# Documentation

Source: https://vertexsms.com/en/docs

Two ways to integrate with VertexSMS — pick the one that fits your workload.

- [Read the REST API documentation](https://vertexsms.com/en/api/introduction)
- [Read the MCP server documentation](https://vertexsms.com/en/mcp/introduction)

## REST API

The VertexSMS REST API for server-to-server integrations: send SMS and Viber messages, run HLR lookups, register Sender IDs, and read rates and operator metadata. Authenticate with an API token; standard JSON over HTTPS.

Best when your application calls VertexSMS from server code on a fixed schedule or in response to your own events.

[Read the REST API docs](https://vertexsms.com/en/api/introduction) — full reference also available as [api/llms.txt](https://vertexsms.com/api/llms.txt) (index) and [api/llms-full.txt](https://vertexsms.com/api/llms-full.txt) (full body).

## MCP server

The VertexSMS Model Context Protocol server lets AI assistants — Claude Desktop, Cursor, VS Code Copilot Chat, Claude.ai — use your VertexSMS account directly via tool calls. Bearer token or one-click OAuth 2.1 connect.

Best when an AI assistant needs to discover and use VertexSMS on demand without a hand-coded integration.

[Read the MCP server docs](https://vertexsms.com/en/mcp/introduction) — full reference also available as [mcp/llms.txt](https://vertexsms.com/mcp/llms.txt) (index) and [mcp/llms-full.txt](https://vertexsms.com/mcp/llms-full.txt) (full body).

## Not sure which to use?

If you are writing application code that calls VertexSMS programmatically, use the REST API. If you want an AI assistant — Claude, Cursor, or similar — to use VertexSMS for you, use the MCP server. The MCP server is a thin wrapper over the same REST API; it adds tool discovery and OAuth, and forwards every call to the API under the hood.

Account access is currently invite-only. [Contact us for access](https://vertexsms.com/en/contact).

## Site-wide indices

- [llms.txt](https://vertexsms.com/llms.txt) — full site map for LLMs
- [llms-full.txt](https://vertexsms.com/llms-full.txt) — full documentation body