Yeastar P-Series had collected a lot of messaging channels by autumn 2025: WhatsApp, SMS, Facebook Messenger and website Live Chat, all handled in Linkus. What was missing was a way for other software to join in. Yeastar's P-Series Cloud Edition 84.20.0.128, released on 13 October 2025, adds it: a full omnichannel Messaging API.
What's new in Yeastar 84.20.0.128
According to Yeastar's release notes, the new feature is the Omnichannel Messaging API, with:
- Four groups of API calls — message channels, message queues, message sessions and messages.
- Two new events — New Message Notification and Message Sending Result.
- Inbound routing to a third-party message analytics platform, such as an external bot.
- Session transfer from an agent to that platform (Linkus Mobile from version 5.19.7).
Improvements in the same release include:
- Microsoft Teams presence no longer overrides an extension's status while it's ringing or on a call.
- SIP authentication cache for register trunks.
- Separate visibility for internal and external chat in Linkus.
- Call Flow Designer: up to 10 variables in text-to-speech prompts, and a prompt-generation timeout.
- Neural voices for AI text-to-speech.
- Allowed Country IPs now lets trunk domain names through automatically.
- Send a call straight to voicemail from the incoming-call pop-up in Linkus Web, and a temporary status with an end time.
What the Messaging API covers
The API mirrors how messaging works in the PBX:
| Area | What you can do |
|---|---|
| Message channels | List, search and view channels; add, edit or delete them; get the Live Chat embed code; upload agent avatars |
| Message queues | List, search and view queues; add, edit or delete them |
| Message sessions | List, search and view sessions; transfer, close, archive, unarchive or delete them |
| Messages | Read the messages in a session; send messages or start a new session |
Together with the two new events, an outside system can follow every conversation as it happens and act on it.
Routing messages to a chatbot
The most practical use is automation in front of your team. Inbound messages from any channel can be passed through the API to a third-party platform — Yeastar's example is an external bot — for automated analysis and response.
A typical setup:
- A customer writes on WhatsApp or the website chat.
- The bot answers the simple questions: opening hours, order status, a link to a form.
- When it can't help, the conversation goes to a human in a message queue.
Agents can also go the other way and transfer a session to the platform from Linkus.
Before you build
- Pick one channel to start with — usually the busiest one — and add others once the flow works.
- Decide the hand-off rule up front: when exactly does the bot pass a conversation to a person?
- Use the events, not polling. The New Message Notification and Message Sending Result events tell your platform what happened as it happens.
- Test with real messages from a colleague's phone before you switch it on for customers.
Who should care
- Companies with a developer or an integration partner who want messaging in their own tools.
- Teams already using a chatbot or helpdesk who want it connected to the same channels their phones use.
- IT partners who build solutions for several customers.
If nobody on your side writes code, the API on its own won't change your day. Yeastar's later Message Flow Designer (V25.3, October 2026) offers drag-and-drop chatbots and auto-responders without programming — see our post on Message Flow Designer.
Which plan does it need?
Yeastar's release notes state that the Messaging API needs the Enterprise or Ultimate plan, with the API feature enabled. PBXfactory sells Yeastar P-Series Cloud on the Enterprise plan.
Some uses can depend on more than the plan — for example, the platform you connect may have its own costs, and some Yeastar features need the Ultimate plan or a paid add-on. If you have a specific integration in mind, ask our support whether it's available for your PBX before you build it.
On PBXfactory
On a Yeastar P-Series Cloud PBX from PBXfactory, Yeastar's firmware and security updates are applied for you — routine ones in announced maintenance windows, urgent fixes sooner.
Building an integration on the Messaging API is development work, and configuring channels and queues is PBX configuration — neither is part of included support. Yeastar's API documentation is thorough; your IT partner, a developer, or our paid support packages can take it from there. And if you're an IT partner building on Yeastar for your clients, have a look at our partner programme.