Send messages
Send your first WhatsApp message using the API.
Set up webhooks
Receive events in real time and integrate with your systems.
For AI agents
llms.txt
An index of the whole documentation in the llmstxt.org format. Paste it as the initial context in Claude Code, Codex, or OpenClaw and the agent gets oriented without browsing page by page.
Zapster CLI
npm i -g @zapsterapi/cli installs a wrapper over the REST API tuned for shells and agents. It ships a copy-paste quickstart so the agent can install and configure itself.Concepts
What is an instance?
Learn the concepts and terminology behind instances.
What are webhooks?
Concepts and terminology behind webhooks.
Access tokens
Understand what they are and how they work.
Rate limit
The 3 req/s limit, the
RateLimit-* headers, the 429, and how to handle it.