Authenticate using a Sunshine Conversations API key ID and secret encoded as Basic Auth against https://api.smooch.io/v2
GET /v2/apps/{appId}/integrations to confirm which channels (whatsapp, messenger, web) are connected and retrieve their integrationId values
POST /v2/apps/{appId}/conversations/{conversationId}/messages with author.type=business, content.type=text (or structured carousel/buttons), and the message body to send an outbound message to the customer across any connected channel
Register a webhook via POST /v2/apps/{appId}/webhooks with a triggers array including conversation:message for inbound messages and an HTTPS target URL
Parse incoming webhook payloads — each event includes the appUser object, the channel source (integration type), and the message content
POST a reply message to the same conversationId to respond; use channel-specific content types (e.g., WhatsApp template message objects) when the channel requires it
Known gotchas
Sunshine Conversations API is accessed at api.smooch.io, not api.zendesk.com — mixing up the base URL returns auth errors that can be misdiagnosed as credential problems
The platform normalizes message content across channels but not every content type is supported on every channel — a rich carousel message will be downgraded or rejected on WhatsApp, which requires pre-approved templates for proactive messages
A standalone Sunshine Conversations subscription (beyond what is bundled with Suite plans) is required to access the full API and higher message volumes; Suite-bundled access has rate and feature limitations that are not always clearly documented
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp