point. Over-messaging is harder to solve at infra level, but the builders using Zernio tend to care about this. Nobody building a serious product wants to spam their customers.
That makes sense. Meta’s template approval plus a native human handoff already covers two of the biggest risk areas: consent/compliance and escalation.
I agree over-messaging is harder because it is partly a product and operator problem, not just infrastructure. One useful layer might be campaign-level limits or intent-based throttling, so teams can define when automation should slow down even if the API technically allows another message. That kind of guardrail would make WhatsApp automation feel much more trustworthy for serious B2B use cases.