The finding that surprises people
Channel choice affects adoption more than model choice does. A capable agent behind its own login gets abandoned; a modest agent inside the tool people already have open all day gets used daily.
Where you deploy determines whether the thing gets used. Here is a comparison of the realistic options and what each constrains.
The channels compared
| Slack | Teams | Web chat | ||
|---|---|---|---|---|
| Audience | Internal | Internal | Customers | Customers |
| Threading | Excellent | Good | None | Depends on build |
| Rich formatting | Good | Good | Very limited | Full control |
| Interactive buttons | Yes | Yes | Limited | Yes |
| Identity for permissions | Built in | Built in | Phone number only | Your auth |
| Message cost | None | None | Per conversation | None |
| Approval required | App review | App review | Meta business verification | None |
The identity row matters more than it looks. Slack and Teams give you a verified organisational identity, which makes per-user permission mapping straightforward — the agent can act with that person's access rights. WhatsApp gives you a phone number, which is a weak identity signal for anything sensitive.
Internal agents: Slack or Teams
Choose by where your organisation already lives. Practical notes for either:
- Use threads. A long agent response in a busy channel is noise; in a thread it is helpful.
- Respond in the thread the question was asked in, preserving context.
- Use interactive elements for approvals — a button is far better than asking someone to type "yes".
- Show sources as links, so people can verify without leaving the conversation.
- Handle the ephemeral versus public choice — some answers should only be visible to the asker.
- Respect channel context — an agent in a customer channel should behave differently to one in an engineering channel.
The single most effective internal deployment pattern: an agent that answers when mentioned in any channel, in a thread, citing its sources. No new tool to learn, no context switch, and the answer is visible to everyone in that channel — which multiplies its value beyond the person who asked.
Customer agents: WhatsApp in India and beyond
For consumer-facing use in India, WhatsApp is frequently the highest-engagement channel available. The constraints are specific:
- The 24-hour service window — free-form replies only within 24 hours of a customer message. Outside it, only pre-approved templates.
- Per-conversation cost, not per message.
- Business verification required, plus a dedicated number.
- Minimal formatting — no tables, no rich cards. Answers must be plain and short.
- Quality rating — poor recipient response degrades your number's standing.
Design WhatsApp answers for a small screen in a plain-text medium. An agent that produces well-structured markdown will send walls of asterisks that read as broken.
Web chat: full control, harder acquisition
- Complete formatting control — rich responses, custom components, inline forms.
- Your authentication, so permission mapping is straightforward.
- No per-message cost.
- But: users must be on your site, and a widget competes with everything else on the page.
Best for pre-sales questions from people already evaluating you, and for authenticated customer portals where the agent has real account context.
Architecture: one agent, many adapters
- Build the agent as a service with a clean API — reasoning, retrieval and tools live here.
- Write thin channel adapters handling formatting, identity resolution and channel-specific interaction.
- Normalise identity at the adapter layer, so the core agent always knows who it is acting for.
- Adapt response formatting per channel — same content, appropriate presentation.
- Log centrally with the channel recorded, so you can compare usage patterns.
Permission mapping must happen per channel. A Slack user identity maps to your internal permissions cleanly. A WhatsApp phone number does not — which means customer-facing agents should be scoped far more narrowly, exposing only what is safe for a weakly-authenticated party to see.
Choosing for your case
| Your goal | Channel |
|---|---|
| Internal knowledge lookup | Slack or Teams |
| Support agent assistance | Inside your helpdesk, or Slack |
| Customer support, India/Asia | |
| Pre-sales questions | Web chat |
| Authenticated customer self-service | Web chat in your portal |
| Field or mobile staff | WhatsApp or a mobile app |
Planning where to deploy an agent? Tell us who the users are and where they work — that usually settles it. See our AI agent service, WhatsApp Business API guide, and internal knowledge bases.