Zavu

Zavu provides a unified messaging API for developers and AI agents, covering WhatsApp, SMS, voice, email, Telegram, Messenger and phone numbers through one integration, one webhook and one bill. It also offers a runtime for building AI and voice agents as TypeScript code, plus SDKs, a CLI and an MCP server.

What It Is

Zavu is communication infrastructure for sending and receiving messages across channels. A developer logs in with the CLI or gets an API key, sends a message with a single call, and receives status changes on a webhook. With the channel left on auto, Zavu picks the route, using WhatsApp with SMS as the fallback.

The platform also covers buying phone numbers by API, WhatsApp templates, email from your own domain with DNS setup by API, broadcasts to contact lists, a shared inbox with contacts, and a project per client with its own key for agencies and platforms.

Agents and Functions

Agents are defined in TypeScript with defineAgent and defineTool and deployed with one command. They can run non-deterministically, where the model decides each reply, or deterministically with defineWorkflow, where Zavu follows written steps including waits of hours or days. Agents can use a per-agent knowledge base, per-contact memory, and tools that call your own HTTPS endpoint or a handler in the same file. Models from OpenAI, Anthropic, Google or Mistral can be used with your own key, or through Zavu's managed gateway. A dry-run test delivers nothing, and live executions log tokens, latency, cost and tool calls. Voice agents use the same primitives, answer calls, and can transfer to a person and leave a transcript.

Agent-First Setup

Zavu says everything can be built by an agent. A setup prompt installs Zavu skills for coding agents such as Claude Code, Cursor and Codex, signs into the CLI and adds the MCP server. The MCP server exposes endpoints as tools, and the dashboard assistant can create senders, buy numbers and deploy functions step by step.

Developer Tooling

SDKs are available for TypeScript, Python, Ruby, Go and PHP, generated from an OpenAPI spec. Integrations listed include Vercel, Supabase, n8n, WordPress and GitHub deploys for functions.